Washing machine blowing trip switch

The breaker that is off is an mcb, so it seems like you have a dead short between live & neutral or live & earth for it to be tripping instantly. Disconnecting one item at a time may lead you to a faulty component, ie. disconnect motor & switch on, reconnect then disconnect heater, then pump etc etc. Apparently newer machines that use a 3-phase induction motors have a converter built in to enable them to run off a single phase supply & achieve better speed control & direction of rotation, so I have learnt something as well.
 
jj4091 said:
The breaker that is off is an mcb, so it seems like you have a dead short between live & neutral or live & earth for it to be tripping instantly. Disconnecting one item at a time may lead you to a faulty component, ie. disconnect motor & switch on, reconnect then disconnect heater, then pump etc etc. Apparently newer machines that use a 3-phase induction motors have a converter built in to enable them to run off a single phase supply & achieve better speed control & direction of rotation, so I have learnt something as well.
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UPADTE - son texted this morning and said it doesn't trip when turned on without the motor in. Not sure why I didn't think to try this yesterday , except I was in a massive hurry to get the motor back home and look for non-existent brushes haha.
So, there we have it I think, the motor is responsible. Not sure how to bench test a 3 phase motor , but that's what YouTube was invented for.
 
Although you seem to have narrowed it down to the motor assy. there is usually a sensor attached to monitor the speed & direction of rotation, before you order an expensive new assy try disconnecting the sensor itself, it's a long shot but would give you a much cheaper repair if that is the problem.
 
Fab5Freddy said:
UPADTE - son texted this morning and said it doesn't trip when turned on without the motor in. Not sure why I didn't think to try this yesterday , except I was in a massive hurry to get the motor back home and look for non-existent brushes haha.
So, there we have it I think, the motor is responsible. Not sure how to bench test a 3 phase motor , but that's what YouTube was invented for.
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If the 'motor assembly' includes the inverter - it could be the inverter or motor.
 
Thanks both.
I will have chance to go down there at lunch today. If I can figure out where the sensor and/or inverter are, I will investigate. They certainly are not on the motor body itself , but will be able to track them back.
 
I suspect the 2 red wires go to the sensor, try disconnect the plug at the motor.
 
When w
jj4091 said:
I suspect the 2 red wires go to the sensor, try disconnect the plug at the motor.
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The 2 red on the motor? The clip itself on the end is moulded and not detachable.
Just googled it and it seems that is the tacho coil on the end with the 2 red wires going to it. I will take that off
IMG_9802.JPG
 
this part is speed sensor I believe - will give machine a go later with this disconnected. (although a faulty one of these wouldn't make me think it would short circuit, it would just not change drum speeds? But having said that, my knowledge is very very limited)
IMG_9803.JPG
 
I suspect you are probably correct, it probably just generates pulses that can be measured by the pcb. so unlikely to be supplied with mains voltage. You asked if you could test the coils with a multi meter & a resistance test on each of the other 3 wires to the motor body will rule out a short to earth. You should get a reading between pairs of the other 3 wires across the coils though again not sure what sort of reading you should get, not a short circuit though. Perhaps as you say one of the many vids on youtube will provide those sort of answers.
 
jj4091 said:
I suspect you are probably correct, it probably just generates pulses that can be measured by the pcb. so unlikely to be supplied with mains voltage. You asked if you could test the coils with a multi meter & a resistance test on each of the other 3 wires to the motor body will rule out a short to earth. You should get a reading between pairs of the other 3 wires across the coils though again not sure what sort of reading you should get, not a short circuit though. Perhaps as you say one of the many vids on youtube will provide those sort of answers.
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The motor gives good readings, as does the tacho/speed sensor, no shorts.
So, guessing pcb , which almost certainly rules out a fix from me, and in terms of costs it doesn't make it an attractive option.
Thanks for all your help jj4091 and others, really appreciate having people bounce ideas off and your knowledge of the problems
 
jj4091 said:
Oh well worth a try. (y)
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Yes, it was and in so doing I've learned a few things.
I don't like the 'throw away and buy new one' culture, but sometimes you got to accept it's not viable.
I see they are changing various laws in UK to force manufacturers of many devices/appliances to make them more diy friendly (called the 'right to repair law' or something.)
It would be great to see fixing things, maintaining things, soldering and wiring, on the school curriculum for all kids too.
 
One final thought. If the washer has been used or stored in a garage or similar it is not unheard of for slugs to crawl across boards & short components. If you can get access to the board it might be worth a look front & back.
 
jj4091 said:
One final thought. If the washer has been used or stored in a garage or similar it is not unheard of for slugs to crawl across boards & short components. If you can get access to the board it might be worth a look front & back.
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It hasn't, but it's not impossible that that has happened - their kitchen is a touch on the damp side behind the cupboards and appliances.
I never would have thought of that - thank you very much for all your input on this. Cheers!
 
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