KROHNE BM26 User Manual

Handbook

BM 26 BASIC/ADVANCED

BM 26 BASIC/ADVANCEDBM 26 BASIC/ADVANCED

Stainless Steel Bypass Level Indicators for applications up to 40 bar / 580 psi

HandbookHandbook

: IMPRINT :::::::::::::::::::::::::::::::::::::::

BM 2

Subject to change without notice.

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BM 26 BASIC/ADVANCED

CONTENTS

1 Safety instructions 5

1.1 Intended use ..................................................................................................................... 5

1.2 Certification ...................................................................................................................... 5

1.3 Safety instructions from the manufacturer ..................................................................... 6

1.3.1 Disclaimer ............................................................................................................................... 6

1.3.2 Product liability and warranty ................................................................................................ 7

1.3.3 Information concerning the documentation........................................................................... 7

1.3.4 Warnings and symbols used................................................................................................... 8

1.4 Safety instructions for the operator................................................................................. 8

2 Device description 9

2.1 Scope of delivery............................................................................................................... 9

2.2 Device description .......................................................................................................... 10

2.3 Nameplates .................................................................................................................... 11

2.3.1 Visual Check.......................................................................................................................... 11

2.3.2 Nameplates........................................................................................................................... 11

2.3.3 Other device data .................................................................................................................. 14

3 Installation 15

3.1 Storage ........................................................................................................................... 15

3.2 Transportation ................................................................................................................ 16

3.3 Remove all packing before installation ......................................................................... 16

3.4 General requirements .................................................................................................... 18

3.4.1 Pressure and temperature ranges....................................................................................... 18

3.4.2 How to attach the bypass level indicator to the tank ........................................................... 19

3.5 Level indicator column................................................................................................... 21

3.6 Optional analog transmitter ........................................................................................... 22

3.7 Optional limit switch....................................................................................................... 23

3.8 Electromagnetic compatibility ....................................................................................... 26

4 Electrical connections 27

4.1 Optional analog transmitter ........................................................................................... 27

4.2 Optional limit switches ................................................................................................... 29

4.3 Protection category ........................................................................................................30

5 Start-up 31

5.1 Start-up checklist........................................................................................................... 31

5.2 Operating concept ..........................................................................................................31

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CONTENTS

BM 26 BASIC/ADVANCED

6 Operation 32

6.1 Local display options ......................................................................................................32

6.1.1 Level indicator column ......................................................................................................... 32

6.1.2 Analog transmitter (option) .................................................................................................. 33

6.2 Errors.............................................................................................................................. 37

6.2.1 Error indication ..................................................................................................................... 37

6.2.2 Error handling....................................................................................................................... 38

7 Service 41

7.1 Periodic maintenance..................................................................................................... 41

7.2 Keep the device clean..................................................................................................... 41

7.3 How to replace device components ............................................................................... 41

7.3.1 Service warranty ................................................................................................................... 41

7.4 Availability of services .................................................................................................... 42

7.4.1 General notes........................................................................................................................ 42

7.4.2 List of spare parts................................................................................................................. 42

7.4.3 List of accessories ................................................................................................................ 43

7.5 Availability of services .................................................................................................... 43

7.6 Returning the device to the manufacturer..................................................................... 44

7.6.1 General information.............................................................................................................. 44

7.6.2 Form (for copying) to accompany a returned device............................................................ 45

7.7 Disposal .......................................................................................................................... 45

8 Technical data 46

8.1 Measuring principle........................................................................................................46

8.2 Technical data: general information .............................................................................. 47

8.3 Technical data: optional analog transmitter.................................................................. 51

8.4 Technical data: optional limit switches.......................................................................... 56

8.5 Basic version: Dimensions and weights ........................................................................ 58

8.6 Advanced version: Dimensions and weights.................................................................. 66

8.7 Analog transmitter: Dimensions and weight ................................................................. 74

8.8 Support bracket option: Dimensions and weight........................................................... 75

8.9 Guidelines for maximum operating pressure................................................................ 76

8.10 Floats ............................................................................................................................ 78

9 Appendix 79

9.1 Liquid level offset: description....................................................................................... 79

9.2 Liquid level offset: correction data ................................................................................ 80

9.3 Glossary .......................................................................................................................... 83

9.4 Order code ...................................................................................................................... 84

9.5 Spare parts code ............................................................................................................ 92

10 Notes 94

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BM 26 BASIC/ADVANCED

1.1 Intended use

This magnetic level indicator measures the level or volume of liquids.

