KROHNE H250 M40 Series Wiring diagram

Equipment protection level Gc
in protection type "increased safety" Ex ec
H250 M40
H250 M40H250 M40
H250 M40 Supplementary Instructions
Supplementary InstructionsSupplementary Instructions
Supplementary Instructions
© KROHNE 11/2019 - 4007945001 - AD H250-M40 Exec Gc R01 en

CONTENTS
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H250 M40
1 Safety instructions 3
1.1 General notes ................................................................................................................... 3
1.2 EU conformity ................................................................................................................... 3
1.3 Approval according to the IECEx scheme ........................................................................ 3
1.4 Safety instructions............................................................................................................ 4
2 Device description 5
2.1 Device description ............................................................................................................ 5
2.2 Description code............................................................................................................... 5
2.3 Marking............................................................................................................................. 6
2.4 Flammable products ........................................................................................................ 7
2.5 Equipment protection level .............................................................................................. 8
2.6 Types of protection ........................................................................................................... 8
2.7 Ambient temperature / temperature classes.................................................................. 9
2.8 Electrical data................................................................................................................. 15
3 Installation 16
3.1 Mounting ......................................................................................................................... 16
3.2 Special conditions........................................................................................................... 17
4 Electrical connections 18
4.1 General notes ................................................................................................................. 18
4.2 Power supply .................................................................................................................. 18
4.3 Inputs / outputs .............................................................................................................. 18
4.4 Grounding and equipotential bonding............................................................................ 19
5 Operation 20
5.1 Start-up........................................................................................................................... 20
5.2 Operation ........................................................................................................................ 20
5.3 Electrostatic charge .......................................................................................................20
6 Service 21
6.1 Maintenance ................................................................................................................... 21
6.2 Dismantling .................................................................................................................... 21
7 Notes 22

SAFETY INSTRUCTIONS 1
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1.1 General notes
This additional instruction applies to explosion-protected versions of variable area flowmeters
with electrical built-ins with protection type increased safety "e", equipment protection level
(EPL) Gc.
It completes the standard manual for the non explosion-protected versions.
The information given in this instruction contains only the data relevant to explosion protection.
The technical details given in the manual for the non explosion-protected versions remain
unchanged unless they will be excluded or replaced by this supplementary instruction.
1.2 EU conformity
The manufacturer declares with the EU declaration of conformity, in which the applied standard
(EN IEC 60079-0:2018 and EN 60079-7:2015) is also specified, on his own responsibility
conformity with the protection goals of directive 2014/34/EU (ATEX) for use in hazardous areas
with gas.
The EU declaration of conformity for the equipment category II 3 G is based on the EC type
examination certificate of the Physikalisch Technische Bundesanstalt (PTB):
The "X" after the certificate number refers to special conditions for safe use of the device, which
have been listed in these instructions.
If needed the EU type examination certificate can be downloaded from the manufacturer's
website.
1.3 Approval according to the IECEx scheme
Conformity of the variable area flowmeter for use in hazardous areas with gas was tested in
accordance with the "IECEx Certification Scheme for Explosive Atmospheres" according to
IEC 60079-0:2017 and IEC 60079-7:2015.
The number of the IEC certificate is:
The "X" after the certificate number refers to special conditions for safe use of the device, which
have been listed in these instructions.
If needed, the IEC certificate can be downloaded from the manufacturer's website.
PTB 11 ATEX 2012 X
PTB 11 ATEX 2012 XPTB 11 ATEX 2012 X
PTB 11 ATEX 2012 X
IECEx PTB 11. 0069 X
IECEx PTB 11. 0069 XIECEx PTB 11. 0069 X
IECEx PTB 11. 0069 X

1 SAFETY INSTRUCTIONS
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1.4 Safety instructions
If these instructions are not followed, there is a risk of explosion.
Assembly, installation, start-up and maintenance may only be performed by personnel trained in
explosion protection!
CAUTION!
The operator or his agent is responsible for observing any additional standards, directives or
laws if required due to operating conditions or place of installation.
This applies in particular to the use of easily detachable process connections when measuring
flammable media.
CAUTION!
When an equipment fault is detected the device shall be de-energised and send back to the
manufacturer for repair.

