Question for Electrical Geniuses -- Multipole Switch

[Cadence]

Any chance of removing it and burnishing the contacts?

[StoneCrab]

Originally Posted by Dsanduril

Don't think it matters, but 5-6, 12-13, 14-15, 16-17 are SPDT contacts, only one set can be active at a time (i.e. if you have 5-5a you can't have 6-6a).

At the bottom of the drawing (row E) there are a bunch of numbers, I think these are cycle position numbers.

Great analysis Dsanduril. I noticed that the row of numbers in row E has a corresponding numbered terminal vertically above the number in that row. For instance the last number "12", has wire 12 directly above it going to the switch. 4 and 8 are at the top of the diagram.

This looks like the manual for your machine: https://manuall.de/eudora-eu-456-01-...waschmaschine/

I had fun with Google Translate:
Fling
Spool Stop
Spin Without
Spin With
Double with Spool Stop
Without Spinning
Fine with Spin
Fine with Spool Stop
Fine without Spinning
Gentle Drying
Dries Normally

(it didn't help)

[StoneCrab]

I've had some luck freeing up contacts with a spray can of contact cleaner and a lot of back and forth motion.

[Dockhead]

Originally Posted by Dsanduril

The way I read it that switch controls leg 2 of the mains power. Normally neutral but according to the drawing the machine doesn't care which leg is neutral and which hot.

I suspect that switch is piggy-backed on the rotary switch. When the connection is made 1-2 the neutral is connected brown-blue and the wash functions have power. When that switch is connected 1-4 the neutral is connected brown-violet and the dry functions have power.

In dry mode 14-14a then provide neutral to the motor/drum controller. In wash mode 15-15a provide the same function.

So, in short, yes, I would say the problem could be that switch. Testing would be as simple as putting the rotary knob in dry and then jumpering brown-violet.

There could be other interlock logic that prevents the drum turning when no heat, I don't see it, but some of the other switches are a bit opaque/mysterious as to function.

One more test before opening things up, does it not work in low dry mode as well? And does the drum not spin?

I'm grateful for the thought which goes into these replies -- thanks to you and the others.


Yes --


Behavior is identical, low dry and high dry.


Usually the dry cycle will start, but then it fails. Fails like power cut to the machine. Once there was a burning smell -- I guess the switch contacts.


I have gotten almost an another year of service out of it since the problem started, by cutting power to the machine before switching the cycle, then powering up via the main panel switch rather than the machine switch. Sometimes will work for a whole cycle like this.


I'm sure it's one of the contacts which carries the main part of the power.

[Dsanduril]

Well, that 1-2/4 switch at 1/2 A/B on the drawing carries all power but uses a different set of contacts for dry vs. wash, so I would put that on my list of likely suspects.

There's also some switching going on at drawing 4B where 9-9a and then 4-4a get their hot leg, but it's a little more complicated and the image is too blurry to make out the symbol details. This device looks like it sends the hot leg down to the drum in dry mode, but also looks like it uses a different set of contacts in wash mode for the same purpose - but not sure on this one, as can't see the details.

Do you ever wash with hot water? Just curious, as this would run the water heater contacts. I've been focusing on that neutral switch, but I suppose the hot switch could have contacts that handle wash just fine (pretty low load) but not dry. This would be ruled out (at least somewhat) if you use the water heating element, an then the wash load would be relatively high as well.

[Dockhead]

Originally Posted by Cadence

Any chance of removing it and burnishing the contacts?

I did remove it, but there doesn't seem to be any non-destructive way to get at the contacts.

[Dockhead]

Originally Posted by Dsanduril

Well, that 1-2/4 switch at 1/2 A/B on the drawing carries all power but uses a different set of contacts for dry vs. wash, so I would put that on my list of likely suspects.

There's also some switching going on at drawing 4B where 9-9a and then 4-4a get their hot leg, but it's a little more complicated and the image is too blurry to make out the symbol details. This device looks like it sends the hot leg down to the drum in dry mode, but also looks like it uses a different set of contacts in wash mode for the same purpose - but not sure on this one, as can't see the details.

Do you ever wash with hot water? Just curious, as this would run the water heater contacts. I've been focusing on that neutral switch, but I suppose the hot switch could have contacts that handle wash just fine (pretty low load) but not dry. This would be ruled out (at least somewhat) if you use the water heating element, an then the wash load would be relatively high as well.

Great analysis. The CF brain trust!