It is installed next to open or pressurized tanks. With the applicable options, it is resistant to difficult service conditions and liquids that are poisonous, flammable, or that cause corrosion.

CAUTION!

Responsibility for the use of the measuring devices with regard to suitability, intended use and corrosion resistance of the used materials against the measured fluid lies solely with the operator.

INFORMATION!

The manufacturer is not liable for any damage resulting from improper use or use for other than the intended purpose.

1.2 Certification

SAFETY INSTRUCTIONS 1

In accordance with KROHNE’s commitment to customer service and safety, the level indicators

described in this handbook meet the following safety requirements:

• EMC Directive 2004/108/EC in conjunction with EN 61326-1: 2006

• Low Voltage Directive 2006/95/EC in conjunction with EN 61010-1: 2001

• Pressure Equipment Directive 97/23/EC in conjunction with CODAP® 2010

INFORMATION!

The optimized design of the Basic version is not subject to PED test requirements (CE marking is not applicable). The Advanced version agrees with the requirements for CE marking. The Low Voltage Directive is only applicable to limit switches (non-NAMUR option).

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1 SAFETY INSTRUCTIONS

1.3 Safety instructions from the manufacturer

1.3.1 Disclaimer

The manufacturer will not be liable for any damage of any kind by using its product, including, but not limited to direct, indirect or incidental and consequential damages.

This disclaimer does not apply in case the manufacturer has acted on purpose or with gross negligence. In the event any applicable law does not allow such limitations on implied warranties or the exclusion of limitation of certain damages, you may, if such law applies to you, not be subject to some or all of the above disclaimer, exclusions or limitations.

Any product purchased from the manufacturer is warranted in accordance with the relevant product documentation and our Terms and Conditions of Sale.

The manufacturer reserves the right to alter the content of its documents, including this disclaimer in any way, at any time, for any reason, without prior notification, and will not be liable in any way for possible consequences of such changes.

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1.3.2 Product liability and warranty

Bypass level indicators from KROHNE are designed solely for measuring the level and volume of liquids.

Responsibility as to suitability and intended use of these level indicators rests solely with the operator. The supplier does not accept any liability resulting from misuse by the operator. Improper installation and operation of the level transmitters may lead to loss of warranty. In

addition, the “General conditions of sale“ which forms the basis of the purchase agreement are

applicable.

1.3.3 Information concerning the documentation

To prevent any injury to the user or damage to the device it is essential that you read the information in this document and observe applicable national standards, safety requirements and accident prevention regulations.

If this document is not in your native language and if you have any problems understanding the text, we advise you to contact your local office for assistance. The manufacturer can not accept responsibility for any damage or injury caused by misunderstanding of the information in this document.

SAFETY INSTRUCTIONS 1

This document is provided to help you establish operating conditions, which will permit safe and efficient use of this device. Special considerations and precautions are also described in the document, which appear in the form of underneath icons.

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1 SAFETY INSTRUCTIONS

1.3.4 Warnings and symbols used

Safety warnings are indicated by the following symbols.

DANGER!

This information refers to the immediate danger when working with electricity.

DANGER!

This warning refers to the immediate danger of burns caused by heat or hot surfaces.

DANGER!

This warning refers to the immediate danger when using this device in a hazardous atmosphere.

DANGER!

These warnings must be observed without fail. Even partial disregard of this warning can lead to serious health problems and even death. There is also the risk of seriously damaging the device or parts of the operator's plant.

