10079-CV-LA-001-00 Tank Level Gauges (Revision 00) [PDF]

Zitiervorschau

WEIR LGE PROCESS

Weir LGE Process Project Number 10079

Hull numbers 2489, 2490 & 2501

Vendor Documentation, Tank Level Gauges

Document Number 10079-CV-LA-001-00

04 03 02 01 00

C. Ritchie

E. Heggie

B. Roeling

01 Dec 2011

First issue ** FOR INFORMATION ONLY **

Revision

Prepared

Checked

Approved

Date

Description

WEIR LGE PROCESS

Document Description

Document Number

Rev.

Issue Date

Drawing: wiring scheme (H235)

111020585_1

B

November 2011

Drawing: 821 indicator

111020585_2

A

March 2011

Drawing: 821 cut-out

111020585_3

A

March 2011

Drawing: dimensions PSU

111020585_4

A

March 2011

Drawing: 807 installation

111020585_4

A

March 2011

Drawing: dimensions 807

111020585_5

B

September 2011

Drawing: dimensions 807 float

111020585_6

B

November 2011

Drawing: electrical connection

111020585_7

A

March 2011

Drawing: H235 modbus

111020585_8

A

March 2011

Instruction manual: FTLG 807 marine level gauges

-

-

November 2009

Instruction manual: AMTG 821-02 remote level indicators

-

-

November 2009

Material list

EL-LA-001-00

-

-

8

7

6

5

4

3

2

1

FTLG 807 LEVEL GAUGES F

F

E

E

HAZARDOUS AREA

D

SAFE AREA

D POWER

+ -

+ -

POWER

POWER

C

C

RS232/485

BLUE MARKED AREA

BLUE MARKED AREA

To IAS (RS485)

Scale

B

12VDC OUT + + -

N=Quantity Level Gauges = 8 pcs

-

DC 12V 180W / 270W

1215V

Date Drawn 31-07-2006 Chckd. 08-08-2007 Appr. 15-11-2011 Final Dwg number

DC ok Overload

PULS

A

AC 100-240V

N

L

100 ~ 240VAC INPUT

8

7

6

B A

X- level gauges Changed layout

No.

Revisions

8/11/11 MRG 13/03/11 MRG Date

5

Cust. Ref. 10079-BB-LA-001

Name HAK MB SvdB MRG

B

Hull 2489

Title / Subject

Wiring Scheme (H235) By:

For:

4

P.O.

PO Box 198 3330 AD Zwijndrecht (NL) Tel +31 786100999 Fax +31 786103214

www.HSH.nl

111020585 _1

Name

Weir LGE

3

2

1 A4

Henri Systems Holland BV

1

A

8

7

6

5

4

3

2

1

144

137

F

F

96

89

E

E

BACK VIEW

FRONT VIEW CONSOLE FRONT (MAX 10 MM THICK)

158

D

MOUNTING BRACKET

D

PANEL CUT OUT = 138 x 90 mm

C

C

96

B

Scale

198

Cust. Ref. 10079-BB-LA-001

SIDE VIEW Date Drawn 31-07-2006 Chckd. 08-08-2007 Appr. 15-11-2011 Final Dwg number

A

8

7

Weir LGE

6

A

Changed layout

No.

Revisions

Name

Hull 2489

Title / Subject

2

821 Indicator By:

For:

4

B

PO Box 198 3330 AD Zwijndrecht (NL) Tel +31 786100999 Fax +31 786103214

www.HSH.nl

111020585_2

13/03/11 MRG Date

5

Name HAK MB SvdB MRG

P.O.

3

2

A4

Henri Systems Holland BV

1

A

8

7

6

5

4

3

2

1

138 F

F

90 E

E

Minimum 30

Minimum 20

D

D

C

C

Scale

B

Weir LGE

Cust. Ref. 10079-BB-LA-001 Date Drawn 31-07-2006 Chckd. 08-08-2007 Appr. 15-11-2011 Final Dwg number

A

8

7

6

A

Changed layout

No.

Revisions

5

Name

Hull 2489

Title / Subject

3

821 Cut-out By:

For:

4

B

PO Box 198 3330 AD Zwijndrecht (NL) Tel +31 786100999 Fax +31 786103214

www.HSH.nl

111020585 _3

13/03/11 MRG Date

Name HAK MB SvdB MRG

P.O.

3

2

A4

Henri Systems Holland BV

1

A

8

7

6

5

4

3

2

1

105

F

F + + -

DC 12V 180W / 270W

1215V DC ok

E

E

Overload

DIN rail mounting

PULS

125

D

D

AC 100-240V

N

C

L

C

60

110

Scale

B

Weir LGE

Cust. Ref. 10079-BB-LA-001 Date Drawn 31-07-2006 Chckd. 08-08-2007 Appr. 15-11-2011 Final Dwg number

A

8

7

6

A

Changed layout

No.

Revisions

5

Name

Hull 2489

Title / Subject

4

Dimensions PSU By:

For:

4

B

PO Box 198 3330 AD Zwijndrecht (NL) Tel +31 786100999 Fax +31 786103214

www.HSH.nl

111020585 _4

13/03/11 MRG Date

Name HAK MB SvdB MRG

P.O.

3

2

A4

Henri Systems Holland BV

1

A

8

7

6

5

4

3

2

1

F

F

E

E

D

D

C

C

Scale

B

Weir LGE

Cust. Ref. 10079-BB-LA-001 Date Drawn 31-07-2006 Chckd. 08-08-2007 Appr. 15-11-2011 Final Dwg number

A

8

7

6

A

Changed layout

No.

Revisions

5

Name

Hull 2489

Title / Subject

4

807 Installation By:

For:

4

B

PO Box 198 3330 AD Zwijndrecht (NL) Tel +31 786100999 Fax +31 786103214

www.HSH.nl

111020585 _4

13/03/11 MRG Date

Name HAK MB SvdB MRG

P.O.

3

2

A4

Henri Systems Holland BV

1

A

8

F

7

6

5

Holes BC D

4

3

2

1

F

JUNCTION BOX

FTLG 807 MARINE LEVEL GAUGE FLANGES (DN150 or 6") OIL FILL

D BC Holes DIN PN16 285 240 DIN PN40 300 250 ANSI 150LBS 11" 9 1 2" ANSI 300LBS 12 1 2" 10 5 8" JIS 10K 280 240 JIS 20K 305 260

380

E

3

4" 3 " 4

E

500 335

D

266

JUNCTION BOX

C

D

Lifting Eye

273 C

CABLE GLAND

482 FTLG 807 MARINE LEVEL GAUGE OIL DRAIN

345

Material: all Stainless Steel 316 (SUS) Measuring Drum & Wire: SUS 316 (Optional INVAR 36) Material Float: SUS 316L(Max operating pressure: 20 bar) Total weight: approx. 70 kg

HAND CRANK

FLOAT POSITION IN TOP

Scale

B

105

A

8

Cust. Ref. 10079-BB-LA-001

25

Date Drawn 31-07-2006 Chckd. 08-08-2007 Appr. 15-11-2011 Final Dwg number

45

FLOAT SUS 316

7

Weir LGE

6

B A

Multiple Flanges Changed layout

No.

Revisions

26/09/11 MRG 13/03/11 MRG Date

5

Name HAK MB SvdB MRG

Hull 2489

Title / Subject

5

Dimensions 807 By:

For:

4

B

PO Box 198 3330 AD Zwijndrecht (NL) Tel +31 786100999 Fax +31 786103214

www.HSH.nl

111020585 _5

Name

P.O.

3

2

A4

Henri Systems Holland BV

1

A

8

F

7

6

5

Float assembly Weight = 338 g Material = SUS 316L P/N = 0807.270

4

3

2

1

F

24 23 22 IMMERSION

21 20

E

E

19 18 17 16 15

D

D 425

475

450

500 DENSITY

525

575

550

600

C

C

SG = 0.45 45 21.7

SG = 1.00

Total volume: 500 cm3

10

Scale

B

Weir LGE

Cust. Ref. 10079-BB-LA-001 Date Drawn 31-07-2006 Chckd. 08-08-2007 Appr. 15-11-2011 Final Dwg number

A

8

7

6

B A

Immersion Changed layout

No.

Revisions

8/11/11 MRG 13/03/11 MRG Date

5

Name HAK MB SvdB MRG

Hull 2489

Title / Subject

6

Dimensions 807 Float By:

For:

4

B

PO Box 198 3330 AD Zwijndrecht (NL) Tel +31 786100999 Fax +31 786103214

www.HSH.nl

111020585 _6

Name

P.O.

3

2

A4

Henri Systems Holland BV

1

A

8

7

6

5

4

3

2

1

F

F

E

E

2 2.5mm

SCREEN

+ -

D

POWER

1

D

GROUND

2

C

C 6

7 1 2 3 5 4

12V FROM PSU

SAFE AREA

HAZARDOUS AREA Scale

B

Weir LGE

Cust. Ref. 10079-BB-LA-001 Date Drawn 31-07-2006 Chckd. 08-08-2007 Appr. 15-11-2011 Final Dwg number

A

8

7

6

A

Changed layout

No.

Revisions

5

Name

Hull 2489

Title / Subject

7

Electrical connection By:

For:

4

B

PO Box 198 3330 AD Zwijndrecht (NL) Tel +31 786100999 Fax +31 786103214

www.HSH.nl

111020585 _7

13/03/11 MRG Date

Name HAK MB SvdB MRG

P.O.

