2
DEVICE DESCRIPTION
16
VA FLOWMETERS
www.krohne.com
09/2022 - 4000419908 - AD VA Mech Ex Gb-Db R08 en
2.9 Ignition hazard assessment / protective measures
Non-electrical variable area flowmeters were subject to an ignition hazard assessment in
accordance with ISO 80079-36. The following table lists the ignition hazards considered and the
protective measures carried out or to be carried out by the operator.
Device type
Ignition hazard Constructive protective
measures
Construction site protective measures
(note special conditions!)
All versions
Electrostatics
Electrostatic connection
between conductive
components, ground
connection device
Include device in the equipotential bonding of
the hazardous area.
For installations in hazardous areas of
group IIC, observe the notes for the
elimination of electrostatic charge.
Impact of
sparking in
measuring units
Float stop in measuring unit
Eliminate pressure surges in pipelines.
Impact of
sparking on
surfaces
Materials (without titanium)
None
Shock
resistance
Glass cones
Tests with low energy
If the degree of mechanical risk is higher,
protective measures on-site must be taken.
Shock
resistance
Metal cones
Tests with high energy
None
Surface
temperatures
None, as no self-warming
occurs
Note max. permissible product and ambient
temperatures.
Oxygen in
conjunction with
titanium
measuring units
None
Products with an oxygen content higher than
21% V/V are not permitted.
H250 M40 / H250
M8MG
Impact of
sparking on
titanium
surfaces
Marking in the type marking
(Ti)
Equipment with titanium surfaces may only
be used in shock-resistant areas.
DK32 / DK34 /
DK37
Marking with material code
(e. g. 3.7025, 3.7035 or 3.7055)
on the measuring unit
H250/C...
Electrostatics
Minimum conductivity of the
medium
≥
10
-8
S/m
Note the minimum conductivity of the
medium.
VA40
Min. conductivity for liquids
≥
10
-9
S/m
Flow rate
≤
5 * V
max
with dust-
free gases and liquids
Note the minimum conductivity of the
medium.
Note the maximum flow rate.
GA24
Flow rate
≤
10 * V
max
with
dust-free gases and liquids
Note the maximum flow rate.
DK46 / DK47
DK48 / DK800
Flow rate
≤
20 * V
max
with
dust-free gases and liquids
DK46PV / DK47PV
DK48PV / DK800PV
Min. conductivity for liquids
≥
10
-9
S/m
Flow rate
≤
20 * V
max
with
dust-free gases and liquids
Note the minimum conductivity of the
medium.
Note the maximum flow rate.
DK3x HT..
Corrosion
None
Exclude corrosive environmental conditions.
Table 2-6: Ignition hazard assessment / protective measures
Summary of Contents for DK 46
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