KROHNE H250 M40 ATEX II2D Ex t-II2G Ex d EN - Manual (Page 17)

OPERATION
5
17
H250 M40
www.krohne.com 07/2012 - 4002069601 - MA H250/M40-Ex-II2GD-AD R01
Operation
5.1 Start up
Start-up is only permitted when the variable area flowmeter:
• is correctly installed in the system and connected.
• has been checked for the proper state with regard to its installation and connection
requirements.
• and the electronics compartment have been properly closed (pressure-resistant casing or
dustproof housing) and the applicable special lock has been fitted.
The user of the system must have it checked before start-up in compliance with the national
regulations for checks before startup.
If the device needs to be configured due to the existence of an explosive atmosphere, this can be
done using the supplied bar magnets. There is no need to open the housing as it can be done
through the glass window of the electronics compartment or digitally via the signal output
(HART
® interface)
5.2 Operation
Variable area flowmeters must be operated in such a way that they remain within the maximum
and minimum permissible temperatures and pressures and the electrical limit values.
Variable area flowmeters may only be operated if the equipment parts necessary for safety are
effective in the long run, and are not rendered inoperable during operation.
When it comes to flammable products, the measuring sections must be included in the periodic
pressure tests of the system.
Opening the housing of the electronics compartment (equipment protection by flameproof
enclosure or dustproof housing) in hazardous areas is only permitted in a de-energised state.
5.3 Electrostatic charge
In order to avoid ignition hazards due to electrostatic charge, variable area flowmeters
may not be used in areas where the following appear:
• processes that generate large charges,
• machines with friction and cutting processes,
• spraying of electrons (e.g. in the vicinity of electrostatic painting systems),
WARNING!
Ignition risks caused by pressure surges, impact or friction must particularly be avoided when
titanium measuring units are used.
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