Page 24
7) VFIELD NOT OK
3
This test is made in standby with the Main Contactor open. In this condition the
voltage on both the connections of field must be around ½ VBatt. This alarm is
generated if the field voltage is different from this value. Possible causes:
a) Frame fault on the motor to chassis.
b) Incorrect connection of the field winding to the chopper.
c) Failure of the chopper in the section relative to the field.
8) PUMP VACC NOT OK
4
This alarm is generated if the lifting potentiometer output voltage from the serial
tiller is higher than 1V. Possible causes to be checked on the serial tiller:
a) the track of the potentiometer has become open.
b) the potentiometer is not wired correctly.
c) the potentiometer itself is defective.
d) the values set during the acquisition procedure are wrong.
9) I = 0 EVER
49
This check is made while driving. If the current is not higher than a preset minimum
value, this alarm is generated and the machine disabled. Possible causes: see
"STBY I HIGH" alarm.
10) HIGH FIELD CURRENT
57
Problem detected with the field current sensor. Possible causes:
a) Failure of the field current sensor.
b) Failure of the field power unit.
11) NO FIELD CURRENT
58
Problem detected with the field winding current. Possible causes:
a) Failure of the field current sensor.
b) Field cables not connected or incorrectly connected.
c) Failure of the field power unit.
12) DRIVER SHORTED
74
The test is carried out with Main Contactor open. The logic unit verifies that the coil
of the Main Contactor is not shorted. Possible causes:
a) Driver shorted.
b) Problems in the feed back circuit of the Main Contactor coil.
c) Wiring error.
d) Fault in the protection circuit.
