LAC Lift L232

Description
Lift pump error or pump contactor(K2) error (if present)

Bit 0: Measured voltage over lift pump motor(*) is higher than setpoint voltage to lift pump motor. (*) If a pump contactor(K2) is present (on OPX/N20C-range): Voltage means voltage over lift pump AND pump contactor. All error description applies not only to the lift pump but equal righted to the pump contactor too !

Bit 1: Setpoint voltage to lift pump motor is higher than measured voltage over lift pump motor.

Concerning bits 0 and 1:

1) "Setpoint voltage" = (voltage at "+"-pin of powerpart) * (PWM setpoint for lift pump motor)

2) "Measured voltage" = (voltage at "+"-pin of powerpart) - (voltage at "Li"-pin of powerpart)

3) Variable time condition:

100msec: if pump NOT commanded

1000msec: if pump commanded with PWM

Conditions of occurrence
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Result
Immediate deactivation of all functions (brake, traction, lift pump, valves, main contactor, safety relay, castor wheels, FAN)

Possible causes
Bit 0: Reasons may be: Powerpart damaged, coil of lift pump motor damaged, wires to lift pump motor cut or shortcut to GND, AIR in hydraulic circuit, brushes worn. Or secondary (contacts) side of pump contactor not closed or according fuse is blown (compare T349). ("Measured voltage" > "setpoint voltage" + 3V)

Bit 1: Reasons may be: Powerpart damaged, wires to lift pump motor shortcut to +24V ("setpoint voltage" > "measured voltage" + 3V)

Steps to eliminate the fault
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