KROHNE VAFLOW METERS User Manual
VA FLOWMETERS
VA FLOWMETERS
VA FLOWMETERSVA FLOWMETERS
Variable area flowmeters
without electrical built-ins
Equipment category II2G, II2D
Equipment category II2G, II2D
Equipment category II2G, II2DEquipment category II2G, II2D
Supplementary instructions
Supplementary instructions
Supplementary instructions Supplementary instructions
© KROHNE 11/2012 - 4000419904 MA VA Mech Ex AD R04 en
CONTENTS
VA FLOWMETERS
1 General notes 3
2 Safety instructions 4
2.1 Flammable products ........................................................................................................ 4
2.2 Device category ................................................................................................................ 4
2.3 Protection types................................................................................................................ 5
2.4 Surface temperature........................................................................................................5
2.5 Static electricity................................................................................................................ 6
2.5.1 Process dependent charging.................................................................................................. 6
2.5.2 Charging non-conductive external parts by cleaning ............................................................ 6
2.6 Device-specific notes ....................................................................................................... 7
3 Description 11
3.1 Description code............................................................................................................. 11
3.2 Marking........................................................................................................................... 11
4 Installation 13
4.1 Mounting and installation............................................................................................... 13
4.2 Special conditions........................................................................................................... 13
5 Operation 14
5.1 Initial start-up................................................................................................................. 14
5.2 Operation ........................................................................................................................ 14
6 Service 15
6.1 Maintenance ................................................................................................................... 15
6.2 Dismantling .................................................................................................................... 16
7 Notes 17
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VA FLOWMETERS
INFORMATION!
These additional operating instructions apply to explosion-protected, non-electrical versions of
variable area flowmeters.
•
DK32 DK34
•
DK37/M8M
•
H250/M8MG
•
H250/M9
•
H250/M40
•
DK46 DK47 DK48 DK800
•
GA24
•
VA40
in the categories
•
II2G
•
II2D
They complement the Installation and Operation Instructions for the non-explosion protected
versions. The information given in these Instructions contains only the data relevant to explosion
protection. The technical details given in the Installation and Operation Instructions for the nonexplosion protected versions apply unchanged unless excluded or superseded by these
Instructions. The series of the non-electrical versions of variable area flowmeters listed above
have been tested in accordance with
GENERAL NOTES 1
EN 13463-1:2009
EN 13463-1:2009
EN 13463-1:2009EN 13463-1:2009
EN 13463-5:2011
EN 13463-5:2011
EN 13463-5:2011EN 13463-5:2011
by the manufacturer.
The testing documentation has been stored in accordance with item 8, section 1b ii of the
directive 94/9/EG (ATEX) at the Physikalisch- Technischen Bundesanstalt (PTB), Braunschweig,
Germany under the registration number:
PTB 03 ATEX D127 X
PTB 03 ATEX D127 X
PTB 03 ATEX D127 XPTB 03 ATEX D127 X
.
The devices have identical designs in categories II2G and II2D.
Non-electrical devices for use
Non-electrical devices for use
Non-electrical devices for useNon-electrical devices for use
in hazardous areas
in hazardous areas
in hazardous areasin hazardous areas
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2 SAFETY INSTRUCTIONS
2.1 Flammable products
Atmospheric conditions:
Atmospheric conditions:
Atmospheric conditions:Atmospheric conditions:
An explosive atmosphere is a mixture of air and flammable gases, vapours, mists or dusts under
atmospheric conditions. The following values define it
= -20...+60°C / -4...+140°F and P
T
atm
Outside of this range, no key data are available as to ignition behaviour for most mixtures.
Installation condititions:
Installation condititions:
Installation condititions:Installation condititions:
Variable area flowmeters operate outside of atmospheric conditions, which means that
explosion protection according to Directive 94/9/EC (ATEX) – regardless of the zone assignment
– is fundamentally not applicable due to the lack of key safety data for the interior of the
measuring section.
WARNING!
Operation with flammable products is only permitted as long as no explosive fuel/air mixture
builds up on the inside of the flowmeter under operating conditions. The operator is responsible
for ensuring that the flowmeter is operated safely as regards 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 system. When using the device version H250/C...