DEVICE DESCRIPTION 2
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2.1 Device description
Variable area flowmeters measure and display the volume flow of flammable and non-
flammable gases and liquids. Depending on the device version, electrical limit switch contacts
and a 4...20 mA signal output with HART
®
communication, a Foundation Fieldbus interface or a
Profibus PA interface can be installed in the indication unit.
2.2 Description code
The safety description code consists of the following elements *:
* positions which are not needed are omitted (no blank positions)
Figure 2-1: Safety description code
1 Type series of measuring unit H250
Type series of measuring unit H250Type series of measuring unit H250
Type series of measuring unit H250
H250 - standard version, vertical upwards
H250H - horizontal orientation
H250U - vertical downwards
2 Measuring unit materials / versions
Measuring unit materials / versionsMeasuring unit materials / versions
Measuring unit materials / versions
RR - stainless steel
C - PTFE or PTFE/ceramics
HC - Hastelloy C
Ti - Titanium
F - Food
3 Heating jacket version
Heating jacket versionHeating jacket version
Heating jacket version
blank - without heating jacket
B - with heating jacket
4 Signal converter version
Signal converter versionSignal converter version
Signal converter version
M40 - aluminium housing, painted (standard)
M40S - aluminium housing with increased corrosion protection
M40R - stainless steel housing
5 High-temperature version
High-temperature versionHigh-temperature version
High-temperature version
blank - without HT extension
HT - with HT extension
6 Electrical signal output
Electrical signal outputElectrical signal output
Electrical signal output
blank - without transmitter
ESK - electrical signal output 4...20 mA (ESK4)
. . . - optionally available with counter, I/O module and display (ESK4-T) or
. . . - Foundation Fieldbus (ESK4-FF) or
. . . - Profibus PA (ESK4-PA)
7 Limit switch
Limit switchLimit switch
Limit switch
blank - without limit switches
K1 - one limit switch
K2 - two limit switches
R1 - 1 Reed switch
R2 - 2 Reed switches
8 Version
VersionVersion
Version
Ex - explosion-protected version
9 SIL version
SIL versionSIL version
SIL version
SE - SIL compliant electronic signal output
SK - SIL compliant limit switch

2 DEVICE DESCRIPTION
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2.3 Marking
The marking of the entire device is on the indication unit, where the following identification
plates can be found (refer also to designation code).
Additional markings on the housing cover:
•SN - serial number
•SO - sales order / item
•PA - order
•Vxxx - product configurator code
•AC - article code
Additional plate
The association of the housing cover to the device is confirmed by an additional plate with the
serial number on the interior of the indicator part.
Figure 2-2: Example of a nameplate
1 Device type
2 Device version
3 Identification number of the notified body ATEX & PED
4 Rating data: temperature & pressure rating
5 Data according to the pressure equipment directive
6 Marking according to the notified body
7 Electrical connection data
8 Note to observe the documentation and for disposal
9 Data matrix

DEVICE DESCRIPTION 2
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2.4 Flammable products
Atmospheric conditions:
Atmospheric conditions:Atmospheric conditions:
Atmospheric conditions:
The standard atmospheric conditions under which it may be assumed that Ex equipment can be
operated are:
•Temperature: -20...+60°C / -4...+140°F
•Pressure: 80...110 kPa (0.8...1.1 bar) / 11.6...15.9 psi
•Air with normal oxygen content, typically 21%v/v
Ex equipment operating outside the standard temperature range must be tested and certified
(e.g. for ambient temperature range -40...+65°C / -40...+149°F).
Ex equipment operating outside the standard atmospheric pressure range and standard oxygen
content is not permitted.
Operating conditions:
Operating conditions:Operating conditions:
Operating conditions:
The measuring unit of variable area flowmeters operate outside the standard atmospheric
pressure range, which means that explosion protection, regardless of the zone assignment, is
fundamentally not applicable for the measuring unit (piping).
WARNING!
Operation with flammable products is only permitted as long as no explosive fuel/air mixture
builds up inside of the piping at the same time the atmospheric conditions are exceeded.
The operator is responsible to ensure that the flowmeter is operated safely in terms of the
temperature and pressure of the products used. In case of operation with flammable products
the measuring units must be included in the periodic pressure tests of the piping.
When using the device version H250/C... (PTFE version, non-conductive) the minimum
conductivity of the media must be 10
-8
S/m, in order to avoid danger from electrostatic charge.

