KROHNE VA40 Wiring diagram

Variable area flowmeter
Equipment protection level Gb
in protection type intrinsic safety "i"
VA40
VA40VA40
VA40 Supplementary Instructions
Supplementary InstructionsSupplementary Instructions
Supplementary Instructions
© KROHNE 10/2020 - 4002262403 - AD VA40 Exia Gb R04 en

CONTENTS
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VA40
1 Safety instructions 3
1.1 General notes ................................................................................................................... 3
1.2 EU conformity ................................................................................................................... 3
1.3 Safety instructions............................................................................................................ 3
2 Device description 4
2.1 Description of device ........................................................................................................ 4
2.2 Description code............................................................................................................... 4
2.3 Marking............................................................................................................................. 5
2.4 Flammable products ........................................................................................................ 7
2.5 Equipment category .........................................................................................................7
2.6 Types of protection ........................................................................................................... 8
2.7 Ambient temperature / temperature classes.................................................................. 9
2.8 Electrical data................................................................................................................. 10
3 Installation 11
3.1 Mounting ......................................................................................................................... 11
3.2 Special conditions........................................................................................................... 12
4 Electrical connections 13
4.1 General notes ................................................................................................................. 13
4.2 Grounding and equipotential bonding............................................................................ 13
5 Operation 14
5.1 Start-up........................................................................................................................... 14
5.2 Operation ........................................................................................................................ 14
5.3 Electrostatic charge .......................................................................................................14
6 Service 16
6.1 Maintenance ................................................................................................................... 16
6.2 Dismantling .................................................................................................................... 16
7 Notes 17

SAFETY INSTRUCTIONS 1
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1.1 General notes
This additional instruction applies to explosion-protected versions of variable area flowmeter
with electrical built-ins with protection type intrinsic safety "i", equipment protection level (EPL)
Gb.
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 on his own responsibility
conformity with the protection goals of directive 2014/34/EU for use in hazardous areas with gas.
The EU type examination certificate of the Physikalisch Technische Bundesanstalt (PTB) forms
the basis of the EU declaration of conformity. Conformity with harmonised standards was
checked in accordance with EN IEC 60079-0:2018 and EN 60079-11:2012.
The "X" after the certificate number refers to special conditions for safe use of the device, which
have been listed in these instructions.
If necessary, the EU type examination certificate can be downloaded from the manufacturer's
website.
1.3 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
personnel trained inpersonnel trained in
personnel trained in
explosion protection
explosion protectionexplosion protection
explosion protection!
PTB 05 ATEX 2026 X
PTB 05 ATEX 2026 XPTB 05 ATEX 2026 X
PTB 05 ATEX 2026 X
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.

2 DEVICE DESCRIPTION
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2.1 Description of device
Variable area flowmeters measure and display the flow of flammable and non-flammable gases
and liquids. Up to two separately adjustable electrical limit switches can be mounted to the local
indication.
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 VA40
1 Connection type
Connection typeConnection type
Connection type
V - screw connection
S - tube socket
F - flange connection
A - aseptic connection, conforming to food standards
2 Material of connection
Material of connectionMaterial of connection
Material of connection
R - stainless steel 1.4404 (316 L)
ST - steel, electroplated and chromised
PV - plastic PVDF
3 Limit switches / signal output
Limit switches / signal outputLimit switches / signal output
Limit switches / signal output
K1 - one limit switch
K2 - two limit switches
Figure 2-2: Safety description code TG21
1 TG - immersion limit switch
2 21 - version 21
Figure 2-3: Safety description code MS14
1 MS - Magnetic switch
MS - Magnetic switchMS - Magnetic switch
MS - Magnetic switch
2 14 - Reed cartridge 14
14 - Reed cartridge 1414 - Reed cartridge 14
14 - Reed cartridge 14
3 Limit switch
Limit switchLimit switch
Limit switch
without - limit switch with cable tail
A - limit switch with connection box (standard)

DEVICE DESCRIPTION 2
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2.3 Marking
The marking of the complete device is shown in the following nameplate.
The variable area flowmeter is marked on the round housing.
Figure 2-4: Example of a nameplate
1 Device type
2 Manufacturer
3 Disposal symbol
4 Identification number of the notified body ATEX & PED
5 Note to observe the documentation, China RoHs and data matrix code
6 Marking according to the notified body
7 Serial number
8 Year of manufacture
9 PED data
Figure 2-5: Example of marking of limit switch TG21
1 Device type
2 Manufacturer
3 Electrical connection data
4 Built-in equipment
5 Note to observe the documentation, disposal and China RoHs