3

2

A4

Henri Systems Holland BV

1

A

8

7

6

5

4

3

2

1

J1

F

F +12V

0V

V1 V2

95

E

79

E

74 83.5 J2

H-Bus 235

Henri Systems Holland BV

SCAN

COM A

B gnd

D

D 25

J3

TOP VIEW

SIDE VIEW

C

C

Scale

B

Weir LGE

Cust. Ref. 10079-BB-LA-001 Date Drawn 31-07-2006 Chckd. 08-08-2007 Appr. 15-11-2011 Final Dwg number

A

8

7

6

A

Changed layout

No.

Revisions

Name

Hull 2489

Title / Subject

8

H235 Modbus By:

For:

4

B

PO Box 198 3330 AD Zwijndrecht (NL) Tel +31 786100999 Fax +31 786103214

www.HSH.nl

111020585 _8

13/03/11 MRG Date

5

Name HAK MB SvdB MRG

P.O.

3

2

A4

Henri Systems Holland BV

1

A

INSTRUCTION MANUAL FTLG 807 marine level gauges

Work address:

Mail address:

Henri Systems Holland B.V. Scheepmakersstraat 33 3334 KG Zwijndrecht Netherlands Tel: +31 (0)78 6100999 Fax: +31 (0)78 6103214

Henri Systems Holland B.V. P.O.Box 198 3330 AD Zwijndrecht Netherlands E-mail: [email protected] www.hsh.nl

Version: November 2009 (0911)

1

©Henri Systems Holland B.V.

The FTLG 807 marine level gauge for gas carriers 1. Introduction IMO resolution A.212 (VII) and resolution A.328 (IX) give the following definition for a "closed type" liquid level gauge: -"

Closed devices, which penetrate the cargo tank, but which form part of a closed system and keep the cargo (-tank contents) from being released, such as float type systems,-".

The HSH FTLG 807 series marine level gauge is a float type level gauge with a linear spring-motor to provide power for measuring liquid level in cargo tanks. The FTLG 807 series marine level gauge can be used on all types of ships carrying liquefied gases in bulk. The HSH marine level gauging system provides standard local digital level read-out, manual float hoisting and locking, automatic float descent control and further possibilities for centralized cargo handling with intrinsically safe level transmission and electronic digital read-out, integral level alarms and a variety of electronic signal outputs.

Version: November 2009 (0911)

3

©Henri Systems Holland B.V.

1.1 Level gauge construction and working principle The gauge head of the 807 series level gauge is made of two completely separated and closed compartments. The communication between both compartments is indirect by means of a magnetic coupling. One of the compartments, the so-called measuring drum compartment, communicates directly with the tank, and is thus part of the closed system. The measuring drum compartment houses an accurately machined measuring drum on which a flexible multi-stranded measuring cable is wound in a fine, screw-thread like groove. The float is fitted to the measuring cable and serves as level sensing element. The measuring drum is coupled through a magnetic coupling to the spring-motor, housed in the second compartment, the so-called spring-motor compartment. The spring-motor provides a constant torque via the magnetic coupling to the measuring drum in the rotation direction for winding-up the measuring cable. Under influence of the float weight a counter directed torque is applied from the measuring drum to the spring-motor via the magnetic coupling. The torque of the spring-motor is lower than the torque caused by float weight and measuring wire. The difference in torque allows the float to descent, but with the float at the cargo equilibrium will be reached as the float apparently obtains a lower weight in cargo. In this situation the spring-motor maintains a constant pull in the measuring cable. When the cargo level raises or lowers the float follows the level changes and causes the measuring drum to wind-up cable or to release cable. The rotation of the measuring drum and spring-motor is a measure for the amount of level change. To indicate the measured levels, a digital counter mechanism is fitted at the spring-motor to "translate" the measuring drum rotation in mm's level. The spring-motor basically consists of a storage drum, a torque output drum and a length of flat spring material. Each position of the flat spring material is preset to the same curvature in such a way that it can be completely straightened without deformation. Because of this presetting the spring material curls up and forms a coil. By mounting the coil on a free rotating storage drum and by uncoiling it reverse-bent on a torque output drum, a constant torque drive is constructed as the tendency of the spring material is to recoil to its preset curvature, thus imparting a constant torque to the shaft of the torque output drum. The 807 series marine level gauges are accurate level read-out instruments which are used during loading or discharging of tanks. During the voyage the floats must be hoisted to uppermost position. If, after loading, the cargo loading lines are blown empty, the floats must be hoisted first. Failure to do so may cause considerable damage to the instruments. The level gauge is provided with a float hoisting mechanism with magnetic slip-clutch that prevents over-winding. In uppermost position of the float the measuring drum is automatically locked. After unlocking of the measuring drum, the float descents with constant speed to the cargo surface or tank-bottom. The float descent speed is controlled by a regulator (paddle wheel) which rotates in the oil of the spring-motor compartment. This compartment is filled with approx.7 liters of oil. The oil serves not only the regulator, but also lubricates the spring-motor, provides a condense-free level display window and inhibits corrosion.

Version: November 2009 (0911)

4

©Henri Systems Holland B.V.

1.2 Level gauge identification code Position

:

1

2

3

4 56 7

Example

:

FTLG 8 0 7 SUS / TA 39

Pos. 1

:

FTLG = Float Type Level Gauge

Pos. 2

:

807, marine level gauge

Pos. 3

:

SUS = Stainless Steel (316) Measuring Drum and Measuring Wire INV = Invar 36 Measuring Drum and Measuring Wire

Pos. 4)

:

/ slash

Pos. 5)

:

T, with intrinsically safe level transmitter

Pos. 6)

:

A, with 2 integral level alarm switches

Pos. 7)

:

39, measuring range 0 – 39 m

Two compartment gauge housing

Version: November 2009 (0911)

5

©Henri Systems Holland B.V.

1.3 Accuracy The accuracy of the 807 series marine level gauges is determined by the following factors: a.

b.

c. d.

e.

f.

g. h.

The accuracy of the circumference of the measuring drum. The effective circumference of the measuring drum is 600 mm with a tolerance of ± 0.02 mm. The accuracy of the measuring cable diameter. The measuring cable is multi-stranded with a central core. The diameter has a max. tolerance of ± 0.02 mm. The weight of the suspended amount of measuring cable. The measuring cable has a weight of approx. 1.3 g/m. The hysteresis of the measuring system. The hysteresis is the total friction of bearings, regulation, indicator, etc. The parts housed inside the spring-motor compartment add very little to the hysteresis as they run under optimal conditions under oil, i.e. well lubricated, no corrosion influence. The measuring drum runs under more severe conditions which require a suitable approach. Depending on the type of tanker or application, measuring drum bearings will be selected for their typical operational conditions. Depending on the selection of the type of measuring drum bearings, the hysteresis may vary from a maximum allowable 40 g (measured at the measuring cable as top-top-value) to only 10 g. The accuracy of constant torque output of the spring-motor. The spring-motor has a linear character with a tolerance of ± 10 g (measured at the measuring cable). The density of the cargo influences the buoyancy of the float or the displacer. In light cargoes the float will sink deeper than in heavy cargoes. See float immersion diagram. The size and type of float used. Small diameter floats are more influenced by change of density than larger diameter floats. See also float immersion diagram. The cargo- and tank temperature can influence the accuracy of the measuring system, particularly if the tank material is different of that of the measuring cable and measuring drum. The difference in thermal expansion co-efficient of different materials causes measuring errors, but these may be partly compensated by way of mounting construction. The temperature compensation diagram indicates maximum possible measuring errors, caused by measuring wire expansion.

Considering only the factors a., b., c., d. and e. the accuracy of the measuring system can be expressed in the following formula: ∆ L = ± (2.0 + 0.15 l) mm (l is the amount of suspended measuring cable in meters). For factor d. the maximum allowable hysteresis has been used. For initial adjustment of the level gauge it is recommended to set the local indicator so, that the float or displacer is set for average immersion level (see float immersion diagram). Tankers carrying cryogenic cargoes (LNG etc.) may be fitted with level gauges with Invar (36% nickel steel) measuring drum and measuring cables.

Version: November 2009 (0911)

6

©Henri Systems Holland B.V.

2. Mounting 2.1 Mounting of level gauges, general The mounting flange of the HSH 807 series marine level gauge is compatible to: a. a 6" 150 lbs ASA r.f. flange b. a DN 150 PN 16 flange (DIN 2502) c. a 10K DN 150 JIS flange d. other flanges, such as 6” 300 Lbs, DN 150 PN 25/40 or JIS 20K DN150 are optional The display window of the local indicator should face aft, same as the hand-crank of the float hoisting mechanism. To have free access to the level gauge internals, for maintenance and calibration, it is recommended to have a free area with a radius of at least 1.5 to 2 meters around the level gauge. Trim or list of the ship has practically no influence on the accuracy of the level gauge.

2.2 Liquefied gas tankers According IMO resolution A.328 (IX) each cargo tank should be fitted with at least one liquid level gauging device. Where only one liquid level gauge is fitted, it should be arranged so, that "any necessary maintenance" can be carried out while the cargo tank is in service. For float-type liquid level gauges, "any necessary maintenance", includes inspection of the float and therefore it is recommended to mount the level gauge on a full bore ball valve or gate valve, which allows free passage of the float (see fig. 19). By using a float with a diameter of 125 mm the valve size can be generally limited to 6" ASA 150 lbs R.F. (or NW 150 ND 16). In most cases a perforated pipe will be required for float guiding. With a level gauge mounted above a ball- or gate valve it must be checked that the float is above the valve before closing the valve. Failure to do so will result in damage of float and/or measuring wire.

Typical gas tanker installation

Version: November 2009 (0911)

7

©Henri Systems Holland B.V.

