Washing machine motor tripping RCD?

[T i m]

Hi All,

The washing machine (AEG Lavamat 6100 Digitronic), seeing the recent attention the tumble dryer has had (when I replaced it's bearings) has decided it want's some TLC and started tripping the RCD, again. ;-(

It did it a while good ago when a good blow through with the air line and a new pair of brushes had it running ok (I changed the bearings and seal a few years before that).

So, with the motor earth isolated from 'earth' all runs ok, earth the motor and the RCD trips. With the motor running I generally see ~30VAC between the motor chassis and ground.

The fault seems to between the field coils (stator?) and earth, measuring around 18k ohms on my DMM, even after another good blow through with an air line.

I am wondering if some carbon has got down to where the external wiring joins the stator windings and is conducting to the motor frame?

The next step may be to try and strip the motor further and see if I can get the stator coil out and see if I can see / measure anything?

Any other thoughts / ideas please?

All the best ..

T i m

p.s. I guess if it was on the non RCD side of my CU I wouldn't even know there was a problem (well, till it caught fire or whatever)?

[Graham.]

IINAE, but if I was I reckon the inventor of the RCD will gave contributed

significantly to my annual income :-)

When I had the same problem it was carbon deposits on the plastic brush-carriers. With the action you have outlined you will find the cause easily.

[The Natural Philosopher]

Don't waste your time. I did all that, and nothing was apparent. Put in a new motor, and hey presto, megohms or better.

IIRC it was ALSO about 18k..odd asint it.

Of a crap hoover machine..

I know what you mean. It happened suddenly and irrevocably on ours.My guess was insulation had broken down under some kind of vibration.

XCHG price on a new was about 50 notes. Less hassle than spending hours..

[The Natural Philosopher]

In my case it wasn't. I had a meter across just the coils and frame. 18k.

So don't expect too much.

[T i m]

Hmm, well I think they were new when I did similar last and certainly they are much much younger than when it happened the first time from new. Today I gave them a good wipe over and like I said, there seems to be no measurable resistance between the brushes / rotor and the motor ground (in contrast to the stator and ground). :-(

Well I think I have found the general area but not the cause per-se.

FWIW I would like to carefully take the motor further apart and just see if I can see where 18K could exist.

All the best ..

T i m

[T i m]

Hmm, well I was working on the thought that a new motor would be 'expensive' and potentially the time to retire the machine.

It is isn't it.

Well the motor on this one actually says AEG .... I was sort of expecting it to say Zanussi ..

The actual windings are very low ohms of course (7 or so) so this 18k obviously isn't a winding directly shorting on the frame so insulation breakdown seems likely, however, I'm still hoping that there is some carbon brush build up actually between where the flex joins the winding and that a wash off might sort it (I said hopefully ...) ;-)

Ah, if it was only that (all in) then you might be right ... and if it gives us another couple of years ...

Where did you get yours from please?

All the best ..

T i m

[Harry Bloomfield]

I too would be inclined to try giving the stator windings a wash down, you have nothing to loose. It might be as simple as the exposed bare wire at the joint - as per your own suggestion. Out of curiosity, what fluid were you thinking of using for the actual 'wash'?

[T i m]

Apart from time and I have more of that than money at the moment ;-)

Or even a loose insulating sleeve with carbon powder stuck up it and across to the motor frame. I think the stator is sitting on a plastic bobbin so in theory it shouldn't be in direct contact with the motor frame anywhere and ignoring this RCD issue seems to run ok.

Good question Harry. This morning I had intended buying some paraffin and a metal bucket (or finding a suitable metal / fuel proof container) and giving the whole motor a good dunking.

Or wondering if I could afford an ultrasonic tank big enough to hold the complete motor.

Instead I blew it through with my mates airline and washed the business end out with some brake cleaner (I think it has naphtha as one of the ingredients) and that seemed to work ok. After I had dried / blown it out I re greased the brush end bearing (spray grease in beside the bearing shield) and span it up to work the grease in and re-fitted the cleaned / blown out brush holders (and that cct measures ok).

I initially thought I needed something cheap / safe enough to be able to submerge the entire motor that would neither affect the insulation nor plastic bits but be 'solventy' enough to shift the carbon (hence the paraffin)?

What would you suggest?

All the best ..

T i m

p.s. I think I've found a couple of site selling new motors and they are around 220 quid! I wonder if a local motor 're-winder' would do it cheaper?