(PTFE-liner, nonconductive) the min. conductivity of the medium must be 10
avoid the electrostatic charge.
= 0.8...1.1 bar.
atm
VA FLOWMETERS
-8
S/m, in order to
2.2 Device category
Variable area flowmeters are designed in Category II 2 G / II 2 D for use in zone 1 or zone 2 and
zone 21 or zone 22. The inside of the measuring unit is also approved for zone 1.
INFORMATION!
Definition of zone 1 acc. to EN 1127-1, Appendix B:
An area in which an explosive atmosphere may occasionally occur as a result of the mixture of
flammable substances in the form of gas, steam or mist with air under normal operation.
Definition of zone 21 acc. to EN 1127-1, Appendix B:
An area in which an explosive atmosphere may occasionally occur in the form of a cloud of
flammable dust in the air under normal operation.
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VA FLOWMETERS
2.3 Protection types
Non-electrical variable area flowmeters are designed in the protection class "design safety 'c'"
in accordance with EN 13463-5.
SAFETY INSTRUCTIONS 2
The marking is: II 2GD c IIC TX
The marking contains the following information:
The marking contains the following information:
The marking contains the following information:The marking contains the following information:
II
II Group II explosion protection
IIII
2222 Equipment category 2
GGGG Gas explosion protection
DDDD Dust explosion protection
cccc Protection through design safety
IIC
IIC Gas group, Suitable for gas groups IIC, IIB and IIA
IICIIC
TX
TX Surface temperature is determined by operating conditions
TXTX
II 2GD c IIC TX
II 2GD c IIC TXII 2GD c IIC TX
2.4 Surface temperature
It is to be assumed that a combustible fuel / air mixture can contact the outer wall of the
measuring tube and process connections. Any temperature gradient between the internal wall in
contact with the product (product temperature) and the outer surface is not taken into
consideration.
The actual maximum surface temperature does not depend on the device itself, but instead on
the operating conditions. The device itself does not generate heat and, for this reason, the
surface temperature is determined by the product temperature and, in versions with heating
jackets, by the heating medium temperature as well.
A TX identifier on the nameplate refers to this in accordance with EN 13463-1:2009, section 9.3.2
f. The maximum permitted ambient and product temperature can be found in the standard
operating instructions.
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2 SAFETY INSTRUCTIONS
2.5 Static electricity
2.5.1 Process dependent charging
In variable area flowmeters, it is possible under field conditions for charge separation to occur in
the measuring tube due to the transport of non-conductive fluids and/or when the flow comes
into contact with non-conductive built-ins (e.g. liners, floats).
For all metal devices, the measuring tube and the welded on process connections form a shield
(Faraday cage) from which the electrical field cannot escape.
In glass devices, it is basically possible for the electrostatic field generated inside the measuring
tube to "punch through" to the outside of the device. For that reason, variable area flowmeters
need to be permanently grounded by the operator by way of the process connections in order to
allow discharge of electrostatic charges.
The operator is also responsible for extending the ground continuity of the process pipeline. If
grounding cannot be made via the process connections (plastic process connections or
undefined connections), the measuring device should be connected to the described ground
potential via the connection to ground. This connection merely ensures electrostatic grounding
of the device and does not meet the requirements for equipotential bonding.
VA FLOWMETERS
CAUTION!
Use of the equipment is not permitted in areas where the following occur: processes that
generate strong charges, machine grinding and separation processes, electron spraying (e.g.
near electrostatic painting systems) or pneumatically conveyed dust.
2.5.2 Charging non-conductive external parts by cleaning
Area limits are taken into consideration with respect to the chargeability of non-conductive
external parts under atmospheric conditions. Devices for which it can be expected that
combustible electrostatic charging will occur due to cleaning are to be identified with an
adhesive sign:
CAUTION!
Achtung! Gefahr elektrostatischer Aufladung! Nicht reiben!
Caution! Risk of electrostatic charge! Do not rub!
A cloth moistened with water should be use to clean surfaces that could be loaded with a charge.
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