3. Commissioning 3.1 Spring motor adjustment Next, check the correct operation and setting of the spring-motor. Release the float, applying a braking force to the spring-motor manually, all the way down until it reaches the tank bottom. Meanwhile, check that the torque output drum (fig. 5 item 46) rotates anti-clockwise (facing the spring-motor compartment) and the spring-storage drum rotates clockwise (fig. 5 item 45). If the float stops during its downward movement before it reaches the tank bottom, check that sufficient spring tape is left on the storage drum. If this is not the case, rotate the torque output drum (main shaft) 3 revolutions in clockwise direction by hand and lock the spring-motor by the engaging the float hoist mechanism. While rotating the torque output drum, check that the storage drum rotates anti-clock-wise (1800 mm on the local indicator). After the spring-motor has been locked, rotate the measuring drum in a clock-wise direction (facing the drum compartment) until the float reaches the tank bottom. Because the magnetic coupling of the measuring drum provides a counter force to the manually applied rotation force, it may be necessary to remove the drum from the shaft in order to prevent too high radial forces on the shaft. When the float has reached the tank bottom, dis-engage the float hoisting mechanism and check that the float is still resting on the bottom. Hoist the float and release it once again, adjusting the speed carefully by hand. The vertical speed should be almost constant.

3.2 Local level indicator setting To set the local level indicator, the float must be placed at a known level (tank-bottom, liquid level or valve top). Compare the known level with the actual read-out of the local level indicator (fig. 4 item 61). During initial installation it is obvious that the factory setting is not similar to the required setting. To obtain an accurate setting the fixing screw of the local indicator (fig. 4) must be unscrewed. Pull out the local indicator and set it (approx.) to the required setting and fit it back into its position, so that the drive gear and indicator gear are not yet engaged. Now make the final setting (setting accuracy 2.5 mm) and fix the local indicator home, making sure that the gears are correctly engaged. Fasten the local indicator by tightening the screw.

3.3 Reference switch and level alarm switch (if fitted) Level gauges with intrinsically safe level transmission and digital remote level readout can be fitted with 2 level alarm switches and a reference switch. The reference switch is required when a level transmitter is fitted. The reference switch gives the "start" signal for the remote level indicator and ensures, during operation of the level gauge, synchronization of the local read-out and the remote read-out. Reference switch and level alarm switches are designed for NC (normally closed) circuit. The level alarm switches are optional when level transmission is fitted and can be connected to several types of HSH AMTG series remote level indicators.

Version: November 2009 (0911)

8

©Henri Systems Holland B.V.

3.4 Switch operation The reference switch must always be set to open when the float reaches the highest point (against float stops, against the mounting flange or above the valve). This means that the switch is closed from the moment the float is released and the level gauges thus in operation. A high level alarm switch must be set to open when the cargo level has reached the required level. Under this level the switch must be closed. A low level alarm switch must be set to open when cargo level has reached the required level. Above this level the switch must be closed. (This is contrary to the high level or reference). The construction of reference switch, high- and low level alarm switches is identical: a magnetically actuated "reed" contact. The "reed" contact is fitted on a printed circuit board. The complete print board is fitted at the switch frame. A small magnet is fixed in the last digit wheel (at the 2 o’ clock position). During non-alarm condition the magnet must be positioned directly in front of the embedded "reed" contact. In this position the switch is closed (normal condition). At the required level setting the magnet turns away from the "reed" contact, thus opening the switch. Remark: The turning direction of the spring-motor for setting high level alarm and reference is clockwise. For low level alarm the turning direction is anti clockwise.

3.5 Switch setting Turn the spring-motor by hand until the local read-out shows the required level alarm setting (for level alarm switches) or until the float has reached the highest point (just about to touch the float stops or mounting flange or just above the valve). Hold the level gauge spring-motor at this level. Slack the fixing screw of the switch. Pull out the switch from its fixed position by turning it slightly to the left. (Bayonet fitting). Turn the driving (first) digit wheel so that the magnet in the last digit wheel is just on the point of turning away from the embedded "reed" contact. Turn the driving digit wheel always in the same direction as if it would be driven by the spring-motor: for reference and high level spring-motor clockwise; for low level springmotor anti clockwise. Fit the switch in place, making sure that the gears are correctly engaged. Tighten the fixing screw and check the setting. Turn the spring-motor so that the float moves up and down. For reference and high level the switch must be closed when the float is below the required level setting and open above this point. For low level the switch must be closed when the float is above the required level setting and open below this point. The maximum setting accuracy is ± 2.5 mm. When the setting is not yet correct, slack fixing screw and pull the switch so far out that the gears are just disengaged. Turn the driving digit wheel just as many gear teeth as is required (observe correct turning direction) and fix the switch again. Location of the switches inside the spring-motor compartment: Reference switch High level switch Low level switch Transmitter

-

approx. approx. approx. approx.

Version: November 2009 (0911)

11o'clock position 8 o'clock position 5 o'clock position 12 o'clock position.

9

©Henri Systems Holland B.V.

3.6 Level transmitter (if fitted) The intrinsically safe level transmitter is designed to provide HSH AMTG series remote level indicators with level information. The level transmitter consists of a gear driven rotor disc and three inductive proximity switches. The level transmitter does not require adjustments or setting. The synchronization between local read-out and remote read-out is arranged by the reference switch in the level gauge and reference program in the remote level indicator.

3.7 Oil filling First fit the spring-motor compartment cover (fig. 3 item 7), making sure that no tools or dirt remain in this compartment. Check that the oil drain plug is tightened (fig. 3 item 11) and fill the spring-motor compartment with oil up to the oil fill plug level (oil fill plug fig. 3 item 11). At this level the oil can be seen through the read-out window. Close the oil fill plug and fit the measuring drum cover. The level gauge is now ready for operation.

3.8 Starting-up The measuring drum and float are already fitted in the factory and after the adjustment of local indicator and, if fitted, the reference switch and the level alarm switches, the level gauge can be closed and the instrument is ready for operation.

Version: November 2009 (0911)

10

©Henri Systems Holland B.V.

3.9 Recommended oils for level gauges Maker

Viscosity Index

Pour Point

Viscosity @ 40°C (mm2/s)

Flash point

1

Shell Tellus oil T 15

159

- 45°C

14.0 cSt

154°C

2

Mobil DTE II

150

- 40°C

15.8 cSt

165°C

3

B.P. Energol SHF 22

173

- 54°C

21.3 cSt

165°C

4

Gulf Hydraulic oil A

140

- 54°C

15.8 cSt

160°C

5

Esso Univis HP 22

171

- 45°C

20.0 cSt

196°C

6

Fina Hydran HV 15

156

- 46°C

15.0 cSt

180°C

7

Elf Hydref 22

182

- 40°C

21.0 cSt

190°C

8

Total Equivis ZS 15

151

- 42°C

14.7 cSt

174°C

9

Castrol Hyspin AWH 15

151

- 51°C

14.8 cSt

165°C

10 Chevron LPS 15

153

- 51°C

15.0 cSt

160°C

11 Texaco Rando HD-Z

151

- 42°C

15.0 cSt

150°C

12 Idemitsu Daphne Super Hydro X 15

144

- 50°C

15.4 cSt

178°C

Other hydraulic oil types may be used when the following specifications are met : Viscosity index Pour point Viscosity @ 40°C Flash point Oil color

: ≥ 140°C : ≥ - 40°C : ≥ 14,0 cSt : ≥ 150°C : clear

Oil capacity per level gauge: approx. 7 L.

Version: November 2009 (0911)

11

©Henri Systems Holland B.V.

4. Operation 4.1 Operation with manual float hoisting mechanism The operation of the level gauge is very simple. To hoist the float, simply place the hand crank (see fig. 3 item 90) on the shaft at the spring motor compartment and rotate slowly clock-wise. The magnetic coupling of hand crank and hoisting mechanism prevents over-winding. When the float has reached the highest point (against float stops) the hand crank slips through the magnetic coupling. Check the local read-out level. At the highest point of the float the level gauge is automatically locked. After the float is hoisted the hand crank must be removed. To start measurement the float must be released from the hoisted position. Engage the hand crank and turn 1 (one) revolution anti clock-wise. Remove the hand crank when the float is released. Float release is visible at the local read-out. Check the oil level at regular intervals (e.g. every month). A too low oil level will result in an excessive float descend speed. Normally the oil level is visible through the local read-out window.

5. Maintenance The oil filling of the level gauge should be renewed preferably once every 5 years. Always use clean oil for filling. The minimum and maximum oil level can be checked by removing the oil fill plug. Minimum level is at the lower edge, maximum is at the upper edge of the fill pipe stud. Once every 5 years the terminal box should be checked for moisture. If silica gel sachets are present, either renew or regenerate these. The bearings of the level gauge should be checked, and if necessary renewed, every 5 years. At the same time check the measuring cable and float for corrosion. Warning 1:

Never remove a measuring drum before locking the spring-motor. Failure to do so will unwind the spring-motor and cause severe damage. The oil in the spring-motor compartment does not have to be drained in order to lock the spring-motor. Fit the measuring drum in exactly the same position as it was taken out, e.g. with the float at the same level. If this is done correctly, re-adjustment of the level gauge is not required.

Warning 2:

DO NOT OPEN WHEN AN EXPLOSIVE ATMOSPHERE IS PRESENT.

Version: November 2009 (0911)

12

©Henri Systems Holland B.V.

6. Trouble shooting Diagnosis

Failure a.

The level gauge runs irregular

1.

Dirty measuring drum bearing and/or magnet separation cap.

b.

The float does not descend after releasing

1.

4.

Dirty measuring drum bearing and/or magnet separation cap. Valve below level gauge closed. Local level indicator, reference switch or alarm switch not correctly fitted. Obstacles in travel range of float.

1. 2.

Measuring cable broken. Measuring cable off the measuring drum.

2. 3.

c.

Level gauge indicator suddenly shows erroneous reading

d.

Float cannot be hoisted

e.