>

[The Natural Philosopher]

A tiny man in a tiny shop off the Exning road in Newmarket, Suffolk.

The point being that if you totally destroy it in an effort to find the problem, it may not be part exchangeable.

Which reminds me. I have a radio stat thats ceased to deliver its all.

Must go and slap some DC on ot and see what gives..

[T i m]

Hmm, that's only a gallon away from Norf Lundin in the Rover. ;-)

Understood. However I am generally very careful with such things .. make suitable marks so it can all go back together etc. The bottom line is that if I *knew* there was an exchange motor out there for 50 quid I'd probably leave this one alone and go straight for it. But as I'm not that lucky the more practical solution /for me/ is to see if I can (gently) take it to bits and locate the problem. If in so doing I make the motor un-exchangeable I'm no worse off, I've still got a duff motor on what I think I've found is a 1993 washing machine so will probably have to get a new machine?

Good luck .. ;-)

All the best ..

T i m

[The Natural Philosopher]

find a place that does *exchange* motors.

[T i m]

Yes, I get it, but of the searches I've done for appliance spares on the net (all the real shops were closed yesterday evening) those that do 'exchange' units, don't show one for my model.

But I'm still looking! ;-)

Now if you happen to have some details for this "tiny man in a tiny shop off the Exning road in Newmarket" please ... ?

All the best ..

T i m

p.s. I just spoke to the spares place I got my tumble dryer parts from .. £317.99 for a new motor ...

[adder1969]

On mine, I managed to find the same motor but for a different model and had to swap over the belt pulleys. Otherwise I think mine was more like =A3120.

[tony sayer]

In article , T i m scribeth thus

Bloody extortionate!. Watts it made out of?..

[T i m]

Sfunny, I was just wandering around ebay and you can buy a new motor for other brands for about 60 quid and that got me wondering ...

Assuming most of these motors are similar (stator, brush / rotor, tacho wires) and most seem to have the poly-V belt drive spindle it's possibly just down to the mounting bracketry (nothing that couldn't be re-fabricated with a bit of ingenuity)?

What' sooo frustrating for me is this motor sits and works happily (and very quietly) on the floor ... so near yet .... :-(

I've been looking around at replacement machines and it seems, like the toaster, you have to spend a lot of money to get to the build and running quality of our existing machine. Like, something that I'd not considered was the running noise. Many reviews state that the newer (cheaper) ranges of machines can be noisier (especially with the higher spin speeds) and I can't say I've EVER walked past our AEG when it's at any part of the cycle and considered the noise levels (suggesting it's pretty quiet)?

One site suggested that to find the build quality / sound levels / expected lifetime of our existing machine we would now have to go to a Miele (top level AEG being just under a 'std' Miele?).

All the best ..

T i m

[T i m]

Indeed ...

Well, at that price I guess they are hand made on demand (I can't see anyone stocking them eh)?

All the best ..

T i m

[The Natural Philosopher]

Go to yellow pages and look under domestic appliance repairs.

Get phoning.

BTW here is a copy of a reply to an Email I sent last night. ;-)

---------------------------------------------------------------

Thank you for your enquiry to the Sunvic Technical Helpdesk. Detailed our response to your query. Hopefully this will address your issues. If you have any further queries, do not hesitate to contact us either by phone [phone] or e-mail [e-mail]

We don't want to have disgruntled customers. You should get significantly longer life from this product. If you supply me with your address I'll arrange to have a replacement sent to you free of charge.

----- Original Message ----- From: To: Sent: Tuesday, January 22, 2008 2:51 AM Subject: TLX 1206

[<me9]

I recently replaced my aging AEG with a miele. seems quite good. The denmise of the aEG was a programmer fault. Several years ago I replaced the motor with a second hand one from a local shop due to a burnt out armature. I may still have the old one. If you can post a picture somewhere I could check, and I could post on the stator if it would fit for the cost of the postage.

[T i m]

Have been ..

Have been, as yet, zilch. (Even spoke to a motor rewinder who said it would cost more than a new machine).

Result, now get a new motor for my AEG please!

All the best ..

T i m

[adder1969]

I think with mine it was something like the actual replacement model was old/obselete/expensive and the newer ones were for faster spin machines but had exactly the same frame and connections. The only difference was the pulley. I spent quite a bit of time looking on the internet for my model *and* for others to see what fits what. That meant I could search on more terms to see if there was anything out there. I think my replacement was something like 55 quid.