All rights reserved. It is prohibited to reproduce this documentation, or any part thereof, without
the prior written authorisation of KROHNE Messtechnik GmbH.
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H250 M40
1.1 Intended use
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!
This device is a Group 1, Class A device as specified within CISPR11:2009. It is intended for use in
industrial environment. There may be potential difficulties in ensuring electromagnetic
compatibility in other environments, due to conducted as well as radiated disturbances.
INFORMATION!
The manufacturer is not liable for any damage resulting from improper use or use for other than
the intended purpose.
The variable area flowmeters are suitable for measuring clean gases, vapours and liquids.
Intended use:
• The product may not contain any ferromagnetic particles or solids. It may be necessary to
install magnetic filters or mechanical filters.
• The product must be sufficiently liquid and free of deposits.
• Avoid pressure surges and pulsing flows.
• Open valves slowly. Do not use solenoid valves.
SAFETY INSTRUCTIONS
1
Use suitable measures to eliminate compression vibrations during gas
measurements:
• Short pipeline lengths to next restriction
• Nominal pipe size not greater than nominal device size
• Use of floats with damping
• Increase in operating pressure (while taking into account the resulting change in density and
thus change in scale)
Observe installation conditions according to VDI/VDE 3513-3.
DANGER!
For devices used in hazardous areas, additional safety notes apply; please refer to the Ex
documentation.
CAUTION!
Do not use any abrasive media containing solid particles or highly viscous media.
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SAFETY INSTRUCTIONS
1.2 Certifications
CE marking
The device fulfils all applicable statutory requirements of the EU directives:
• Pressure equipment directive
• For devices with electrical installations: EMC directive
• Devices for use in hazardous areas: ATEX directive
as well as
• NAMUR recommendations NE 21, NE 43 and NE 107
The manufacturer certifies successful testing of the product by applying the CE marking.
An EU declaration of conformity regarding the directives in question and the associated
harmonised standards can be downloaded from our internet site.
H250 M40
1.3 Pressure equipment directive
A conformity assessment in accordance with pressure equipment directive has been carried out
for the devices described. Conformity is certified by applying the CE mark. The number of the
notified body is also stated.
The PED key describes the rating of the devices:
Example: PED/G1/III/H
GGases and vapours
1Fluid group 1
IIICategory III
HConformity assessment method according to Module H
The PED key identification can be found on the nameplate of the device (for details refer to
Nameplate
INFORMATION!
The stated pressures (PS) and temperatures (TS) only apply as refers to the pressure resistance
of the sensor body. As regards the functionality of the entire device, further restrictions of the
maximum temperature may need to be observed (e.g. ATEX approval). Devices rated below
category I due to their size, do not receive the CE mark in the scope of the PED. These devices
are subject to applicable sound engineering practice (SEP).
on page 16).
6
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H250 M40
SAFETY INSTRUCTIONS
1
Residual risk
A risk analysis in accordance with the pressure equipment directive has been carried out for the
devices . The residual risk is described as follows:
• The devices are designed according to the valid and applicable rules and standards for static
operation and their pressure resistance is calculated for the declared maximum pressure
and temperature (no calculation for cyclical change).
• Responsibility for the use of the measuring devices with regard to corrosion resistance of the
used materials against the measured fluid lies solely with the operator.
• Avoid abrasion.
• Avoid pulsation and cavitation.
• Protect devices from vibration and high-frequency oscillation.
• Draining (backflow) may be delayed due to the float in the measuring tube.
• Implement appropriate measures to counteract external fire hazards
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SAFETY INSTRUCTIONS
1.4 Safety instructions from the manufacturer
1.4.1 Copyright and data protection
The contents of this document have been created with great care. Nevertheless, we provide no
guarantee that the contents are correct, complete or up-to-date.
The contents and works in this document are subject to copyright. Contributions from third
parties are identified as such. Reproduction, processing, dissemination and any type of use
beyond what is permitted under copyright requires written authorisation from the respective
author and/or the manufacturer.
The manufacturer tries always to observe the copyrights of others, and to draw on works created
in-house or works in the public domain.
The collection of personal data (such as names, street addresses or e-mail addresses) in the
manufacturer's documents is always on a voluntary basis whenever possible. Whenever
feasible, it is always possible to make use of the offerings and services without providing any
personal data.