Float returns to cargo level after being hoisted

1.

Hand crank not taken off.

f.

Float is difficult to hoist

1. 2.

Hand crank not correctly fitted at shaft. Weak magnets

g.

Float descends too fast after releasing

Check oil level in spring-motor comp.

h.

Local indicator shows “impossible” reading

Measuring cable broken.

i.

Obstacles in float travel range.

Float submerges in cargo or remains at tank bottom with cargo in the tank

Version: November 2009 (0911)

Leaking float.

13

©Henri Systems Holland B.V.

7. Parts list 807 series marine level gauges Pos.

Fig.

Description

1 1 1 1 1 2 2A 3 4 4A 5 6 7 8 9 9A 10 11 11A 12 13 14 15 16 18 19 20 21 22 23 24 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47

3/13 3/13 3/13 3/13 3/13 13 13 13 13 13 13 3~9 3 3 3 3 3 2/3 3 10/11 10 9 10 10 13/14 14 14 14 14 14 14 13/14 18 18 11 12 12 12 12 12 12 12 12 12 12 15 11 11 15 15 5 5 5

Measuring drum compartment Measuring drum compartment Measuring drum compartment Measuring drum compartment Measuring drum compartment Cover drum compartment Plug 5/8" O-ring drum compartment Bolts drum cover

Part No.

0807.010 0807.011 0807.012 0807.013 0807.014 0807.021 0807.02A 0807.030 0807.040 Sealing bolt drum cover 0807.041 Spring lock washer drum cover 0807.050 Spring motor compartment 0807.060 Cover motor compartment 0807.070 Gasket motor compartment 0807.082 Bolts motor compartment 0807.090 Sealing bolt motor compartment 0807.09A Spring lock washer motor comp. 0807.100 Oil fill, oil drain plug 0807.110 Gasket Oilplug 0807.11A Magnetic separation flange 0807.120 O-ring drum side 0807.130 O-ring motor side 0807.141 Bolts separation flange 0807.150 Spring lock washer sep.flange 0807.160 Measuring drum SUS 316 0807.180 Outer magnet measuring drum 0807.190 Housing bearings measuring drum0807.200 Ball bearings measuring drum 0807.210 Spacer measuring drum 0807.220 Bolts bearing housing 0807.230 Washers bearing housing 0807.240 Measuring wire SUS 316 0807.260 Float set complete 127x45mm 0807.270 Float spring 0807.301 Main shaft assembly 0807.290 Main shaft housing 0807.300 Ball bearings main shaft 0807.310 Inner magnet main shaft 0807.320 Ring main shaft 0807.330 Bolt main shaft 0807.340 Key main shaft 0807.350 Main shaft 0807.360 Set ring main shaft 0807.370 Set ring screw main shaft 0807.380 Ring main shaft 0807.390 Screw transmitter 0807.400 Bolt main shaft 0807.410 Spring washer main shaft 0807.420 Screw transmitter 0807.430 Bolt transmitter 0807.440 Spring motor storage drum 0807.450 Spring motor drum (main shaft) 0807.460 Bush spring motor 0807.470

Version: November 2009 (0911)

14

Remarks SS 316L (SUS)Flange DN150PN16 SS 316L (SUS)Flange 6”150 LBS ANSI SS 316L (SUS)Flange DN150PN25 SS 316L (SUS)Flange 6”300 LBS ANSI SS 316L (SUS)Flange DN150PN40 Stainless steel 316 (SUS) for drum compartment

Stainless steel 316 (SUS) Stainless steel 316 (SUS)

Stainless steel 316 (SUS)

Complete encapsulated (SUS) Stainless steel 316 (SUS)

Including float spring (28) Pre-tensioned

Complete encapsulated (SUS)

©Henri Systems Holland B.V.

Pos. Fig. 48 49 50 501 51 52 53 54 55 56 57 58 59 60 61 62 64 65 66 67 68 69 70 70 71 72 73 731 74 75 76 77 777 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 92 94 95 96 97

Description

Part No.

Remarks

5 5 15 15 7 7 7 15 7 7 7 7 15 7 4 4 8 8 8 4 4 17 6 6 4 5 15 15 15 5 5 5 5 5 5 5 6/17 17 17 17 17 17 17 17

Bolt spring motor 0807.480 Key spring motor 0807.490 Rotor house transmitter 0807.500 Transmitter housing 0807.501 Feed through wire 807 0807.510 O-ring Feed through 0807.520 Rail with terminals 0807.531 Transmitter shaft 0807.540 Cover Junction Box 0807.550 Gasket Junction Box 0807.560 Bolt Junction Box 0807.570 Washer Junction Box 0807.580 Ring Junction Box 0807.590 Cable gland 0807.600 Local indicator Innage 0807.611 Reference / alarm switch 0807.620 Window local indicator 0807.641 Gasket Window local indicator 0807.650 Window frame local indicator 0807.660 Bolt to fix indicator/ switch 0807.670 Bolt to fix transmitter 0807.680 O-ring hoist\lock mechanism 0807.691 Nut for hoist\lock mechanism 0807.700 Nut special hoist\lock mechanism 0807.701 Transmitter complete 0807.710 Flange for spring 0807.721 Pulse rotor transmitter 0807.730 Ball Bearing transmitter 0807.731 Connector with switches 0807.740 Bolt to fit motor spring end 0807.750 Screw to fit motor spring end 0807.760 Set ring assembly 0807.770 Oil brake complete 0807.777 Gear wheel main shaft 0807.780 Bolt main shaft 0807.790 Washer main shaft 0807.800 Float hoisting mechanism 0807.810 Float hoist mechanism base plate 0807.820 Bolt hoist\lock mechanism 0807.830 Gear frame hoist\lock mechanism0807.840 Carrier coupling hoist\lock mechanism 0807.850 Conical gear hoist\lock mechanism0807.860 Magnet hoist\lock mechanism 807.904 Positioning magnet hoist\lock 807.904 mechanism 17 Shaft hoist\lock mechanism 0807.890 2/3 Hand crank 0807.901 16 Contact print reference switch 0807.910 16 Screw reference switch 0807.920 16 Screw reference switch long 0807.921 9 Bolt to fix motor compartment 0807.940 11/12 O-ring on main shaft (absorber) 0807.950 Nameplate 807 0807.961 Nut to fix window 0807.970

Version: November 2009 (0911)

15

©Henri Systems Holland B.V.

7.1 Recommended spare parts for level gauges

Pos.

Fig.

Description

Qty.

3/13 8 14 21 26 27 45 61 62 64 65 69 71 90

3/13 3 9 14 18 15 5 4 4/16 4 8 17 4/15 3

O-ring drum compartment Gasket motor compartment O-ring motor side Ball bearings measuring drum Measuring wire Float set complete Spring motor storage drum Local indicator Innage Reference or alarm switch Window replacement set Gasket window local indicator O-ring hoist/ lock mechanism Transmitter complete Hand crank

2 pcs 2 pcs 1 pcs 2 pcs 2 pcs 1 pcs 1 pce 1 pce 2 pcs 1 pce 2 pcs 1 pcs 2 pcs 1 pcs

0807.030 0807.082 0807.141 0807.210 0807.260 0807.270 0807.450 0807.611 0807.620 807 window 0807.650 0807.691 0807.710 0807.901

7.2 How to order spare parts When ordering spare parts, always state type and serial number.

7.3 Tools No special tools are required. With the following tools the level gauges can be completely serviced: 1 set of Allen keys, metric, 1 Allen key 3 mm extra long (140 mm) 1 open/ring wrench 10 mm. 1 ring wrench 18-19 mm 1 screw driver no. 3 1 set Philips screw drivers. 1 Multimeter

Version: November 2009 (0911)

16

©Henri Systems Holland B.V.

8 Specifications Performance: Measuring range Accuracy* Repeatability ` Sensitivity* Max. working pressure Minimum cargo temperature Maximum cargo temperature Ambient temperature

: : : : : : : :

0 – 39 m ∆L = ± (2,0 + 0,15L) mm (L is the meas. Level) ± 2,0 mm ± 1,5 mm 2,0 MPa (20 bar) - 165 °C + 90 °C - 20 °C ~ + 60 °C

: : : : : : :

AISI / SUS 316 AISI / SUS 316 or INVAR 36 AISI / SUS 316 or Invar 36 AISI / SUS 316 (welded, no seals) Stainless steel encapsulated SmCo AISI / SUS 316 ± 65 kg

* = @ max. inclination of 22,50° Materials: Gauge head Measuring drum Measuring wire Magnet separation Coupling magnets Float Weight Electrical: Sensor output circuits (terminal 1-a and 4S, 2-b and 4S, 3-c and 4S)

in type protection intrinsic safety EEx ia IIB, only to be connected to remote level indicator model AMTG 821/02 or certified intrinsically safe circuits, with the following maximum values for each circuit:

Ui Ii Pi Ci Li Alarm output (terminal 5-R and 4S, 6-A1 and 4S, 7-A2 and 4S)

= = = = =

16 52 169 30 50

V Ma mW nF µH

in type protection intrinsic safety EEx ia IIB only to be connected to remote level indicator model AMTG 821/02 or certified intrinsically safe circuits, with the following maximum values for each circuit: Ui Ii Pi Ci Li

= = = = =

16 52 169 0 0

V Ma mW nF µH

The sensor output circuits and the alarm output circuits have one connection in common.

Version: November 2009 (0911)

17

©Henri Systems Holland B.V.