BM 26 BASIC/ADVANCED

WARNING!

Disregarding this safety warning, even if only in part, poses the risk of serious health problems. There is also the risk of damaging the device or parts of the operator's plant.

CAUTION!

Disregarding these instructions can result in damage to the device or to parts of the operator's plant.

INFORMATION!

These instructions contain important information for the handling of the device.

LEGAL NOTICE!

This note contains information on statutory directives and standards.

• HANDLING

HANDLING

HANDLINGHANDLING

This symbol designates all instructions for actions to be carried out by the operator in the specified sequence.

i RESULT

RESULT

RESULTRESULT This symbol refers to all important consequences of the previous actions.

1.4 Safety instructions for the operator

WARNING!

In general, devices from the manufacturer may only be installed, commissioned, operated and maintained by properly trained and authorized personnel. This document is provided to help you establish operating conditions, which will permit safe and efficient use of this device.

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2.1 Scope of delivery

INFORMATION!

Check the packing list to see if you have received all that you require. The device will be delivered in one box.

INFORMATION!

Inspect the cartons carefully for damages or signs of rough handling. Report damage to the carrier and to the local office of the manufacturer.

DEVICE DESCRIPTION 2

Figure 2-1: Scope of delivery

1 Measuring chamber with the indicator column and optional indicator scale 2 Optional analog transmitter 3 Optional limit switches (not attached to the device) 4 Magnet (to set the indicator column to zero after installation) 5 Quick Start and Handbook

INFORMATION!

No special tools, no training required!

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2 DEVICE DESCRIPTION

2.2 Device description

Magnetic level indicators have a measuring chamber that contains a magnetic float. It is attached vertically to the side of open or pressurized tanks. A level indicator is attached adjacent to the measuring chamber. As the float moves up and down, it rotates a column of flaps inside the glass tube of the indicator. If an analog level transmitter is also attached adjacent to the measuring chamber, it is possible to have an output current that can be monitored from a remote station. Optional bistable switches let the user monitor important measurement limits.

BM 26 BASIC/ADVANCED

The measuring chamber of the Basic 232 psig (depending on the length of the chamber). It is unnecessary to test the measuring chamber according to PED 97/23/EC as it does not have to comply with CE marking

requirements. It is also ideal for measuring liquids with a density ≥0.8 kg/l / ≥49.9 lb/ft³ and temperatures up to 150°C/ 300°F.

The Advanced

Advanced version is ideal for measuring liquids with density range of 0.58...2.0 kg/l /

AdvancedAdvanced

36.2...124.8 lb/ft³, temperatures up to 300°C/ 570°F or pressures up to 40 barg / 580 psig.

Basic version has a maximum operating pressure of 16 barg /

BasicBasic

WARNING!

Pressure Equipment Directive 97/23/EC data

•

This device is designed to function at near constant pressure conditions. It is not designed for operating conditions where vibration or fatigue stress is present.

•

Events that are not taken into account in the calculations include exceptional risks such as: earthquakes, bad weather, fire etc.

•

The standard design calculation does not take into account the theoretical coefficient of corrosion. The product circulating in the device must not have properties that give rise to surface erosion.

•

Our conformity declaration is limited to the parts of the device that are pressurized. It does not include parts that can be dismantled (valves, ...).

You can also order these accessories:

• Limit switches

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BM 26 BASIC/ADVANCED

2.3 Nameplates

INFORMATION!

Look at the device nameplate to ensure that the device is delivered according to your order. Check for the correct supply voltage printed on the nameplate.

2.3.1 Visual Check

DEVICE DESCRIPTION 2

Figure 2-2: Visual check

• Check the delivery for damage.

• Are all the wetted components (chamber, flanges and gaskets) resistant to the product in the

tank?

• Compare the data on the nameplate with your order data.