H250 M40
We draw your attention to the fact that data transmission over the Internet (e.g. when
communicating by e-mail) may involve gaps in security. It is not possible to protect such data
completely against access by third parties.
We hereby expressly prohibit the use of the contact data published as part of our duty to publish
an imprint for the purpose of sending us any advertising or informational materials that we have
not expressly requested.
1.4.2 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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H250 M40
1.4.3 Product liability and warranty
The operator shall bear responsibility for the suitability of the device for the specific purpose.
The manufacturer accepts no liability for the consequences of misuse by the operator. Improper
installation or operation of the devices (systems) will cause the warranty to be void. The
respective "Standard Terms and Conditions" which form the basis for the sales contract shall
also apply.
1.4.4 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.
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 icons as shown below.
SAFETY INSTRUCTIONS
1
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SAFETY INSTRUCTIONS
1.4.5 Warnings and symbols used
Safety warnings are indicated by the following symbols.
DANGER!
This warning 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.
H250 M40
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.
iRESULT
RESULT
RESULTRESULT
This symbol refers to all important consequences of the previous actions.
1.5 Safety instructions for the operator
10
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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H250 M40
2.1 Scope of delivery
INFORMATION!
Inspect the packaging carefully for damages or signs of rough handling. Report damage to the
carrier and to the local office of the manufacturer.
INFORMATION!
Do a check of the packing list to make sure that you have all the elements given in the order.
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.
DEVICE DESCRIPTION
2
Figure 2-1: Scope of delivery
1 Measuring device in ordered version
2 For the ESK4-T version - bar magnet
3 Documentation
4 Certificates, calibration report (supplied to order only)
5 Wrench
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DEVICE DESCRIPTION
2.2 Device version
• H250 with indicator M40
• H250 with M40 indicator with display cut-out for ESK4-T
Figure 2-2: Device version - H250 with M40 indicator
Description of the device version
1. H250/RR/M40
• Local indicator without auxiliary power
• Max. 2 limit switches, type NAMUR, NAMUR safety-oriented or transistor (3-wire)
• Electrical signal output 4...20 mA, HART
• Intrinsically safe (Ex i) or in explosion-proof enclosure (Ex d)
®
or Fieldbus communication
H250 M40
2. H250/RR/M40
• Additional LCD, measured value and/or flow counter
• 2 configurable binary outputs, limit value or pulse output
1 Basic module with electronic magnet sensors ESK4 / ESK4A
2 Connection bus module
3 DIP switch for bus settings
For more details refer to the supplementary instructions "H250 M40 Foundation Fieldbus" or
"H250 M40 Profibus PA".
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H250 M40
2.2.2 Float damping
Float damping is characterised by high standstill times and self-centering. The damping sleeve
is made of high performance ceramic or PEEK, depending on the medium and the application.
Float damping can also be retrofitted for the user (refer to "Service").
Use of damping
• Generally when CIV and DIV floats are used for gas measurement.
• For TIV floats (H250/RR and H250/HC only) with an operating primary pressure:
Nominal size according toOperating primary pressure
2
2.2.3 Pointer damping
In principle, the indicating element with its magnetic system contains indicator damping. An
additional eddy current brake is advantageous in the event of fluctuating or pulsing flows. The
magnets on the eddy current brake surround the pointer vane without touching it, damping its
movement. The result is a much steadier pointer position, without distorting the measured
value. The eddy current brake can be retrofitted during operation without recalibration. Note the
maximum tightening torque (0.12 Nm) for the turnbuckle!
Figure 2-7: Pointer damping
1 Eddy current brake
2 Pointer vane
3 Support
4 Pointer cylinder
5 Turnbuckle, max. tightening torque is 0.12 Nm
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2
DEVICE DESCRIPTION
2.3 Nameplate
INFORMATION!
Check on the device nameplates, that the device is supplied according to your order.
H250/.././M40/..-Ex
P/A: 011123456.001
PED/G1/II/H
PTmax: xxx bar
Tag-No.:
PTB 11 ATEX 2012 X
II2G Ex ia IIC T6
IECEx PTB 11.0069 X
amb
: -20°C... +60°C (T6: +40°C)
T
Ui = xxV Ii = xxmA Pi = xW
ESK...
