Maytag MXS20 Programming Manual page 69

DIAGNOSE FAILURE 300-301-302: OC-ERRORS (OVERCURRENT)
1. Check if there is a short circuit on the output of the
Inverter (loose motor cable wire, motor windings, screws
or other loose parts inside the motor terminal box...)
2. Disconnect the motor power supply wires from the Frequency
Inverter and try again.
DIAGNOSE FAILURE 303-304-305: OV-ERRORS (OVERVOLTAGE)
If the DC-voltage on the capacitors is too high, the Inverter will generate OV error.
1. Check if there was a severe unbalance during extraction,
which can be caused by putting only half loads in the
washer.
2. Check if the supply voltage is too high.
3. Check if the fault is persistent.
DIAGNOSE FAILURE 306: THT-ERROR (INVERTER OVERLOAD)
If the output current of the Frequency Inverter is abnormal high for some time, the Inverter will go into THT-alarm state.
1. Check if the power supply is sufficiently high enough and
stable during extraction with a load.
2. Check if the drum rotates normally by hand.
(no abnormal restriction to turning)
3. Check if the motor windings are OK.
DIAGNOSE FAILURE 307: THM-ERROR (MOTOR OVERLOAD)
If the motor current is higher than allowed for a longer-time, the Inverter will activate the electronic over-current protection to keep
the motor from overheating and the Frequency Inverter will go into THM-alarm state.
1. Check if the drum rotates normally by hand.
2. Check if the motor windings are OK.
3. Check if the fault is persistent.
DIAGNOSE FAILURE 309: OLT-ERROR (STALL PREVENTION)
The output frequency has dropped to minimum because of a current limitation.
1. Check if the power supply is sufficiently high and stable
during extraction with load.
2. Check if the drum rotates normally by hand.
(no abnormal restrictions to turning)
3. Check if the motor windings are OK.
DIAGNOSE FAILURE 313/315: OPT/PUE-ERROR (OPTION FAULT/PARAMETER UNIT LEAVE OUT)
If the Inverter does not receive requests from the wash computer (= no serial communication), after about 10–30 seconds, the Inverter
will go into OPT/PUE-alarm state.
1. At the end of the wash cycle check, if the power supply
contactor for the Frequency Inverter switch is turned off
on all phases.
The OPT/PUE-ERROR happens occasionally by a very short main power supply interruption. (Due to a power interruption, the Frequency
Inverter was not able to reset itself correctly.)
=> In such a case, the contactor should not be replaced. The Inverter should be reset with a continuous supply of power.
Repair the short circuit.
If error persists with motor power supply wires disconnected,
replace the Frequency Inverter.
Always put a full load in the washer.
If too high: reduce the supply voltage.
If the fault is persistent, contact Maytag.
Correct the power supply.
Repair/remove obstruction or clean what is necessary.
If shorted or open windings are found: replace the motor.
Repair/remove obstruction or clean what is necessary.
If shorted or open windings are found: replace the motor.
If the fault is persistent, contact Maytag.
Correct the power supply.
Repair/remove obstruction or clean what is necessary.
If shorted or open windings are found: replace the motor.
Replace the contactor if the problem is persistent.
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