Tripping after 30 mins will be caused by a breakdown in insulation in the motors windings and for that serial number you would need motor part number(###) ###-####br />
If you take out the plug from the side of the motor and power up the appliance again, does this still happen?
Let me know how you get on.
It is possible, however, there are possibilities of other causes too... the transformer for instance...
Can you read a wiring diagram so that you can test for the source of the fault once it has happened?
The wiring diagram for this model is attached.. you should be able to use it to trace power loss following your trip.
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