Ci = xxnF Li = xuH
Ui = xxV Ii = xxmA Pi = xW
Kmin1
Ci = xxnF Li = xuH
Ui = xxV Ii = xxmA Pi = xW
Kmin2
Ci = xxnF Li = xuH
MD:201x
PS: xxx bar
TS: xx °C
0035
0102
H250 M40
www.krohne.com
Figure 2-8: Example of a nameplate
1 Device type
2 Manufacturer
3 Notified body
4 Rating data: temperature & pressure rating
5 PED data
6 Ex data
7 Electrical connection data
8 Internet site
Additional markings on the indicator
• SN - serial number
• SO - sales order / item
• PA - production order
• Vx - product configurator code
• AC - article code
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H250 M40
2.4 Description code
The description code consists of the following elements *:
Figure 2-9: Description code
1 Device type
Device type
Device typeDevice type
H250 - standard version
H250H - horizontal flow direction
H250U - flow direction from top to bottom
2 Materials / versions
Materials / versions
Materials / versionsMaterials / versions
RR - stainless steel
C - PTFE or PTFE/ceramics
HC - Hastelloy
Ti - Titanium
Mo - Monel
In - Inconel
F - aseptic version (food)
3 Heating jacket version
Heating jacket version
Heating jacket versionHeating jacket version
B - with heating jacket
4 Type series of indicators
Type series of indicators
Type series of indicatorsType series of indicators
M40 - Indicator M40
M40R - indicator in stainless steel housing
5 High-temperature version
High-temperature version
High-temperature versionHigh-temperature version
HT - version with HT extension
6 Electrical signal output
Electrical signal output
Electrical signal outputElectrical signal output
ESK - electrical signal output 4...20 mA (ESK4 / ESK4A)
- optionally available with counter, I/O module and display (ESK4-T)
- Foundation Fieldbus (ESK4-FF)
- Profibus PA (ESK4-PA)
7 Limit switches
Limit switches
Limit switchesLimit switches
K1 - one limit switch
K2 - two limit switches
8 Explosion protection
Explosion protection
Explosion protectionExplosion protection
Ex - Explosion-protected equipment
9 SIL version
SIL version
SIL versionSIL version
SE - SIL compliant electronic signal output
SK - SIL compliant limit switch
®
DEVICE DESCRIPTION
2
* positions which are not needed are omitted (no blank positions)
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2
DEVICE DESCRIPTION
2.5 Electronic revision
The electronic revision (sticker on the base module ESK4 / ESK4A) indicates the respective
hardware/software status of the electronics. All add-on modules (ESK4-T, ESK4-FF and ESK4PA) have an additional sticker indicating their respective firmware version.
Electronic revisionExplanations
H250 M40
ER 1.1.xBasic version (cannot be combined with other indicator versions):
ESK4 / current output 4…20 mA with HART
(ESK4 HART DD 01.01. AMS10x AMS11x
ESK4 HART DD 01.01. PDM6.0
ESK4 HART DTM 1.0.3 FDT1.2)
ER 2.0.xFunctional add-on to ER 1.1.x:
ER 2.1.xFunctional add-on to ER 2.0.x:
ER 2.2.xFunctional add-on to ER 2.1.x:
ER 3.0.xFunctional add-on:
Table 2-1: Electronic revision
can be combined with indicator version ESK4 FF / Foundation Fieldbus;
(Firmware version FF module from 1.0.2)
can be combined with indicator version ESK4-PA / Profibus PA
(Firmware version PA module from 1.0.0)
can be combined with indicator version ESK4-T / LCD, binary inputs/outputs
(Firmware version T module from 1.1.0)
Support of failure signal (low) according to NE 43
for the ESK4 current output module
®
Update for HART
can be combined with ESK4-FF (Firmware version FF module from 1.0.2)
Firmware Version ESK4-PA (... PA module from 1.0.0)
Firmware Version ESK4-T (... T module from 1.2.0)
communication from 5.9 to 7.4 including new DD/DTM
®
communication
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H250 M40
3.1 General installation notes
INFORMATION!
Inspect the packaging carefully for damages or signs of rough handling. Report damage to the
carrier and to the local office of the manufacturer.
INFORMATION!
Do a check of the packing list to make sure that you have all the elements given in the order.
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.
3.2 Storage
• Store the device in a dry, dust-free location.
• Avoid direct exposure to the sun.
• Store the measuring device in the original packaging.