2.3.2 Nameplates

Figure 2-3: Location of device nameplates

1 Measuring chamber nameplate 2 Analog transmitter nameplate 3 Limit switch nameplate (housing cover) 4 Limit switch nameplate (housing)

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2 DEVICE DESCRIPTION

Figure 2-4: Basic version: Non-Ex nameplate

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Figure 2-5: Advanced version: Non-Ex nameplate

1 Customer tag number 2 Measuring tube volume in litres 3 Maximum allowable pressure (P

4 Factory serial number 5 Purchase order number 6 Model name and number 7 Designation code (VF code given in the order) 8 Year of manufacture 9 Maximum allowable temperature (T

10 Test pressure (P

ment Directive 97/23/EC.

at 20°C) - if the device agrees with the requirements of Categories I, II or III of the Pressure Equip-

)

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Figure 2-6: Limit switch: Non-Ex nameplate (housing cover)

1 Non-NAMUR option 2 NAMUR option 3 Model 4 Designation code (VF code given in the order) 5 Date of manufacture 6 Factory serial number and bar code 7 Electrical data

DEVICE DESCRIPTION 2

Figure 2-7: Limit switch: Non-Ex nameplate (housing)

1 Non-NAMUR option 2 NAMUR option 3 Electrical schema 4 Factory serial number

Figure 2-8: Analog transmitter: Non-Ex nameplate

1 Model 2 Designation code (VF code given in the order) 3 Date of manufacture 4 Factory serial number 5 Input voltage

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2 DEVICE DESCRIPTION

2.3.3 Other device data

The supplier's bottom logo plate has a sticker:

Figure 2-9: Other device data

1 Float data sticker

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Figure 2-10: Float data sticker

1 Test pressure, PT, in bar 2 Maximum allowable pressure, PS, in bar 3 Float drawing number 4 Float material

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3.1 Storage

INSTALLATION 3

Figure 3-1: Storage conditions

1 Do not keep the device in a vertical position before installation. 2 Put the device on its side. 3 Storage temperature range: -50…+80°C/ -58…+176°F

• Store the device in a dry and dust-free location.

• Store the device in its original packing.

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3 INSTALLATION

3.2 Transportation

Figure 3-2: Transportation

WARNING!

The indicator column is made of Pyrex If you do not lift the device carefully, you can cause damage to the device.

glass.

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3.3 Remove all packing before installation

CAUTION!

Make sure that the measuring chamber does not contain unwanted objects (dirt etc.)

How to remove the float lock pin (devices with side process connections)

Figure 3-3: How to remove the float lock pin (devices with side process connections)

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How to remove the float lock pin (devices with side process connections)

1 Check the measuring chamber for a red sticker next to the bottom side process connection.

i Sticker text: ATTENTION! Take away transport safety device for float.

2 Remove the adhesive tape around the top and bottom process connections. 3 Remove the plastic protection from the top and bottom process connections. 4 Find the lock pin. 5 Remove the lock pin with a pair of pliers.

How to put the float in the measuring chamber

INSTALLATION 3

Figure 3-4: How to put the float in the measuring chamber (if it is delivered separately)

1 Put the float in here 2 Float 3 The float data (date of manufacture, P

the measuring chamber

, float material etc.) must be at the top of the float when you put the float in

s/Pt

How to put the float in the measuring chamber (if it is delivered separately)

• Remove the bottom blind flange or plug (if the basic version has the 1¼¨ drain option).

• Put the top of the float (the float data is on the top part of the float) in the measuring chamber

first.

• Align the gaskets.

• Tighten the nuts on the blind flange to the correct torque (11 Nm in operating conditions,

23.5 Nm in test conditions). The 1¼¨ plug must be tightened in agreement with good

engineering practice.