9 Drawings of FTLG 807 series marine level gauges

Fig Fig Fig Fig Fig Fig Fig Fig Fig Fig

1 2 3 4 5 6 7 8 9 10

: : : : : : : : : :

Dimensions of level gauge Lay out of main components Open view of spring motor compartment Local indicator, reference/alarm switches and transmitter View of spring motor parts View of hoisting mechanism View of junction box Window parts and location Fitting spring motor compartment Fitting separation plate

Fig Fig Fig Fig Fig Fig Fig Fig Fig Fig

11 12 13 14 15 16 17 18 19 20

: : : : : : : : : :

Fitting main shaft Main shaft parts Open view measuring drum compartment Measuring drum assembly Level transmitter Reference or alarm switch Float hoisting mechanism Float Float immersion diagram Mounting of level gauge on gas carriers

Fig Fig Fig Fig

21 22 23 25

: : : :

Thermal expansion measuring wire in SUS 316 Thermal expansion measuring wire in Invar 36 Kema Certificate Level transmission and internal wiring

Version: November 2009 (0911)

18

©Henri Systems Holland B.V.

Fig. 1 Version: November 2009 (0911)

19

©Henri Systems Holland B.V.

Fig. 2

Version: November 2009 (0911)

20

©Henri Systems Holland B.V.

Fig. 3

Version: November 2009 (0911)

21

©Henri Systems Holland B.V.

Fig. 4

Version: November 2009 (0911)

22

©Henri Systems Holland B.V.

Fig. 5

Version: November 2009 (0911)

23

©Henri Systems Holland B.V.

Fig. 6

Version: November 2009 (0911)

24

©Henri Systems Holland B.V.

Fig. 7

Version: November 2009 (0911)

25

©Henri Systems Holland B.V.

Fig. 8

Version: November 2009 (0911)

26

©Henri Systems Holland B.V.

Fig. 9

Version: November 2009 (0911)

27

©Henri Systems Holland B.V.

Fig. 10

Version: November 2009 (0911)

28

©Henri Systems Holland B.V.

Fig. 11

Version: November 2009 (0911)

29

©Henri Systems Holland B.V.

Fig. 12

Version: November 2009 (0911)

30

©Henri Systems Holland B.V.

Fig. 13

Version: November 2009 (0911)

31

©Henri Systems Holland B.V.

Fig. 14

Version: November 2009 (0911)

32

©Henri Systems Holland B.V.

Fig. 15

Version: November 2009 (0911)

33

©Henri Systems Holland B.V.

Fig. 16

Version: November 2009 (0911)

34

©Henri Systems Holland B.V.

Fig. 17

Version: November 2009 (0911)

35

©Henri Systems Holland B.V.

Fig. 18 Version: November 2009 (0911)

36

©Henri Systems Holland B.V.

Fig. 19

Version: November 2009 (0911)

37

©Henri Systems Holland B.V.

Fig. 20

Version: November 2009 (0911)

38

©Henri Systems Holland B.V.

Fig. 21 Version: November 2009 (0911)

39

©Henri Systems Holland B.V.

Fig. 22

Version: November 2009 (0911)

40

©Henri Systems Holland B.V.

Fig. 25

Version: November 2009 (0911)

44

©Henri Systems Holland B.V.

INSTRUCTION MANUAL Type AMTG 821-02 Remote level indicators for: HSH marine type level gauges

Work address:

Mail address:

Henri Systems Holland B.V. Scheepmakersstraat 33 3334 KG Zwijndrecht Netherlands

Henri Systems Holland B.V. P.O.Box 198 3330 AD Zwijndrecht Netherlands

Tel: +31 (0)78 6100999 Fax: +31 (0)78 6103214

E-mail: [email protected] www.hsh.nl

Version: November 2009 (0911)

45

©Henri Systems Holland B.V.

10 Introduction The HSH AMTG Series Remote Level Indicators are designed for centralized display of liquid levels in cargo tanks, measured with the HSH/Enraf 806 or the FTLG 807 series level gauges. Additionally, output signals are provided by means of plug-in type PCB's for communications with remote data acquisition systems and/or analog or digital indicators. The remote level indicators are designed for flush panel-mounting and can easily be incorporated in (cargo) control panels. As the indicators are fully solid state, no maintenance is required. The actual level is displayed by means of a digital seven segment LCD display. Depending on the connection of the transmission cable level can be displayed in "ullage" or "innage" mode in metric units with increments of 1 mm. “Innage” read out is most common (“zero” level at tank bottom). The measuring range is from 0 to 99.999 mm. The transmission circuit between level gauge and remote level indicator is certified intrinsically safe as well as fail-safe: it is continuously monitored and in case of a failure that would result in an erroneous level indication, the display is blanked and a failure condition is indicated by a LED on the front panel.

10.1 Construction (see figures 28 and 29) The HSH AMTG series digital remote level indicators consist of the following parts: a. the indicator housing b. the PCB assembly Ad a. The indicator housing is fitted with a connector board at the back-end and is made so that it can easily be mounted in rectangular cut-out in (cargo) control panels. The housing is made of aluminum and is provided with the necessary fittings. The connector board at the back-end is (or can be) provided with connectors for: 1. (J8) transmission circuit (blue - indicating intrinsically safe circuit) 2. (J7) power supply 3. (J2) level alarm outputs (if fitted) 4. (J3) 4..20 mA level output (if fitted) 5. (J4) spare connection 6. (J5) TTL signal level parallel data output (if fitted) Ad b. The PCB assembly consists of two common printed circuit boards, located at the top and the bottom in between which the optional circuits are plugged. At least one option board, the level indicator, is fitted in every system. The PCB assembly slides into the indicator housing and is secured with four screws at the front of the indicator. The indicator front incorporates the following functions and indications: 1. level display (seven segment LCD). 2. fault indication (red LED). 3. synchronization indication (green LED). The sync. signal indicates that the float is hoisted in or near top position. 4 accept switch (push button). The accept switch is used to acknowledge level alarms 5. high/low level alarm signals (red LED's).

Version: November 2009 (0911)

47

©Henri Systems Holland B.V.

10.2 Working principle transmission The transmitter in the level gauge is supplied from the remote level indicator and provides the remote indicator with three separate level transmission signals. These signals are DC level pulses generated by three inductive proximity switches in the level gauge, and are amplified and buffered in the remote indicator. The three conditioned logic signals are then fed into a programmable logic device which generates an UP or DOWN pulse on its outputs for every mm level change of the gauge float. A bi-directional digital counter memory is controlled by these UP and DOWN pulses and therefore the actual counter value is directly proportional to the liquid level in the cargo tank. Because level transmission is relative, a provision is made to load the counter memory with a pre-defined value in order to synchronize the remote read-out with the local gauge indicator. Synchronization is controlled by a reference switch, located in the level gauge. This switch is adjusted that its contacts open near the float top position. When the float is released the switch contacts close and the reference value is loaded into the counter memory. Subsequently the counter is updated according to the UP and DOWN pulses received from the pulse transmitters. The reference switch state can be monitored on the front panel of the remote indicator (SYNC LED illuminated when the switch is open). A second function of the decoder circuitry in the remote level indicator is to monitor the pulse signals for possible faults (proximity switch value, poor cable connections, short circuits, etc.). If such faults occur, a fail memory is set and the LCD display is blanked. A fault indicator on the front panel is illuminated indicating the fault situation. The fail memory can be reset by hoisting the float into top position so that the reference value is reloaded into the bi-directional counter memory. If the error is eliminated the remote level indicator will display the correct level once the float is released again.

10.3 Level alarms The HSH AMTG series remote level indicators can be fitted with up to four level alarm indications for high and/or low level alarms. The input required for the "hard contact" level alarm circuit is an N.C. (normally closed) contact. This can be provided with built-in level alarm switches in the level gauge or from other sources if an independent level sensor is required. The "hard contact" alarms can be wired as either low or high level alarms. Two adjustable high level alarms are furthermore provided on the alarm option board. Alarm levels are set by means of two separate jumper fields. The supply of the level alarm switch(es) is provided from the remote level indicator. The returning signal (open = alarm, closed = normal) is amplified in the remote indicator and sent to the alarm handling circuit which drives the alarm indicator LED's on the front panel and up to four alarm output relays. For every alarm, an SPDT potential-free contact is available on the back panel of the remote level indicator. The alarm handling circuit offers the possibility to process the alarm presentation to individual requirements:

1.

2.

Flashing visual presentation at the indicator front upon occurrence of a level alarm signal. The output relay is energized. After alarm acknowledgment with the push button at the indicator front the alarm LED changes from flashing into steady ON, and the output relay is de-energized. When the level alarm signal is removed the alarm LED extinguishes and the alarm is automatically reset for processing new alarms. Same as above, but the output relay is energized until the float has been hoisted into top position (reference switch activates alarm reset).

Version: November 2009 (0911)

48

©Henri Systems Holland B.V.

11 Communication output possibilities 11.1 Current loop output The HSH AMTG series remote level indicators can additionally be fitted with an analog current output option board which allows connection of remote indicating devices such as analog or digital indicators, data acquisition systems, etc. A 4..20 mA output is available at the back side of the indicator. This signal is generated by a 16-bit high precision D/A converter

11.2 Parallel data output If direct parallel input lines are available on the host computer system an optional parallel output can be fitted. The output port consists of a five bit wide address bus, enabling parallel connection of up to 15 remote level indicators on a single data bus. The data bus is 8 bit wide. 16 Bit data transfer is obtained by setting high or low the 5th address line resulting in data output of the high or low 8 bit data.