• The permissible storage temperatures for standard devices are: -40...+80°C / -40...+176°F
INSTALLATION
3
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3
INSTALLATION
3.3 Installation conditions
CAUTION!
When installing the device in the piping, the following points must be observed:
•
The variable area flowmeter must be installed vertically (measuring principle). Flow direction
from bottom to top. For installation recommendations please refer also to directive
VDI/VDE 3513, sheet 3.
H250Hs are installed horizontally and H250U devices are installed vertically with the flow
direction from top to bottom.
•
A straight unimpeded inlet run of ≥ 5 DN upstream of the device and a straight outlet run of
≥ 3 DN downstream of the device are recommended.
•
Screws, bolts and gaskets are to be provided by the customer and must be selected in
accordance with the pressure rating of the connection or the operating pressure.
•
The inner diameter of the flange deviates from the standard dimensions. Flange seal
standard DIN 2690 or ASME B16.21 can be applied.
•
Align the gaskets. Tighten the nuts with the tightening torques of the appropriate pressure
rating.
For devices with PTFE liner or ceramic liner and PTFE raised faces, refer to chapter
"Tightening torques".
•
Control devices are to be positioned downstream of the measuring device.
•
Shutoff devices are preferably to be positioned upstream of the measuring device.
•
Before connecting, blow or flush out the pipes leading to the device.
•
Piping for gas flow need to be dried before the device is installed.
•
Use connectors suitable for the particular device version.
•
Align the piping centrically with the connection bores on the measuring device so they are
free of stresses.
•
If necessary, the piping has to be supported to reduce the vibrations transmitted to the
measuring device.
•
Do not lay signal cables directly next to cables for the power supply.
H250 M40
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H250 M40
INSTALLATION
3
Minimum distance between devices
When several devices are installed next to each other, a minimum distance of > 300 mm / 11.8"
between the devices is necessary.
Figure 3-1: Minimum distance between devices
Take special note of the installation position for the H250H with horizontal flow
direction:
Figure 3-2: Installation position for H250H
In order to comply with thermal parameters and measuring accuracy, H250H flowmeters for
horizontal installation are to be installed in the pipeline so that the display is located on the side
of the measuring tube. The maximum product and ambient temperatures indicated as well as
the measuring accuracy are based on lateral installation of the indicator.
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3
INSTALLATION
3.3.1 Tightening torques
For devices with PTFE liner or ceramic liner and PTFE raised face, tighten the flange threads
with the following torques:
Nominal size according toStud boltsMax. torque
EN 1092-1ASME B16.5ENASMEEN 1092-1ASME 150 lb
DNPNInchlb150 lb300 lbNmft*lbfNmft*lbf
15401/2"150/3004x M124x 1/2"4x 1/2"9.87.15.23.8
25401"150/3004x M124x 1/2"4x 5/8"2115107.2
50402"150/3004x M164x 5/8"8x 5/8"57414130
80163"150/3008x M164x 5/8"8x 3/4"47347051
100164"150/3008x M168x 5/8"8x 3/4"67485036
Table 3-1: Tightening torques
3.3.2 Magnetic filters
H250 M40
The use of magnetic filters is recommended when the medium contains particles which can be
influenced magnetically. The magnetic filter is to be installed in the flow direction upstream of
the flowmeter. Bar magnets are positioned helically in the filter to provide optimal efficiency at
low pressure loss. All of the magnets are coated individually with PTFE to protect against
corrosion. Material: 1.4404 / 316L
Figure 3-3: Types of magnetic filters
1 Type F - fitting part with flange - overall length 100 mm / 4"
2 Type FS - fitting part without flange - overall length 50 mm / 2"
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H250 M40
3.3.3 Heat insulation
CAUTION!
The indicator housing may not be heat-insulated.
The heat insulation 3 may only reach as far as the housing fastening 4.
Figure 3-4: Heat insulation
1 Standard indicator M40
2 Indicator with HT extension
INSTALLATION
3
CAUTION!
The heat insulation 1 may only reach to the rear of the housing 2. The area around the cable
entries 3 must be freely accessible.
Figure 3-5: Heat insulation - cross-section
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ELECTRICAL CONNECTIONS
4.1 Safety instructions
DANGER!
All work on the electrical connections may only be carried out with the power disconnected. Take
note of the voltage data on the nameplate!
DANGER!
Observe the national regulations for electrical installations!
DANGER!