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3 INSTALLATION

3.4 General requirements

3.4.1 Pressure and temperature ranges

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1 Process temperature

Basic version: -40…+150°C/ -40…300°F Advanced version: -40...+300°C/ -40…570°F Ex devices: refer to supplementary instructions

2 Maximum process pressure

Basic version: 16 barg / 232 psig (depends on the length of the measuring chamber. For more data, refer to

for maximum operating pressure

Advanced version: 40 barg / 580 psig (according to the flange pressure rating. For more data, refer to

maximum operating pressure

3 Ambient temperature

Non-Ex devices: -40…+80°C/ -40…+176°F Ex devices: refer to supplementary instructions

on page 76).

Guidelines

Guidelines for

WARNING!

Refer to the operating conditions data on the device nameplate. The data is applicable to that device.

WARNING!

PED 97/23/EC requirement:

PED 97/23/EC requirement: External pressure must be equal to atmospheric pressure.

PED 97/23/EC requirement:PED 97/23/EC requirement:

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3.4.2 How to attach the bypass level indicator to the tank

INSTALLATION 3

Figure 3-5: How to attach the bypass level indicator to the tank

1 Optional isolation valve 2 Optional vent 3 Optional drain with isolation valve

Obey the instructions that follow:

• Select bolts and gaskets (not supplied) that agree with the pressure rating of the process connection and the operating pressure.

• Install the bypass level indicator vertically on the tank.

• Make sure that there is no contamination (dirt etc.) or unwanted objects in the measuring

chamber.

• Make sure that mechanical loadings do not cause damage to the process connections. If necessary, put supports on the device.

• Install shut-off valves so that the device can be cleaned separately from the tank. Drain the device only when it is isolated from the tank.

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3 INSTALLATION

Figure 3-6: Stay away from the process connections

WARNING!

Stay away from the process connections. If you stand on the process connections, you can cause damage to the device and the installation.

BM 26 BASIC/ADVANCED

DANGER!

Make sure that the outer surface temperature of the device is not more than 60

surface temperature is more than 60

C / 140°F, use the device with precautions that agree with

C / 140°F. If the

Health and Safety rules and regulations.

WARNING!

Pressure Equipment Directive 97/23/EC data

•

The process connections must be attached correctly to prevent mechanical stress. The axis of the process connection must be parallel to and centred with the axis of the tank's process connections. Tighten the process connections in agreement with the design code.

•

The user must take necessary steps to protect the installed device from shock waves (water hammer). A pressure limiting valve must protect the installation.

•

The effective pressure of the installation (the maximum permitted by the pressure limiting valve) must never be greater than the maximum permitted pressure, P

device nameplate.

•

Make sure that the parts in contact with the fluid are compatible with the fluid and conform to the ageing characteristics of the measurement environment and the fluid used. These have either been recommended in the instructions or form the subject of a particular specification in the contract.

•

The external pressure, P

•

If stainless steel devices are more than 6 m / 20 ft high, we recommend more anchoring

, must be equal to atmospheric pressure, P

ext

points.

, marked on the

atmos

ext

= P

atmos

CAUTION!

Before you fill the tank, make sure that the column of rotating flaps is set to zero (the flaps are all black). If not, the device may incorrectly indicate the level.

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BM 26 BASIC/ADVANCED

Figure 3-7: Set the indicator column to zero

1 Magnet - point the red end of the magnet at the glass tube

Equipment needed:

• Magnet (supplied with the device)

INSTALLATION 3

How to make sure the column of rotating flaps is set to zero

• Hold the magnet in front of the glass tube at the bottom of the indicator column.

i Make sure the red end of the magnet points at the glass tube.

• Move the magnet slowly up to the top the glass tube.

i The flaps all turn to black. The indicator column is set to zero. You can now fill the tank.

3.5 Level indicator column

The level indicator column is attached to the measuring chamber before delivery. Customer order data is used to calibrate its position. No other adjustment is necessary.

CAUTION!

Customer order data is used to calibrate the device. If liquid density changes, the device will not measure correctly. Please contact our nearest sales office for advice.

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3 INSTALLATION

3.6 Optional analog transmitter

The analog transmitter is attached to the measuring chamber before delivery. Customer order data is used to calibrate its position. No other adjustment is necessary.

