Atlas Copco ZR-55, Instruction Book

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Description
Two condensate traps are installed: one downstream of the intercooler (MTi) to prevent condensate from
entering compressor element (Eh) and one downstream of the aftercooler (MTa) to prevent condensate from
entering the air outlet pipe. The condensate traps are connected to Electronic Water Drains (EWDi and EWDa
respectively).
The condensate enters the electronic water drain via inlet (1) and accumulates in collector (2). A capacitive
sensor (3) continuously measures the liquid level. As soon as the collector is filled up to a certain level, pilot
valve (4) is activated and diaphragm (5) opens outlet (6), discharging the condensate. When the collector has
been emptied, the outlet closes quickly without wasting compressed air.
When the controller registers a malfunction, the red alarm LED starts flashing and the electronic drain valve
will automatically change to the alarm mode, opening and closing the valve according to a sequence as shown
below.
This condition continues until the fault is remedied. If the fault is not remedied automatically, maintenance
is required.
Testing the Electronic water drain
Functional test
Instruction book
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