Home Repair Manuals Hotpoint WMA32 Dismantle & Repair
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2.8
Tacho Generator / Motor
Motor
Tacho
Attributed faults
Attributed faults
•
Noisy
* Distribute speed wrong
•
No Drum Action * Motor Spins
•
Earth Leakage (Trips fuse box)
* Erratic Spin Speed
* Bangs on Spin
About the Motor
After date code 26 a different design motor was introduced and both types of motor were
in production at the same time. The newer motor had the wiring connection block at the
front (The end the belt fits on) rather than the end where the Tacho is located. Although
both motors will fit and may seem interchangeable they are not. The wiring connections
are different on the newer motor; the wiring plug is the wrong way round, and by turning
the connector upside down to make it fit will only blow the motor circuit.
About the Tacho
The short version is the ‘Tacho Generator’ is a slightly off set magnet inside a field coil,
on the rear of the motor, which sends information to the module; this information
determines the speed of the motor, and whether or not the drum is out of balance.
If a tacho fault is encountered, such as the distribute speed being too fast, or machine
going straight into spin when switched on, the motor must be changed because there
is no adjustment on these tachos.
The motor bearings can cause almost as much noise as the drum bearings if left too
long without attention, they can be changed but normally the motor is replaced.
The brushes very rarely wear down on these motors but should be checked anyway.
Internal faults would be the windings which are fitted with a thermal overload or the
armature. Once again they can be changed but the motor is usually replaced.
Earth leakage, caused by the carbon from the brushes, can trip some milliamp fuse
boxes. This carbon sits inside the motor housing and form a bridge across from the
case to the wiring, (only a problem on some very sensitive boxes).
