Ex p control unit
Motor purge controller
Commissioning
Rev. 0
01-37A2-7D0003_Operating instructions_MPC_20210923_0_en.docx
Page 73 of 96
Operating phase
The operating phase begins with the closing of the purge gas valve.
The operating pressure must be maintained during the entire operation of the pressurised
enclosure in order to prevent the ingress of flammable substances. The electrical
installations in the pressurised enclosure are switched on via a relay integrated in the control
electronics.
If the enclosure pressure falls below the set minimum values during the operating phase, all
electrical installations in the pressurised enclosure which are not explosion-proof
themselves are switched off and a new pre-purge is initiated.
Procedure of the operating phase:
The purging valve closes and the leakage losses are compensated.
LED “p1” lights up
LED “Operate” lights up
LED “Status” lights up
Relay K1 switches on the mains voltage.
Relay K2, K3 and K4 switch depending on the configuration.