WARNING!

Too much heat can cause damage to the analog transmitter. If the process temperature is more

than 120 the process temperature is more than 150 transmitter.

C / 250°F, put insulation between the bypass chamber and the analog transmitter. If

BM 26 BASIC/ADVANCED

C / 300°F, do not cover any part of the analog

Figure 3-8: Analog transmitter and insulation for the bypass chamber

1 Analog transmitter 2 Bypass chamber (cross-section) 3 If temperature is more 120°C/ 250°F, put insulation between the bypass chamber and the analog transmitter 4 Insulation (cross-section). If temperature is more 150°C/ 300°F, do not cover any part of the analog transmitter with

insulation.

CAUTION!

Do not move the analog transmitter. If you adjust the position of this device, the current output will be incorrect.

CAUTION!

Customer order data is used to calibrate the device. If liquid density changes, the device will not measure correctly. Please contact our nearest sales office for advice.

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3.7 Optional limit switch

INFORMATION!

The level switches are not attached to the device before delivery. Remove the switches from the packing and obey the instructions that follow.

WARNING!

Too much heat can cause damage to the limit switch. If you put insulation around the bypass level indicator, do not cover the limit switch housing. Make sure that there is approximately

15 mm / 0.6

of empty space between the limit switch and the insulation.

INSTALLATION 3

Figure 3-9: Limit switches and insulation for the measuring chamber

1 Limit switch housing 2 Insulation around the measuring chamber (cross-section) 3 Measuring chamber (cross-section)

Empty space between the limit switch and the insulation for the measuring chamber, a ≥15 mm / 0.6¨.

CAUTION!

If liquid density changes, the switch will not detect level correctly. Recalculate the position of the switch according to the true liquid density and repeat the installation procedure that follows.

CAUTION!

The switching point of the switch when the level increases is not in the same as the switching point of the switch when the level decreases. Does the limit switch have to be open when the float is above (for HIGH limit switches) or below (for LOW limit switches) the switching point? For more data, refer to Definition of switching point offset

Definition of switching point offset.

Definition of switching point offsetDefinition of switching point offset

WARNING!

If you put insulation around the bypass level indicator, do not cover the limit switch housing. Too much heat can cause damage to the limit switch.

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3 INSTALLATION

Figure 3-10: How to attach a limit switch

1 Limit switch 2 Switching point centreline 3 Level indicator and optional measuring scale 4 Limit switch clamp

Equipment needed:

• Large slotted tip screwdriver (not supplied)

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Installation procedure

• Use the clamp to attach the limit switch to the measuring chamber. Do not tighten the clamp.

i The cable gland must be at the bottom of the housing.

• Move the limit switch until the switching point centreline is at the level required. Refer to the

level indicator scale to help you position the limit switch.

i If the indicator column does not have the scale option, it will be necessary to calculate the

vertical offset of the float magnet in relation to the level of the liquid (depends on the liquid density). Adjust the switch position for the float magnet offset. For the vertical offset tables, refer to the appendix in the Handbook.

• Adjust the switch position for the switching point offset.

i If the limit switch is set to LOW limit

LOW limit (the switch is open

LOW limitLOW limit

open when the float is below the

openopen switching point), move the switch up a small distance to adjust for the offset. If the limit switch is set to HIGH limit

HIGH limit (the switch is open

HIGH limitHIGH limit

open when the float is above the switching point),

openopen move the switch down a small distance to adjust for the offset. For more data, refer to Definition of switching point offset

Definition of switching point offset and Switching point offset values

Definition of switching point offsetDefinition of switching point offset

Switching point offset values.

Switching point offset valuesSwitching point offset values

• Tighten the limit switch clamp.

WARNING!

Make sure the cable gland is on the bottom the housing and is tight to stop liquid entering the housing.

INFORMATION!

