50 hz timer motor

Well, as it turned out, the machine runs a lot faster. The timing knob finished a 120-min cycle in something like 6 minutes. The wash, drain, rinse and spin all were cut short within each function. To this day, I am still puzzled and not able to solve the problem. If anyone could shed any light on this subject, I would greatly appreciate it.

The only other possible cause would be a defective timer which could have been assembled with fewer gear sets than ought to be. But without knowing for sure the root of the problem, it doesn't make sense for me to invest another $100 to buy a timer from oversea with no English service manual available.

I may be wrong, but I can't believe the difference in frequency could make that much difference in time.

That's bizarre, does the timer use a normal syncronous motor? Either way that part draws so little current that you could very easily make a little frequency converter, all you need is an oscillator that runs at

60Hz, a couple of mosfets and some glue components.

A possibility is that the timer has developed a fault in that the gear set in the timer is somehow sticking. Most washing machine timers have a sytem where the main cam increments one notch for every so many revolutions of the timer motor. You might notice two 'barrels' inside, the rear one turning continously and the other clicking round once every revolution of the rear barrel. The rear barrel controls the main motor, and the front barrel the fill valves, drain pump and heater. Some machines have a solenoid which kicks the front barrel out of gear for certain parts of the wash - heat pause etc. This solenoid is controlled by a triac on the control module, maybe that`s where the problem lies. A continuously buzzing solenoid usually means a faulty module.

I,ve seen timers that clicked through in minutes because the little planet gears were gummed up with deteriorating grease.

Hth

Ron(UK)

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I have been in email contact. My guess is either that the motor is indeed defective (unlikely) or that the machine is supposed to move from one state to the next quickly, but should then hold in each state awaiting a completion signal and for some reason, that part of the circuit doesn't like 60 Hz. Unfortunately, the schematic is in French:

From what I can decipher, the timer uses a normal synchronous motor.

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OK, we now have a schematic in English if anyone is still awake on this issue:

It lookse like there is a signal to start the timer (page 4) and my guess is that due to either something being broken or the 60/50 Hz issue, the timer is overshooting where it should stop and so isn't waiting for the Start signal. Of course, all the magic happens in the "Module". :( :)

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There appears to be no solenoid connections on the timer, which would indicate that it`s an 'italian type' which is at odds with the machine seeming to be a variable temperature machine - on a variable temp machine, during the heat pause, the timer main cam is knocked out of gear by a solenoid operated by the module, so that the sub cam which controls the main motor direction still turns. the solenoid drops out when the wash water reaches a certain temp, then the rest of the heating cycle is governed by the time it takes the main cam to move on to it`s next position

I suspect it`s a mechanical timer and there is a problem with the pawls between the two cam barrels ( my terminology may differ from yours) If the timer has a thin card or plastic cover on top, it can usually be easily levered off to reveal the cams. If both cams revolve together all the time, the pawl mechanism which causes the intermittent drive of the front cam is jammed. Some use a maltese cross or 'Geneva Drive' for this action.

Ron

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I just verified that the inner cam and the outer cam do not revovle together all the time. It takes a number of revolutions of the inner cam to move the outer cam a knob forward.

Separately, if the machine is designed to take in cold water and heat it up internally and the timer motor is expecting feed back signal from it, would it have caused the problem if the water hose inlet was taking in hot water directly since we generally have separate hot and cold water inlets in the US? But there should be a sensor inside the machine to detect water temperature anyway...

Esther

Hi...

I wonder if it's not as simple as asking too much of that poor little hy-sync motor?

We know that they'll sync perfectly to 49 or 51 cycles, but is it possible that showing it 60 cycles it ends up "syncing" at some multiple?

If it's of sufficient interest, I have a small car inverter that changes frequency considerably with changes in engine speed... and also have a just removed (sticky, but still runs fine) that I could do some experiments with. Let me know.

And, from the purchase of the replacement defrost timer, I know that all kinds of replacement motors are available. Wonder if it wouldn't be possible to replace just the motor? We have a great old-style appliance parts store here in Winnipeg, and I'd be happy to check with them if you like.

Take care.

Ken

I think the poster said that someone had applied 50 Hz to the motor and it behaved as expected compared to 60 Hz - 5/6ths the speed.

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"Ken Weitzel" bravely wrote to "All" (05 Nov 05 03:08:49) --- on the heady topic of "Re: 50 hz timer motor"

KW> From: Ken Weitzel KW> Xref: core-easynews sci.electr > I just verified that the inner cam and the outer cam do not revovle > together all the time. It takes a number of revolutions of the inner > cam to move the outer cam a knob forward. >

KW> Hi...

KW> I wonder if it's not as simple as asking too much of that poor little KW> hy-sync motor?

KW> We know that they'll sync perfectly to 49 or 51 cycles, but is it KW> possible that showing it 60 cycles it ends up "syncing" at some KW> multiple? [,,,]

Ken,

You may be onto something here. The problem might be that the motor is

*not* syncing at all but instead is behaving as a simple ac motor. Perhaps this is due to the number of pole pieces which can't match up at 60 Hertz with the design rpm. Basically the rotor simply slips through its normal virtual electronic cage and spins really fast. It doesn't spin 1.4 times faster but instead maybe 14 times faster.

A*s*i*m*o*v

... The first rule of intelligent tinkering is to save all the parts.

That`s a posibility, but if the rear cam barrel in the timer were turning too fast, the drum wouldn`t do the correct number of turns per direction in tumble before changing direction.

Ron

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Approximately how many minutes per rev is the rear cam turning?

Ron

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My previous description maybe incomplete. Here are some hard numbers: The inner cam which is turned by the timer motor through several sets of reduction gears is turning at 1 revolution per minute. The outer cam which turns with the timer knob via an anxle has 60 notches and every 15 seconds, a notch is moved forward, so it works out to be 15 minuters for a revolution for the outer cam. This is recorded when feeding the timer motor with a black box simulating 230v and 50 hz.

Esther

That doesn`t sound correct to me, the rear cam (motor control) should as you say turn about 1 rev a minute, but the front cam which controls the fill, heat, drain and spin should I think only move on one click for each rev of the rear cam. Can you see any coil or solenoid on or inside the timer?

Ron

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Now, when running on 60 Hz, is everything just 6/5ths as fast?

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yes.

As far as I could tell, there is no coil or solenoid inside. However, the tiny motor has a metal cap on one end and I'm not sure what, if anything, might be inside. The motor is Crouzet TMX 88900048 A 32591. I tried to research the motor specification with Crouzet but had hit a dead end previously.

Esther

R> That doesn`t sound correct to me, the rear cam (motor control) should

No, I don't see any coil or solenoid as far as I could tell. The tiny motor has a metal cap on one end integrated so I don't know what's inside. It's a Crouzet motor TMX 88900048 A 32591. I already tried to research the specifications of the motor but hit a dead end before.