Ex p Control unit
APEX
py
Commissioning
Rev. 0
01-37A2-7D0006_py_Manual_Exp-Control-Unit_20210923_a_en.docx
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Setting for "Leakage air compensation" digital valves
When using digital purge gas valves, the leakage
air needle must be adjusted during initial startup
or when the leakage air quantity changes.
With proportional valves, the leakage air volume is
controlled automatically via the valve.
This must be set so that enough purge gas enters
the pressurized equipment to maintain the
required operating pressure (po).
The leakage air needles are located on each side of
the valve body on the valve.
The side that may not be accessible should be closed.
Procedure
Set the pressurized equipment in an operationally safe manner.
Measure the internal pressure via a pressure gauge or use the Ex p
control unit for pressure acquisition
Close pressurized equipment, activate purge gas supply
Read off the resulting internal pressure on the gauge
If the internal pressure is too low, increase the amount of purge
gas at the leakage air needle valve. This is done by turning
counterclockwise
If the internal pressure is too high, reduce the amount of purge gas
at the leakage air needle. This is done by turning the leakage air
needle clockwise.
Configuration for gas applications
Ensure that the electrical wiring has been connected as
described in the relevant operating instructions and that the
purge gas supply has been connected.
If the Ex p control unit is in programming mode (parameter switch
activated and password entered), the display of the pressure
values is in Pa. Settings are made in the Pa.
To carry out the configuration, log into the WEB interface at the user level.
Ex p settings – Manual purge
After the applied purge gas valve is set, the Ex p specific parameters are set
according to the following sections.
Follow the individual chapters for the correct procedure to the parameters to be
performed.
