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toroidal transformer replacement

Robert C

New Member
Hello all.
Looking for an expert to advise me on replacing a failed toroidal transformer on a massage chair. The control circuit is functioning, but the actuators are not. Voltage testing indicates no output from this transformer. An ohm check of the input leads (black & white) shows as open (failed?). Doing the same check on the output leads (any combination of the blue/yellow) indicates connectivity.
20190909_134400.jpg
As near as I can figure the following is the closest to a replacement part as I can find online.
Hamond 1182P22 (https://www.newark.com/hammond/1182p22/transformer-toroid-44v-225va/dp/54X7533).

Should I buy one?
Thanks for the advise.
 

ronsimpson

Well-Known Member
Most Helpful Member
Toroidal Transformer, Power, 225 VA, 2 x 22V, 44V, 10.22 A,
Interesting what the description is when you order the transformer but the data sheet gives me the idea that it is rated at 10A at 22V (or 5A at 44v)
120438
16A
120439
 

MaxHeadRoom78

Well-Known Member
Extremely rare for a transformer of that size especially, to go open circuit, most likely a supply conductor to winding connection, unfortunately the primary is usually wound first which makes it difficult to repair, the other scenario, which is rare for a toroidal, is a thermal fuse buried in the winding, these are also very hard to uncover.
There is a outfit called AnTek that makes toroidal transformers and will still I believe, put one together as a custom build.
Max.
 

Nigel Goodwin

Super Moderator
Most Helpful Member
I thought about, maybe there is a thermal fuse in the transformer lead. Probably not.
I would imagine the most likely cause is a failed heat fuse inside the transformer - a far more likely failure than the winding itself going O/C - and despite what others have suggested, heat fuses in toroids are commonplace.

Such devices aren't replaceable, particularly in a toroidal transformer, and it's always possible that a failure elsewhere (such as a S/C rectifier?) has overloaded the transformer and blown the heat fuse.

Certainly in the past there used to be plenty of adverts for custom winding toroidal transformers, at fairly reasonable cost - I presume such services are still available?.
 

MaxHeadRoom78

Well-Known Member
My experience over many decades with Toroid's is I have yet to come across one that has a thermal fuse buried in the winding, in any case I think they are an inane idea.
To bury a couple of cent fuse inside a winding that cannot be replaced and renders the ($$) device inoperable is ridiculous.
I have only found them in small, ~ 50va, E I types.
Max.
 

Nigel Goodwin

Super Moderator
Most Helpful Member
My experience over many decades with Toroid's is I have yet to come across one that has a thermal fuse buried in the winding, in any case I think they are an inane idea.
To bury a couple of cent fuse inside a winding that cannot be replaced and renders the ($$) device inoperable is ridiculous.
I have only found them in small, ~ 50va, E I types.
Max.
I've replaced numerous ones where the heat fuses have failed, with some you can actually get to them and bypass them - and I've done that a couple of times and kept the old transformers for my personal use - obviously you can't do that for a customers repair job.

While I agree it's REALLY annoying, the fact remains it's an important safety device - and has become so over the last few decades.
 

MaxHeadRoom78

Well-Known Member
I beg to differ that is a required safety device where it is used, an overloaded or shorted turn transformer will draw excessive current and can be easily detected by the right external fusing.
Fitting a buried/non-replacable item rendering the component useless, infers that the OEM/end-user is not capable of making the right engineering choices.
It is Very rarely, if ever, seen on Industrial transformers from 3ph and 1ph in control circuitry/enclosures.
Always external fusing/breakers are used
Max.
 

tvtech

Well-Known Member
Most Helpful Member
MaxHeadRoom78

You have no idea what happens in the "real world". People replace fuses with wire. Things than burn down. That's why those safety measures are put in place by toroidal manufacturers for example.

We all know the theory here. No need to teach us.

Go real world issues and you will understand.

tv
 

MaxHeadRoom78

Well-Known Member
MaxHeadRoom78

go real world issues and you will understand.
tv
That is strange, I have been involved with industrial Electrical and electronic control for 70yrs, also Radio and TV service.
And have qualifications in all.
so I believe I am qualified to have an opinion on the subject.
My posts were not directed as any kind of put down, but expressing my opinion, for which I believe I am qualified to have!:rolleyes:.
 

tvtech

Well-Known Member
Most Helpful Member
No sweat. It's just that I've seen some crazy stuff happen here in Africa. It's a manufacturers nightmare lol to stop stupids and their ways of abusing stuff.
 