11.3 MODBUS H235 serial data output In case of interfacing requirements to central computer systems, PLC's or the like, where as little as possible intermediate calculations are to be performed by this computer system, an intelligent serial data output board can be fitted that can communicate using Modicon's MODBUS protocol. The H235 MODBUS interface provides access to the measurement- and status data of up to 16 remote level indicators through the 821.02 parallel interface boards. In situations where direct parallel interfacing is impossible or too complicated, application of the H235 interface may drastically reduce the amount of software- and hardware engineering. One of the great advantages of the MODBUS protocol is that it is supported standard in many available PLC and IAS systems. Integration in any automation system is therefore in most cases a matter of hours. A full description of the structure of this relatively simple master/slave protocol falls beyond the scope of this instruction manual; however, as the Internet provides a vast amount of information with respect to the command structure of the protocol that is freely available to the public it should not be too difficult to obtain all the information required to implement it into any particular automation system. It should be noted that the H235 only implements the most basic MODBUS functions and hence may put some restrictions on the infrastructure used. To prevent problems, we suggest to study the datasheet provided in the table on page 23 prior to designing the interface. Serial interface The H235 module is provided with two hardware-interfaces at the network side: either RS232 or RS485 can be used. In order to select the required interface type, it is necessary to set four jumpers into the correct position as indicated in figure 37. It is vital that the correct interface type is selected prior to connecting the interface to the network as incorrect strapping may damage either the interface of the driver stage of any other device connected to the same bus. The serial output port, both in RS232 and RS485, provides galvanic isolation from the remote level indicators and their power supply. It is essential that no connections are made between the serial port ground and power supply if separation is to be maintained.

Version: November 2009 (0911)

49

©Henri Systems Holland B.V.

RS232 interface The RS232 interface should only be used in situations where the distance from the H235 interface to the bus master is less than 12 meters. Even at small distances, properly shielded communication cable should be used and cable shielding should be grounded to the ship's structure at either the bus-master side or H235 interface side. If longer distances are to be bridged, RS232 is not suitable and RS485 should be used. RS485 cabling and bus termination For connection of the MODBUS module to the bus master, high quality shielded and twisted communication cable should be used. Cable shielding should be grounded at either the H235 interface side or the bus master side. The H235 module is not provided with a bus termination resistor. If the module is to be attached to the end of a network branch, it may be required to terminate the serial line with a suitable 120 Ohm resistor to match the network impedance. Although termination is many cases is not required, it will enhance communication reliability, especially when using long network cables or in situations where high levels of HF radiation may cause signal distortion.

12 Identification code The basic indicator assembly is designated by the code: AMTG 821/02. Every additional assembly which is fitted in the indicator is indicated in the type number by an additional two letter code. Following codes are valid: /LI /SA /PO /CO

: : : :

lcd display dual fixed and selectable level alarm outputs parallel data output 4-20 mA current output

Example: AMTG 821/02-LI/SA/CO: basic indicator with level indication, dual fixed level alarms and dual selectable alarms and 4-20 mA current output option boards fitted. Partnumber code complete remote level indicators: Type AMTG AMTG AMTG AMTG AMTG AMTG

Partnumber 821.02.100 821.02.103 821.02.105 821.02.106 821.02.107 821.02.108

821/02-IF 821/02-LI/SA 821/02-LI/PO 821/02-LI/CO 821/02-LI/SA/CO 821/02-LI/SA/PO

Partnumber code optional plug-in PCB's: Option board

Suffix

LCD display LI Parallel output board PO Alarm board (selectable) SA 4-20 mA current output CO

Version: November 2009 (0911)

Partnumber 821.02.X16REV/016A 821.02.005 821.02.007 821.02.008

50

©Henri Systems Holland B.V.

13 Mounting The remote level indicators can be fitted into rectangular panel cutouts of 90 mm vertical and 138 mm horizontal. The maximum panel thickness shall not exceed 10 mm. The instrument housing can be secured with the brackets supplied with the indicator. The minimum horizontal distance between two panel cut-outs from centre line to centre line shall not be less than 168 mm. The minimum vertical distance between the centre lines of the panel cut-outs shall not be less than 110 mm. The minimum required depth behind the panel is 200 mm. Warning:

The remote level indicators are designed for mounting in a non hazardous area such as cargo control rooms. Only the level transmission circuit (the communication circuit between level gauge and remote indicator) is certified intrinsically safe.

The remote level indicators are designed for operation in an ambient temperature range from 0-70°C. The minimum storage temperature is -25°C. However, level display on the LCD screen may become "syrupy" at temperatures below 5°C.

14 Intrinsically safety and cabling As required by IMO and international classification societies the electrical transmission circuit between level gauge and remote level indicator is certified intrinsically safe (certified by KEMA, The Netherlands). Intrinsically safety class is Ex II (1)G [EEx ia] IIC, certificate no. 03ATEX 1469. Intrinsically safe circuits are designed so that the maximum possible energy in such circuit is insufficient to ignite an explosive gas mixture. To maintain the intrinsically safe characteristics of the system the following conditions must be observed: 1. The maximum capacity of the cabling between level gauge and remote level indicator shall not exceed 160 nF (from core to core to shield). The electrical components inside the level gauge (transmitter, alarm switches) have a maximum capacity of 60 nF. 2. The maximum inductivity shall not exceed 13 mH. The maximum voltage on the transmission circuit is limited to 16 Volts by means of integrated Zener barrier circuits. The maximum current (short circuit of all transmission circuit cores) is limited to 50 mA by means of metal film resistors. The indicators have been designed to be supplied by a 12 Volt stabilized power source. Introducing higher voltages will not result in higher level transmission circuit output voltages and/or currents, but will increase power dissipation and may result in damaging the current protection fuse. (internal). Minimum supply voltage is approx. 11 Volts. The distance between the intrinsically safe terminals and other terminals at the back of the instrument casing is at least 50 mm. This distance should be maintained also in the intrinsically safe cabling to the level gauges. The output relay contacts of the optional level alarm PCB have a maximum contact rating of 1A @ 24 VDC/0.5A @ 120VAC.

The maximum switched voltage shall not exceed 125V and the maximum switch power shall not exceed 24W/60VA.

Version: November 2009 (0911)

51

©Henri Systems Holland B.V.

14.1 Cable requirements 1.

Between level gauge and remote level indicator: a. Minimum cross section per core 0.75 mm2 b. Maximum core resistance: 150 Ohm c. Maximum cable capacity from core to core or from core to shield: 160 nF (usually 0.2 nF/m) Number of cores per cable: a. for level transmission only: 5 cores b. for level transmission and 2 alarms: 7 cores It is recommended to use cables with 2 extra cores for spare. This allows future extensions. Shielded cables are preferred and often required by Class. Societies. Twisted pair cables, either overall- or pair-shielded, reduce radio frequent interference and are therefore preferred.

2.

Between power supply unit(s) and first indicator and from indicator to indicator: a. Minimum cross section per core: 1.5 mm2 b. Number of cores required: 2. It is recommended to install the power supply units as close as practically possible to the remote level indicators to keep short cables and reduce voltage drop.

3.

Grounding cables from indicator to common ships ground: a. Minimum cross section: 2.5 mm2 b. Number of cores required: 1. The grounding cable should not be linked to other indicators but should be connected directly to the ships' ground. Before connecting the transmission circuit, the ground cable should be fitted. It is not allowed to remove the grounding cable when the level transmission circuit connector is fitted and power is applied.

4.

Level alarm relay output circuit: a. Recommended cross section per core: 1.5 mm2 b. Number of cores required: 2-3 per output, depending on application. Connections:

5.

C = common NO = normally open NC = normally closed

4-20 mA current loop output: a. Minimum cross section per core: 1.5 mm2 b. Number of cores required: 2. The output is voltage carrying which means that it can drive un-powered devices immediately. By design the output minus connection is equalized to ground. If the output is to be connected to a non-galvanically separated input it is required to install an additional galvanic separator. It is not necessary that this separator is of an intrinsically safe design. In order to increase signal immunity to interference’s from other sources, it is recommended that the cables used are shielded and of a twisted pair type.

Version: November 2009 (0911)

52

©Henri Systems Holland B.V.

6.

Parallel data output: a. Minimum cross section core: 0.13 mm2. b. Number of cores required: 13. It is advised to use screened (flat) cable for both the 8 bit data-bus and the 5 bit address bus connections. Data output is in normal TTL level and non-addressed remote level indicators are in so called tri-state (high output impedance). Galvanic separation is not provided. "0" level is equalized to ships' ground.

7.

MODBUS H235 serial data output a. Recommended cross section per core: 0.75 mm2. b. Number of cores required: 2 The output signal is RS232C or RS485 compatible without handshaking and/or xon/xoff software flow control. Data format is Modicon's MODBUS binary protocol. Up to 32 units can be wired in parallel, where each unit is automatically and individually addressed through the serial port. The signal output port, both in RS232 and RS485 mode, is not galvanically separated.

15 Installation After the indicators have been fitted, the electrical connections can be made. (Cable requirements are stated in paragraph 14.1.) Depending upon the type and number of additional option boards installed, the back panel of the indicator can be fitted with several different connectors. Identification of the connectors is shown in figure 28. J2 J3 J4 J5 J7 J8 J10

: : : : : : :

Level alarm relay outputs 4..20 mA current loop output Spare Parallel output / address bus 12 Volt power supply input Level gauge connection Ground

For every available input and output, a corresponding plug is supplied to enable easy installation. Pin connections for all connectors are as follows (pin 1 is left, facing back-panel): J2:

Pin Pin Pin Pin Pin Pin Pin Pin Pin Pin Pin Pin

1 = level alarm 1, common 2 = level alarm 1, NC 3 = level alarm 1, NO 4 = level alarm 2, common 5 = level alarm 2, NC 6 = level alarm 2, NO 7 = level alarm 3, common 8 = level alarm 3, NC 9 = level alarm 3, NO 10 = level alarm 4, common 11 = level alarm 4, NC 12 = level alarm 4, NO

J3:

Pin 1 = 4..20 mA loop, signal (+) Pin 2 = 4..20 mA loop, ground (-)

Version: November 2009 (0911)

53

©Henri Systems Holland B.V.