2 DEVICE DESCRIPTION
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No Ex marking for MS14 and MS14/A, because the Reed limit switch operates as a simple device
and complies to intrinsic safety EN 60079-11, paragraph 5.7.
Figure 2-6: Marking of limit switches MS14
1 Device type
2 Manufacturer
3 Ambient temperature
4 Internet site
5 Electrical connection data
6 Note to observe the documentation
Figure 2-7: Marking of limit switches MS14A
1 Type
2 Manufacturer
3 Ambient temperature
4 Internet site
5 Electrical connection data
6 Note to observe the documentation

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).
2.5 Equipment category
Variable area flowmeters are designed according to EN 60079-0 and EN 60079-11 in
equipment protection level (EPL) Gb for use in zone 1 and zone 2.
The inside of the measuring unit is also approved for zone 1.
WARNING!
Operation with flammable products is only permissible if no explosive fuel/air mixture is formed
in the piping when 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.
For additional information regarding electrostatics to be observed refer to Electrostatic charge
on page 14
.
INFORMATION!
Definition of zone 1:
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, under normal operation may occasionally occur.

2 DEVICE DESCRIPTION
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2.6 Types of protection
The variable area flowmeter is designed in type of protection "intrinsic safety", protection level
"ia" according to EN 60079-11.
The marking is: II 2G Ex ia IIC T6...T1 Gb
II 2G Ex ia IIC T6...T1 GbII 2G Ex ia IIC T6...T1 Gb
II 2G Ex ia IIC T6...T1 Gb
The marking contains the following information:
II
IIII
II Explosion protection, group II
2
22
2Equipment category 2
G
GG
GGas explosion protection
ia
iaia
ia Intrinsically safe, level of protection "ia"
IIC
IICIIC
IIC Suitable for gas groups IIC, IIB and IIA
T6...T1
T6...T1T6...T1
T6...T1 Temperature class range, suitable for temperature classes T6...T1
Gb
GbGb
Gb EPL, suitable for zone 1 or zone 2
Table 2-1: Description of the marking
INFORMATION!
The temperature class of the device depends on the product temperature.
INFORMATION!
For the equipment category II 2 G or EPL Gb, connection to an intrinsically safe circuit with
protection level "ib" is required.
When connecting the variable area flowmeter to an intrinsically safe circuit with protection level
"ia", a higher protection level is given.

DEVICE DESCRIPTION 2
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2.7 Ambient temperature / temperature classes
Due to the influence of the product temperature, no fixed temperature class is assigned to
variable area flowmeters. The temperature class of these devices is rather a function of the
present product temperature and ambient temperature. There is no distinction between devices
with one or two contacts. The classification is outlined in the following tables.
The tables take into account the following parameters:
•Maximum values P
i
•Ambient temperature T
amb
•Product temperature T
m
•Limit switch TG21 or MS14
Maximum permissible product and ambient temperatures for TG21
Maximum permissible product and ambient temperatures for MS14/.
The maximum product and ambient temperature is +85°C / +185°F.
These values may be limited by the information contained in the standard manual.
The maximum values listed in the manual must be taken into consideration.
Minimum product temperature for all versions
The minimum product temperature is -20°C/-4°F.
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 installation
instructions in the standard manual.
• It must be ensured that the flowmeter is not heated by the effects of additional heat radiation
(sunshine, neighboring system components) 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.
Supply Type 1 [ ≤34mW] Type 2 [ ≤64mW] Type 3 [ ≤169mW]
Temperature class T6 T5 T4...T1 T6 T5 T4...T1 T6 T5 T4...T1
Max. product temperature
[°C] 70 85 95 60 75 95 35 50 70
Max. product temperature
[°F] 158 185 203 140 167 203 95 122 158
Table 2-2: Max. permissible product and ambient temperatures TG21

2 DEVICE DESCRIPTION
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2.8 Electrical data
Limit switch TG21
The built-in intrinsically safe NAMUR limit switch TG21 may only be connected to isolation
switching amplifiers with separated intrinsically safe circuits to EN 60947-5-6 with the following
max. values:
When connecting to intrinsically safe circuits, take into consideration the following maximum
values per circuit for the energy stores.
Limit switch MS14
Built-in limit switch MS14 may only be connected to separate intrinsically safe circuits with the
following maximum values:
When connecting to intrinsically safe circuits, take into consideration the following maximum
values per circuit for the energy stores.
Supply P
i
[mW] U
i
[V] I
i
[mA]
Type 1 34 16 25
Type 2 64 16 25
Type 3 169 16 52
Table 2-3: Maximum values of the power supply units
C
i
[nF] L
i
[µH]
165 150
Table 2-4: Maximum values per circuit
P
i
[W] U
i
[V] I
i
[mA]
130 100
Table 2-5: Maximum values of the power supply units
C
i
[nF] L
i
[µH]
0 0
Table 2-6: Maximum values per circuit
WARNING!
Also, when operating the variable area flowmeter outside of the hazardous area, the connection
must be made to intrinsically safe circuits.
When connecting to non-intrinsically safe circuits, there is a risk of damage to the safety-
defining components.