20Ap2:3 Cooling Water Monitoring - ESAB Aristo Mig 3001i Service Manual

20AP2:3 Cooling water monitoring
The ELP switch in the water lock connector closes when a cooling water hose
is connected to the blue water connector on the cooling unit. The pump stops if
the switch opens. (ELP stands for ESAB Logic Pump.)
The contact in the flow guard closes when the water flow rate exceeds 0.7
l/minute. The flow guard is an accessory: if no flow guard is fitted, its
connections in the cooling unit are linked.
The following description refers to cooling units with a flow guard: units without
flow guard behave as if cooling water is always flowing.
Starting the welding equipment
1. The welding data unit senses whether the ELP switch is closed.
2. If the ELP switch is closed, the welding data unit generates a command
to start the pump. If water flow is not detected within 15 seconds, the
pump is stopped.
3. If welding does not start within 6.5 minutes, the pump is stopped.
If the water flow stops when the pump is started, the display shows
fault code 29.
The pump is stopped if the ELP switch opens.
Welding start
1. The welder presses the trigger switch on the welding torch.
2. The water pump starts if the ELP switch is closed.
3. If water flow is achieved within three seconds, welding starts.
If water flow is not detected within three seconds, the pump is stopped.
If the water flow stops during welding, welding will be interrupted and the
display shows fault code 29.
Welding stop
1. The welder releases the welding torch trigger switch.
2. Welding stops.
3. The water pump continues to run for a further 6.5 minutes.
If welding is restarted while the pump is still running, the pump will continue to
run as required, i.e. the 6.5 minute shutdown countdown is interrupted.
ca41_20_2
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S0740 800 196/E101019/P76