J4:

Spare Pin 1 = spare Pin 2 = spare

J5:

Pin Pin Pin Pin Pin Pin Pin Pin Pin Pin Pin Pin Pin Pin Pin Pin

1 = data out, bit 1 2 = data out, bit 0 3 = data out, bit 3 4 = data out, bit 2 5 = data out, bit 5 6 = data out, bit 4 7 = data out, bit 7 8 = data out, bit 6 9 = ground 10 = ground 11 = address in, bit 0 12 = select MSB / LSB 13 = address in, bit 2 14 = address in, bit 1 15 = ground 16 = address in, bit 3

J7:

Pin 1 = +12V Pin 2 = 0V/ground

J8:

Pin Pin Pin Pin Pin Pin Pin Pin

1 2 3 4 5 6 7 8

= = = = = = = =

(A1) (A0) (A3) (A2) (A4)

level alarm 1 level alarm 2 transmitter channel A transmitter channel B transmitter channel C reference switch transmitter/switch supply (Exi) ground

15.1 Data output installation considerations When connecting any of the signal outputs to a host device, galvanic separation of the indicator output and host input needs to be provided. Modern signal output interfaces of central data acquisition systems in general are fitted with integral separation. In case there is any doubt whether or not the host computer input is suitable for direct connection, contact the manufacturer of the system.

16 Commissioning and initial calibration After completion of the installation of the level gauges, remote level indicators, power supply unit(s) and cabling, the system can be switched on and the remote level indicators can be synchronized with the level gauges. Depending upon the number and type of additional feature PCB's, the calibration procedure may consist of several proceedings. It is however advised to synchronize the common LCD level indicator first before calibrating any other circuit installed, as this indication can be used as a reference.

Version: November 2009 (0911)

54

©Henri Systems Holland B.V.

16.1 Calibration of level indicator (Rev. 3 LCD PCB’s) Before the remote level indicator can be calibrated, the local read-out of the level gauge should be adjusted as described in chapters 3.3 and following. Also the reference level switches should be adjusted as described in chapters 3.4.1 and 3.4.2. 1. 2. 3. 4. 5. 6.

7.

8. 9.

10.

11.

Switch on power. Hoist the float to top position. Check that the "SYNC" signal at the indicator front panel is on and the "FAULT" LED is off. As long as the "SYNC" LED is illuminated, the LCD display is blanked. Release the float and note both the local read-out and the remote level indicator read-out in at least two levels. If the pulse transmitter is wired correctly the remote indicator will roughly follow the values of the local indicator. If the indicator is not wired correctly it will run in the opposite direction and a large difference will be observed in read-outs. This can be corrected by interchanging connections 1 and 2 in the junction box of the level gauge or – if the direction of the LCD readout should work opposite to the direction of installed option-boards – by means of removing jumper J3 on the front of the LCD PCB. Determine the difference in local read-out and remote read-out with the float in bottom position. If the remote read-out shows a higher value than the local readout, the calculated difference should be subtracted from the remote indicator reference setting. If the remote read-out is lower, the calculated difference should be added to this value. Remove the front of the remote indicator and locate the position of the reference switches (right of display). The upper switch corresponds with the highest value (10.000 mm units) and the bottom switch corresponds to the lowest value (1 mm units). A small arrow indicates the actual setting on each switch. The indicator supports display two distinct fonts: the standard, large-size, bold sans-serif font and a simulated 7-segment font. Selection of the displayed font is done by removing or inserting jumper J2 on the front of the LCD PCB: when J2 is fitted, the large font is used; when J2 is removed, the simulated 7-segment font is used. When inserting or removing any jumper, the power to the indicator should be removed and re-applied in order for any changes to become effective! Mount the indicator front again and make sure that the thin flat cable is not kinked. Hoist the float to its top position and release the float once again. Check that the local and remote read-outs are correctly synchronized (max. error ± 2 mm.)

After an overhaul it may be necessary to re-synchronize the remote level indicator and local indicator again according to the above mentioned procedure. Always make sure that the reference switch closes at a level that is higher than the 100% filling level of the tank! Example: Innage read-out Initial reference value Lref = 12635 mm. Level shown at level gauge, float at bottom Lg = 00025 mm. Level shown at remote indicator, float at bottom Li = 00055 mm The remote indicator shows 00055 - 00025 = 30 mm too much. The new reference value must be: 12635 - 30 = 12605 mm.

Version: November 2009 (0911)

55

©Henri Systems Holland B.V.

Remark:As long as the SYNC signal at the indicator front is "on" the LCD display is switched off and blanked. The electronic counter is switched off, too. In this position no comparison can be made between local read-out and the remote read-out.

16.2 Level alarms The level alarm PCB has possibilities for 2 fixed alarms (AL1 and AL2), and 2 adjustable alarms (AL3 and AL4) The alarm option board is fitted with its own digital counter very much similar to the counter on the display unit. Consequently this board is able to operate even if the indicator PCB is faulty. Obviously a reference value should be set on this board too. This value is not necessarily equal to the reference value set on the indicator board. An explanation is given in the following. The indicator counter, although it has a 16-bit resolution, is configured such, that upon an overflow of the counter, the value "99999" is displayed. Down-going pulses reduce this value to 99998, 99997, etc. (For a 'normal' 16 bit counter, a down-pulse (subtract) on a counter value of 0 would cause it to go to 65535 = FFFF, 65534 = FFFE, etc.) The 16 bit counter on the alarm pcb sees the below “0” value as a level of 65535 mm and initiates the high level alarm (at the bottom!!!) It may be obvious now to see that it is very important that the counter on the alarm PCB never goes below “zero”. (99999 etc.) In innage read-out, the display may go “below zero” if a “sump” is fitted. In ullage read-out, the display may go “below zero” when ullage “0” equals deck height, the reference value would be less than zero. To prevent that the counter on the alarm board reaches below “0”, a value should be added (more than sump height) to the reference value and the alarm value(s). (in the innage example 1 m = 1000 mm is added) (in the ullage example 0.1 m = 100 mm is added) We will discuss two examples which will give sufficient insight to make every possible setup. Identical values are taken as in the previous examples.

Version: November 2009 (0911)

56

©Henri Systems Holland B.V.

A. Innage readout Reference value for indicator : 11604 mm Setting value will be 11604 + 1000 +1 = 12605 (1 = correction for comparator) High level alarm to be set at 10950 mm Setting value will be 10950 + 1000 = 11950 (1000 = below “0” correction) Reference setting: Because the reference value is to be set in binary, we need to calculate the binary equivalent for decimal 12605. This value is then set by means of two jumper fields of 8 jumpers each. To find the binary value, perform the following calculations (see also table 1): 1. Divide the reference value by 256 : 12605 / 256 = 49.2382.... 2. Determine the integer of the result : 49 This equals the value for the high-byte, which we will call H. DO NOT ROUND OFF! The integer of 49.9, for instance, would also be 49! 3. Determine the value of the low byte : 12605 – (49 x 256) = 61 Subtract the value of the high-byte from the initial reference value. Remember that the highbyte needs to be multiplied by 256! We will call this value L. 4. Determine the binary equivalent for both L and H: L = 00111101 H = 00110001 5. Set the jumpers on SW1 according to the L value. A '0' means a jumper in position, a '1' means no jumper installed on that position. 6. Set the jumpers on SW2 according to the H value. A '0' means a jumper in position, a '1' means no jumper installed on that position. The jumpers would now be set as follows:

SW1 REF L SW2 REF H ██::::█: ██::███: ↑ ↑ pin 1 pin 1 Alarm setting (AL3) Now the alarm jumper setting can be determined in a similar way: 1. Divide the required alarm level value by 256 : 11950 / 256 = 46.679.... 2. Determine the integer of the result : 46 This equals the value for the high-byte, which we will call H. Again, DO NOT ROUND OFF! 3. Determine the value of the low byte : 11950 - 46 x 256 = 174 Subtract the value of the high-byte from the initial reference value. Remember that the highbyte needs to be multiplied by 256! We will call this value L. 4. Determine the binary equivalent for both L and H L = 10101110 H = 00101110

Version: November 2009 (0911)

57

©Henri Systems Holland B.V.

5. Set the jumpers on SW3 according to the L value. A '0' means a jumper in position, a '1' means no jumper installed on that position. 6. Set the jumpers on SW4 according to the H value. A '0' means a jumper in position, a '1' means no jumper installed on that position. The jumpers would now be set as follows for adjustable alarm 1:

SW3 AL 3 L :█:█:::█ ↑ pin 1

SW4 AL 3 H ██:█:::█ ↑ pin 1

Alarm setting (AL4) For adjustable alarm 4, SW5 and SW6 need to be used instead of SW3 and SW4. SW5 is the low byte (L), SW6 the high byte (H).

Switch Mode (SW7 with jumpers) For each of the four alarms, the reset action is to be defined on jumpers SW7. Each alarm has two jumpers. When a jumper is placed in the odd numbered position, the alarm relay is de-energized when the accept push button is actuated. In the even numbered position, the alarm relay is de-energized only when the float is manually hoisted into top position. For alarm number 1, pins 1 and 2 of SW7 are to be used, for alarm number 2 pins 3 and 4, and so forth. It is required that a jumper is placed in only one of the two possible positions. Switch Mode (SW7 with solder strips) For each of the four alarms, the reset action is to be defined with solder strips on SW7. Each alarm has one solder strip, which short circuits the pin contact. When the solder strip is placed, the alarm relay is de-energized when the accept push button is actuated. (RE: AL1 in switch sequence) RE: the red alarm light on the remote indicator front panel remains on. When the solder strip is removed, the alarm relay is de-energized only when the float is manually hoisted into top position. (RE: AL2 in switch sequence) For alarm 1, pin 1 is used, for alarm 2, pin 3 and so on. SW7 (default settings)

:█:█:█:█ ↑ pin 1

Version: November 2009 (0911)

58

©Henri Systems Holland B.V.