2 DEVICE DESCRIPTION
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2.5 Equipment protection level
Variable area flowmeters are designed according to IEC 60079-0 and IEC 60079-7 in
equipment protection level (EPL) Gc for use in zone 2.
The inside of the measuring unit is also approved for zone 2.
2.6 Types of protection
The variable area flowmeter is designed with protection type "Increased safety" according to
IEC 60079-7. Explosion protection is ensured in that there are no contacts or hot surfaces with a
sparking effect during operation.
The identification for equipment category II 3 G or the equipment protection level (EPL) Gc is:
II 3G
II 3GII 3G
II 3G (ATEX only)
Ex ec IIC T6...T2 Gc
Ex ec IIC T6...T2 GcEx ec IIC T6...T2 Gc
Ex ec IIC T6...T2 Gc
The marking contains the following information:
INFORMATION!
Definition of zone 2:
This is an area in which an explosive atmosphere as a result of the mixture of flammable
substances in the form of gas, steam or mist with air is not expected to occur under normal
operation. If, however, such an atmosphere does occur it only lasts for a brief period of time.
II
IIII
II Explosion protection, group II
3
33
3Equipment category 3
G
GG
GGas explosion protection
Ex ec
Ex ecEx ec
Ex ec Explosion protection through increased safety, protection level "ec"
IIC
IICIIC
IIC Gas group, suitable for gas groups IIC, IIB and IIA
T6...T2
T6...T2T6...T2
T6...T2 Temperature class range, suitable for temperature classes T6...T1
Gc
GcGc
Gc EPL, suitable for zone 2
Table 2-1: Description of the marking
INFORMATION!
The temperature class of the device depends on the product temperature.

DEVICE DESCRIPTION 2
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2.7 Ambient temperature / temperature classes
Due to the influence of the product temperature, variable area flowmeters with built-in electrical
equipment (electric variants) are not assigned to any fixed temperature class. The temperature
class of these devices is rather a function of the product temperature and ambient temperature
that is present and the specific device version. The classification is outlined in the following
tables.
The tables take into account the following parameters:
•built-in equipment
•Ambient temperature T
amb
•Product temperature T
m
•Nominal size DN
•Standard or high temperature version (HT)
•Standard or heating jacket version
•Heat resistance of the connecting cable
When using more than one built-in equipment, the data of the most unfavourable equipment
should be used.
For certain device versions, lower values apply due to differing boundary conditions (e.g. liner
materials). In this regard, pay special attention to the pressure and temperature indications on
the device nameplate.
INFORMATION!
The maximum permissible product temperatures listed in the tables are valid under
the following conditions:
• The measuring device is installed and operated in accordance with the manufacturer's
installation instructions.
• It must be ensured that the measuring device is not heated by the effects of additional heat
radiation (sunshine, adjacent plant parts) and thus operated above the permissible ambient
temperature range.
• Insulation must be limited to the piping.
Unobstructed ventilation of the indicator part must be ensured.
For this purpose, the variant with a projecting indicator (HT version) is preferable.
• For device versions with a heating jacket the temperature of the heating medium does not
exceed the maximum permissible product temperature.

2 DEVICE DESCRIPTION
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Using a heat-resistant connecting cable
•HT version - high-temperature version with projecting indicator
•The permitted ambient temperature range is indicated on the nameplate; depending on the
device version it is
T
amb
= -40...+65°C / -40...+149°F or T
amb
= -25...+65°C / -13...+149°F.
•The minimum product temperature is -40°C/-40°F.
Lower product temperatures are possible, provided they do not fall below the permitted
temperature of the indicator (see reference point observation).
Heating jacket T
m
1
without with HT version T
amb
≤40 T
amb
≤60 T
amb
≤65
DN15, DN25, DN50 DN15, DN25 220 105 75
x - 175 95
DN80, DN100 DN50, DN80 165 90 75
x - 155 90
Table 2-2: Temperature table in °C
1Maximum value of the product temperature for the use of a standard connecting cable. For higher product
temperatures a connecting cable with a temperature resistance of 90°C is required.
Heating jacket T
m
1
without with HT version T
amb
≤104 T
amb
≤140 T
amb
≤149
DN15, DN25, DN50 DN15, DN25 428 221 167
x - 347 203
DN80, DN100 DN50, DN80 329 194 167
x - 311 194
Table 2-3: Temperature table in °F
1Maximum value of the product temperature for the use of a standard connecting cable. For higher product
temperatures a connecting cable with a temperature resistance of 194°F is required.