YES, I always use the washer heater element, and no problems with that. Even Kochwäsche -- boiling hot. No issues.


So sounds like the 1-2/4 switch at 1/2 A/B, eh?

[StoneCrab]

Now that you have the switch out, can you see any part numbers on it?
Any manufacturer, codes of any type?

In my experience, appliance manufacturers use a short list of common components. You can find the same control boards and switches in several different brands and models.

If you get lucky, and find some numbers on it, tracking down replacement parts may be possible... if the existing one can't be revived.

Now not to ask the obvious, but did you give the manufacturer's tech support a call or email?

[Dockhead]

Originally Posted by StoneCrab

Now that you have the switch out, can you see any part numbers on it?
Any manufacturer, codes of any type?

In my experience, appliance manufacturers use a short list of common components. You can find the same control boards and switches in several different brands and models.

If you get lucky, and find some numbers on it, tracking down replacement parts may be possible... if the existing one can't be revived.

Now not to ask the obvious, but did you give the manufacturer's tech support a call or email?

I corresponded with both the appliance manufacturer and the switch manufacturer. It's dead out of production and no remaining stocks.

[Cadence]

Originally Posted by Dockhead

I corresponded with both the appliance manufacturer and the switch manufacturer. It's dead out of production and no remaining stocks.

A rotory switch seems to be a thing of the past. I'd love to find a washer that had one. Twist it to wash and that's it, stops when it is done. You might check if someone sells refurbished in your area. Buy one for the switch or see if he has canalized one for parts.
That is probably pissing up wind but worth a phone call.

[Dsanduril]

It looks like there are two places that could interrupt power to both the heater and the drum. The first is the switch in the neutral leg. The other place would be over in column 4, the hot leg looks like it goes to device 5 (thanks to SandCrab for picking up on that). From there it can go to "B" or "8" (?), that feeds 5-5a and 6-6a these are used for wash so we know that set of contacts is OK. In the other direction it looks like it should connect 5 to H (drum) and H to C (dryer heater) at the same time.

I think, but the symbol is hard to see, that device 5 is a relay/contactor, it seems to have that function, as do the other numbered devices. Which then makes me think it is at least as likely, if not more, than the neutral switch. Contactor/relay contacts are generally more susceptible than switch contacts.

That's a long way of saying that I think there are two devices that meet the criteria (heater fail, drum fail, no dry, wash still works) and either could be faulty. In all of that, I think the good news is that I would not, at this point, be as suspect of the rotary switch itself. If it is either of the other devices then a suitable replacement could probably be sourced.

[Dockhead]

Originally Posted by StoneCrab

Now that you have the switch out, can you see any part numbers on it?
Any manufacturer, codes of any type?

In my experience, appliance manufacturers use a short list of common components. You can find the same control boards and switches in several different brands and models.

If you get lucky, and find some numbers on it, tracking down replacement parts may be possible... if the existing one can't be revived.

Now not to ask the obvious, but did you give the manufacturer's tech support a call or email?

Yes, that was of course Plan "A". Last year, I called both Eudora/SOBA, who made the machine (a Eudora EU457), and Dreefs, who made the switch. The switch is a Dreefs 031154. It looks like the older and more expensive version of this -- the Dreefs 031130 -- would also work, and is probably a better/pre-value engineering version of it too.



But none of the parts are available anywhere I could find. I looked pretty hard.


So Plan "B" is to wire around the problem somehow, and you guys have really helped a lot in figuring out how to do that.

[Dockhead]

Originally Posted by Dsanduril

. . . That's a long way of saying that I think there are two devices that meet the criteria (heater fail, drum fail, no dry, wash still works) and either could be faulty. In all of that, I think the good news is that I would not, at this point, be as suspect of the rotary switch itself. If it is either of the other devices then a suitable replacement could probably be sourced.

OK, maybe, but wiggling the switch makes it come on again. Isn't that strong evidence that it's the switch?


Also, this is not the first problem I had with that switch. The main power feed contact burned out a couple of years ago. I successfully wired around that with a toggle switch.

[johnn33]

Hi
These people in England may be worth contacting
https://www.thermaco.co.uk/product/r...tton-switches/
John

[AKA-None]

Rotary switches don’t usually carry much current and a typical failure mode is loss of tension in the contact material. If the switch is in position and you tap it then does it make contact? If so then it’s the switch. I’d check for a current carrying relay. But the I can’t see great detail on my phone.