Liquid level offset

Liquid level offsetLiquid level offset For a description of the liquid level offset, refer to Liquid level offset: description on page 79

the graphs and other correction data, refer to

Liquid level offset: correction data on page 80

. For

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Definition of switching point offset

Figure 3-11: Switching point offset

1 Zero point of the limit switch 2 Zero point of the limit switch 3 Float and float magnet (switching point is in relation to the top of the magnet) 4 True switching point above a limit switch (the switch is open when the liquid level goes above this point - a HIGH limit

switch)

5 True switching point below the limit switch (the switch is open when the liquid level goes below this point - a LOW limit

switch)

INSTALLATION 3

HIGH limit

HIGH limitHIGH limit

LOW limit

LOW limitLOW limit

Switching point offset values

Conditions Switching point offset, a

mm inches

When the switch must be open above the switching point (a HIGH limit move the switch below the switching point:

When the switch must be open below the switching point (a LOW limit move the switch above the switching point:

HIGH limit switch),

HIGH limitHIGH limit

LOW limit switch),

LOW limitLOW limit

15 0.6

0 0

Installation of a limit switch for float failure detection

• Make sure the measuring chamber is empty and the float is in the chamber.

• Attach a limit switch to the bottom of the measuring chamber. Do not tighten the clamp.

• Connect the limit switch to the electrical circuit. Make sure that it is set to LOW limit

data, refer to

Optional limit switches

on page 29.

LOW limit. For more

LOW limitLOW limit

• Energize the electrical circuit.

• Lift the limit switch up the measuring chamber until the limit switch status changes to open

open.

openopen

• Hold the limit switch tightly in this position and tighten the clamp.

i The limit switch is in the correct position.

INFORMATION!

The float will go to the bottom of the measuring chamber for the reasons that follow:

•

damaged or corroded float (float failure),

•

liquid density that does not correspond to the specifications received with the order and

•

draining the measuring chamber

For more data, refer to Errors

Errors on page 37.

ErrorsErrors

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3 INSTALLATION

3.8 Electromagnetic compatibility

The design of the device agrees with European Standard EN 61326-1 and Immunity and Emissions requirements for industrial environments.

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4.1 Optional analog transmitter

• Remove the terminal compartment cover.

• Connect the device to the electrical circuit. Obey the national electrical codes.

ELECTRICAL CONNECTIONS 4

Figure 4-1: Electrical schematic for the 4...20 mA output module

1 Power supply terminals 2 Internal wiring - brown wire 3 Internal wiring - red wire 4 Optional LCD indicator 5 Power supply (+) - if optional LCD connected - red wire 6 Power supply (-) - if optional LCD connected - black wire 7 LCD power supply terminal (10...35 VDC)

Figure 4-2: Electrical schematic for the 4...20 mA + HART output module

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4 ELECTRICAL CONNECTIONS

Figure 4-3: Electrical schematic for the FOUNDATION™ Fieldbus / PROFIBUS PA module

1 Bus connection terminals 2 Segment coupler 3 Bus termination 4 Internal wiring - orange wire 5 Internal wiring - brown wire

BM 26 BASIC/ADVANCED

For more electrical data, refer to

Technical data: optional analog transmitter

on page 51.

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4.2 Optional limit switches

Figure 4-4: Terminal compartment

1 Terminal compartment cover 2 Bistable reed switch 3 Output terminal

• Remove the terminal compartment cover.

• Connect the device to the electrical circuit. Obey the national electrical codes.

ELECTRICAL CONNECTIONS 4

1 2 3

WARNING!

If the switch is set to LOW limit

LOW limit, make sure that switch is open

LOW limitLOW limit position. If the switch is set to HIGH limit

HIGH limit, make sure that switch is open

HIGH limitHIGH limit position.

Figure 4-5: Electrical schema

1 Non-NAMUR version 2 NAMUR version

For more electrical data, refer to

open when the float is below the switch

openopen

open when the float is above the switch

openopen

Technical data: optional limit switches

on page 56.

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