Switch mode: AL1 with jumper; AL2 without the jumper

16.3 4-20 mA current loop Preparing the PCB setup Before installing the PCB into the remote level indicator, the following data has to be collected, calculated and/or determined: 1. Upper dead zone measured from reference level in mm 2. Active measuring range in mm 3. Normal or inverted output mode 4. Current output in FAIL mode (fail high/low) 5. Current output in REF mode (ref high/low) 6. Failure Current output (value of the failure indication; 4/20 or 0/24 mA)

Version: November 2009 (0911)

59

©Henri Systems Holland B.V.

SW1=Dead zone = 20 mA

SW2=Active measuring

= 4 mA 1 – Upper dead zone (SW1-1 to 1-4) The level gauge is fitted with a magnetically operated switch that switches when the float is in its top position. The height at which this switch is closed is referred to throughout this manual as the ‘reference level’. Generally, the reference level is above the maximum tank level, i.e. the level corresponding to 100% tank capacity, because the level gauge is fitted on top of a dome, trunk or pipe construction. However, in most cases the maximum or minimum output current (depending upon the type of measurement: ullage or level) is required to be generated at 100% tank filling and not at a level greater than that. The current loop output board offers the possibility to create a ‘dead zone’ above the 100% tank level so that the output current will be driven to its maximum or minimum value at exactly 100% filling. When the float moves further upward, the current will remain unchanged until the reference switch is opened when the float is hoisted to its home position. Calculation of the dead zone is fairly simple and illustrated in two examples following this description. 2 – Active measuring range (SW2-1 to 2-5) The active measuring range defines the total height over which the current output is controlled by the electronics. In general, this value would be equal to the height of the tank but under certain conditions may be somewhat different. Again, the examples given will illustrate how this value is generally determined. 3 – Normal or inverted output The output current generated by the electronics circuitry is normally 20 mA when the float is at 100% tank filling level and 4 mA when the float is lowered to the tank bottom. The magnitude of the output is thus linear to the liquid level inside the tank. In cases where the output current should decrease when the liquid level rises, the output may be inverted so that the output level is linear to the ullage. The instrument that receives the output current generally defines whether normal or inverted output is required. Selection is done by simply setting a small switch on the board. (DIP-switch SW3-2, normal=ON) 4 – FAIL mode In case of a transmitter, cabling or interface failure, the remote level indicator will go into FAIL mode: the LCD display, when fitted, will blank and a red FAULT indication LED will illuminate on the front panel. When a FAIL situation occurs, the current output can be programmed to go either to the maximum or the minimum level (fail high level or low level)

Version: November 2009 (0911)

60

©Henri Systems Holland B.V.

Setting is done with SW3-4 (ON=low level current, default; OFF=high level current) and JP1/JP2 for the value of the current (0/4 or 20/24 mA) 5 – REF mode When the float is hoisted to its home position, i.e. all the way up, the reference switch inside the level gauge will open, and the analog output will be frozen on the high or low level value. (4 or 20 mA) selection is done with SW3-3 ( 100%(high)=ON, 0%(low)=OFF, default). 6 – Failure Current output (minimum and maximum range) the measuring range of the current output stage is ‘4 .. 20 mA The Fail indication can be set outside of this range to 0 or 24 mA, this is done with jumpers JP1 and JP2, and SW3-4 Setting the PCB switches On the component side of the PCB, a number of switches and jumpers is available so that the board can be programmed to perform the exact actions as described in this paragraph. In the figure below, a simplified layout of the board is given

Figure 1

SW1-1 .. SW1-4 Upper dead zone in mm. SW1-1 is the most significant -, SW1-4 the least significant digit. SW2-1 .. SW2-5 Active measuring range in mm. SW2-1 is the most significant-, SW2-5 the least significant digit. Mode Setting DIP SW3 -1 /Test -2 /Direction -3 /Reference -4 /Failure output

ON Normal mode Normal, 20 mA=top High level value Low level value

OFF Test mode Inverse, 4 mA=top Low level value High level value

4 or 20 mA 0, 4, 20, or 24 mA Default

Fail current setting

Version: November 2009 (0911)

61

©Henri Systems Holland B.V.

JP1/2 4-20 mA 0-20 mA 0-24 mA

JP1 | O O―O | O—O O | O—O O

JP2 | O—O O | O O―O | O—O O

=Default

JP3 should be fitted only if no LCD PCB is fitted in the remote level indicator. When an LCD unit is fitted, JP3 should be left open. Example 1 We consider a situation as drawn in figure 2 (below). The level gauge is an innage (level) measurement type gauge. The reference switch is set at 16.250 mm on the local readout, whereas the maximum liquid level at 100% tank filling is at 15.825 mm. When the float is lowered to the tank bottom, resting on a small support, the local readout indicates 188 mm as has been set during local readout calibration (for details, refer to instruction manual of level gauge). The current output board is to be configured so that an output current of 20 mA is obtained at 100% tank filling and 4 mA at 0% tank filling. Furthermore, 4 mA output is required when the float is hoisted to its home position, and 20 mA in case of a transmitter failure.

1. Calculation of dead zone When the float travels down from home position, the reference switch is operated at 16.250 mm local indication. The current output should remain 20 mA until the local readout is 15.825 mm. The dead zone thus equals 16.250 – 15.825 = 425 mm. This

Version: November 2009 (0911)

62

©Henri Systems Holland B.V.

value is to be set on rotary BCD switches SW1-1 .. SW1-4 as follows: SW1-1 0 SW1-2 4 SW1-3 2 SW1-4 5 2. Calculation of active measuring range When determining the active measuring range, we have to take into consideration that the float, in this example, can not travel further downward than the float support at the tank bottom. However, the current output should be 4 mA when the tank could be measured empty; this means, that if the float is resting on its support, the output current would be somewhat more than 4 mA in this example. Thus, we require to set the active range to 15.825 mm rather than 15.637 mm! The SW2 switches therefore require to be set as follows: SW2-1 1 SW2-2 5 SW2-3 8 SW2-4 2 SW2-5 5 3. Output direction In this example, we want the current to increase as the float moves up inside the tank, i.e. normal operation direction. DIP-switch SW3-2 therefore should be set to ON 4. FAIL operation When DIP-switch SW3-4 is switched to OFF position, the output current will be driven to its maximum value when a transmitter fail occurs. 5. REF operation When the float is fully hoisted, a current of 4 mA is required. DIP-switch SW3-3 therefore has to be switched to its OFF position. 6. Output range To set the output to plain 4 .. 20 mA, JP1 is to be set to its rightmost position (connecting pins 1 and 2) and JP2 to its leftmost position (connecting pins 2 and 3). It is essential that one makes sure that switch SW3-1 is set to ON position in order to set the board to normal operation mode; when set to OFF, the test mode is invoked Example 2 The situation for this example is sketched in figure 3 (below). The level gauge is an ullage (empty space) measurement type gauge, which has been adjusted so that the local indication is exactly 0 mm when the float is at the 100% filling level. The reference switch is set at 98.825 mm on the local readout. The tank bottom has a small sump in which the float rests when lowered fully; the local readout, in that case, is 12.429 mm. This is 24 mm below the reference plane of the tank bottom. In this situation, the current output board has to be configured so that an output of 20 mA is reached when the tank is empty and 4 mA when the tank is filled to 100% capacity. Furthermore, an output current of 0 mA is required when a FAIL situation occurs, and 20 mA when the float is hoisted to its topmost position.

Version: November 2009 (0911)

63

©Henri Systems Holland B.V.

1. Calculation of dead zone Determination of the dead zone is similar as described in the previous example: the output current should change only after the float has travelled down to a local indication of 0 mm. Because of the mechanical design of the local level indicator, it will indicate 99999 rather than ‘–1’, so the dead zone in this example is calculated as 100000 – 98825 = 1175 mm.

This means that switches SW1-1 .. SW1-4 are set to: SW1-1 1 SW1-2 1 SW1-3 7 SW1-4 5 2. Calculation of active measuring range In this example, the small sump has to be taken into consideration when calculating the active measuring range. Because the output should be 20 mA when the tank is empty, the output should be frozen to this value even if the float travels down further into the sump. From the data given in the description, the height of the tank, and thus our active range, can be calculated as follows: range = 12429 – 24 = 12405 mm This value is set to switches SW2: SW2-1 1 SW2-2 2 SW2-3 4 SW2-4 0 SW2-5 5 3. Output direction In this example, we want the current to decrease as the float moves up inside the tank, i.e. inverted operation direction. DIP-switch SW3-2 therefore should be set to OFF.

Version: November 2009 (0911)

64

©Henri Systems Holland B.V.

4. FAIL operation Because we want the current to go to its minimum value when a fail situation is detected DIP-switch SW3-4 is to be switched OFF. Furthermore, the current output range has to be adjusted so that 0 mA drive is enabled (see under 6. Output range). 5. REF operation When the float is fully hoisted, a current of 20 mA is required. Because the output has been inverted already by SW3-2 setting, DIP-switch SW3-3 requires to be switched to its OFF position to obtain this functionality. 6. Output range For 0 .. 20 mA operation (at least: 0 mA for FAIL) J1 has to be set to its leftmost position (shorting pins 2 and 3) and J2 to its rightmost position (shorting pins 1 and 2). Connection of 4/20 mA Output

J3 1= + 2= ―

Specifications Measuring range : 65 meters Output : 04..20 mA (measuring), active. Maximum Load : Rloop < 450Ω Maximum output voltage : U(open loop)