For devices used in hazardous areas, additional safety notes apply; please refer to the Ex
documentation.
WARNING!
Observe without fail the local occupational health and safety regulations. Any work done on the
electrical components of the measuring device may only be carried out by properly trained
specialists.
H250 M40
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.
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H250 M40
ELECTRICAL CONNECTIONS
4.2 Electrical connection for indicator M40
4.2.1 Connection of the limit switches K1/K2
The M40 indicator can be fitted with a maximum of two limit switches.
The limit switch operates as a proximity switch which is activated inductively by the semicircular
metal vane of the pointer. The switching points are set using the contact pointers.
The position of the contact pointers is indicated on the scale.
4
Figure 4-1: Design of limit switch module
1 MIN contact
2 MAX contact
3 Locking screw
4 Peak value
5 Connection terminal
The connection terminals have a pluggable design and can be removed to connect the cables.
The built-in limit switch types are shown on the nameplate of the indicator.
ContactMINMAX
Terminal number123456
Connection 2-wire NAMUR-+-+
Connection 3-wire+-+-
Connection Reed SPST+-+-
Table 4-1: Electrical connection of the limit switches
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4
ELECTRICAL CONNECTIONS
Connection diagram for the limit switches
Figure 4-2: Connection terminals for limit switches
1 Limit switch 2-wire NAMUR
2 Limit switch 3-wire
3 Limit switch Reed SPST
4 Terminal connection of Min. contact
5 Terminal connection of Max. contact
6 3-wire load
7 NAMUR isolated switching amplifier
8 3-wire power supply
H250 M40
Limit setting
Figure 4-3: Limit setting
1 Contact pointer MAX
2 Contact pointer MIN
3 Locking screw (max. tightening torque is 0.2 Nm)
4 Scale support
Setting is carried out directly via contact pointers 1 and 2:
• Pull the upper scale support 2 mm / 0.08" flexibly upwards and pull out the scale from its
locking point to the side.
• Loosen the locking screw 3 slightly.
• Slide in the scale up to the locking point.
• Set contact pointers 1 and 2 to the desired switching point.
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H250 M40
ELECTRICAL CONNECTIONS
4
After the setting:
• Pull the upper scale support 2 mm / 0.08" flexibly upwards and pull out the scale again from
its locking point to the side.
• Tighten the locking screw 3 with max. 0.2 Nm.
• Slide in the scale up to the locking point.
CAUTION!
If the maximum torque (0.2 Nm) is exceeded, the locking screw can be torn off during tightening!
Definition of switch contact
Figure 4-4: Definition of switch contact
1 MIN contact
2 MAX contact
3 Pointer vane with switching vane
If the pointer vane goes into the slot, an alarm is triggered.
If the pointer vane is outside of the proximity switch, a wire break in a NAMUR contact also
triggers the alarm.
The 3-wire limit switch does not have any wire break detection.
Figure 4-5: Definition MIN-MIN - MAX-MAX
1 MIN 2 contact or MAX 1 contact
2 MIN 1 contact or MAX 2 contact
ContactTypeCurrent consumption
MIN 1NAMUR≤ 1mA
MIN 2NAMUR≤ 1mA
MAX 1NAMUR≥ 3mA
MAX 2NAMUR≥ 3mA
Table 4-2: Current consumption in the position shown:
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4
ELECTRICAL CONNECTIONS
4.2.2 Current output ESK4 / ESK4A
The connecting terminals of the ESK4 / ESK4A have a pluggable design and can be removed in
order to connect the cables.
Figure 4-6: ESK4 / ESK4A connection
1 Current output of ESK4 / ESK4A
2 Power supply 14...30 VDC
3 Measuring signal 4...20 mA
4 External load, HART
®
communication
H250 M40
Power supply M40 with galvanic isolation
Wiring must be planned with great care when it comes to connecting other devices such as
evaluation units or process control. Internal connections in these devices (e.g. GND with PE,
mass loops) may lead to non-permitted voltage potentials which could negatively affect the
function of the converter itself or that of a device connected to it. In such cases a protected extralow voltage (PELV) is recommended.
Figure 4-7: Power supply M40 with galvanic isolation
1 Terminal connection
2 Converter supply isolator with galvanic isolation
3 Power supply (refer to isolator information)
4 Measuring signal 4...20 mA
5 External load, HART
®
communication
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