Heinrichs KDSE, Руководство по эксплуатации

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Heinrichs Messtechnik GmbH
Page 10 of 14 Ex-Supplement operating manual KDSE
7. Special conditions for safe use
7.1 Environmental influences on the electronics
Environmental influences on the built-in transmitter type KDSE how the process temperature must be taken
into account. See Chapter 14 of the general operating instructions for the meter type or KDS BGK.
7.2 Atmospheric conditions
In accordance with EN 1127, a “potentially explosive atmosphere“ is defined as a mixture of air and combustible
gases, vapour, mist or dust under atmospheric conditions. Such conditions are defined in EN 13463-1, para. 1,
with values Tatm = -20 °C to +60 °C and Patm = 0.8 to 1.1 bar. Outside this range, safety parameters for most
ignition sources are not available.
Usually, variable-area flow meters operate under operating conditions outside the atmospheric conditions of
0.8 to 1.1 bar. Irrespective of the zone classification –safety parameters of explosion protection – are basically
not applicable to the inside of the measuring tube.
Therefore operation with combustible products is only allowed if a potentially explosive air mixture is not
formed inside the flow meter. Where this condition is not met, the operator will need to assess the ignition haz-
ard in each individual case and give due consideration to existing parameters (e.g. pressure, temperature, pro-
cess product, materials of construction for the measuring tube).
7.3 Ground connection
In variable-area flow meters, it is possible under operating 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 internals (e.g. liners, floats). For this reason, variable-area flow meters must be permanently
grounded by the operator by way of the process connections (flanges) in order to discharge electrostatic build-
up. 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 connec-
tions), the flow meter must be connected to the local ground potential via the flanges. This connection only
ensures electrostatic grounding of the device and does not meet the requirements for equipotential bonding.
7.4 Electrostatic charge of non-conductive parts
In hazardous areas of protection class IIC pay attention to the risk of the electrostatic charge in a danger threat-
ening amount during cleaning work on the synthetic material housing and plastics. For cleaning purposes, use
only a damp cloth.
Devices where explosive electrostatic charges can be expected are marked with an adhesive label:
WARNUNG- / WARNING-
Gefahr elektrostatischer
Aufladung! Nicht reiben!
Danger of electrostatic charge!
Do not rub!
7.5 Mechanical strength
The flow meters have undergone an impact test to DNI EN ISO 80079-36 for a low level of mechanical hazard.
Additional protective measures are required if higher mechanical hazard levels are expected.