Nigel Goodwin

Super Moderator
Most Helpful Member
That is strange, I have been involved with industrial Electrical and electronic control for 70yrs, also Radio and TV service.
I've hi-lighted the key word, I presumed tvtech was referring to that when he said 'real world'? - if you're used to an industrial environment the 'real world' outside, that people live in, is entirely different. It's a bit like the different world at Universities, which bares no resemblance to the real world outside.

I remember having a long discussion years ago with a guy, about the PCB's used in Pace Digital Satellite receivers, he was complaining about the poor quality of the boards (which were 4 layer) - in my professional opinion the boards were the highest quality of any in the domestic market.

Eventally, it turned out that he was in the industrial market, and paid MORE for the bare PCB than the entire satellite receiver retailed for :D
 

tvtech

Well-Known Member
Most Helpful Member
I've seen clothes pegs used as insulators keeping live mains wires apart. Paper used like insulation tape on mains. Copper wire fuses that end up destroying copper tracks and everything else in the way.

It's a miracle that so few house fires are heard of here.
 

MaxHeadRoom78

Well-Known Member
I was also a service manager for 8 yrs for a large TV Radio department, so have actually met the 'public'!! :rolleyes:
Believe me, ANY area that uses any kind of electrical or mechanical equipment can be, and often is, prone to gross miss-usage.
But, There are very few areas where the safety objectives for a piece of equipment renders the (high priced) object unusable for future use, upon activation..
And in my opinion, should Never occur.
That is my whole point.
Max.
 
Last edited:

MaxHeadRoom78

Well-Known Member
The thread seems to have got lost somewhere, I was referring to the object stated in the OP.
If the general opinion of those here is that the fitting of a non-replaceable fuse in a high priced item is OK.
My point is that Transformers are one of the most widely used component in the electrical world.
And fortunately having installed many hundreds of all different stripes, the only one I have come across made this way is small ~50va versions, where the replacement cost is minimal.
Also fortunately my manufacturer go-to, AnTek, does not use this practice.
Also aparently it is frowned on here to have an opinion!
Max.
 

Nigel Goodwin

Super Moderator
Most Helpful Member
The thread seems to have got lost somewhere, I was referring to the object stated in the OP.
If the general opinion of those here is that the fitting of a non-replaceable fuse in a high priced item is OK.
My point is that Transformers are one of the most widely used component in the electrical world.
And fortunately having installed many hundreds of all different stripes, the only one I have come across made this way is small ~50va versions, where the replacement cost is minimal.
Also fortunately my manufacturer go-to, AnTek, does not use this practice.
Also aparently it is frowned on here to have an opinion!
Not frowned on at all - and no one has suggested that they 'like' heat fuses in transformers (as far as I know?), simply pointed out that it's a commonplace, and down to the dirt cheap prices.

I've never heard of AnTek? - but presumably they would happily provide 10,000 transformers with heat fuses in if your ordered them? (I'm presuming AnTek are a transformer manufacturer?).

I don't think I've ever seen a generic transformer with a built-in heatfuse?, but I can't say I've ever looked for one? - but major manufacturers generally don't use generic off the shelf transformers anyway.
 

tvtech

Well-Known Member
Most Helpful Member
I guess I'm really tired of fixing things for stupids. They bring really stuffed up CRTs that have stood for years. (They don't like flat screens anymore cause they too easy to steal)
Now I sit and fix. Lovingly. Customer collects and is happy.

Next morning the CRT is back. Back cover loose and.... they dropped it. Now I'm PISSED OFF.

WTF is wrong with them? Now the set has cracks that are hard to repair cause it's a old set that has old surface mount resistors under the board. Like 1999 style.
GRRR.
All I'm saying is I'm over helping stupids.

Anyone remember that Tech that I was training with all his qualifications and stuff?

Well, he's still alive. But appears to be getting stupider by the day. Keeps hitting his head when I ask him a technical question he "knows the answer for". One day he's remembering...next day he can't. It's like he and his brain are not on the same page.

And it's killing me. I can't handle much more of this.

That's all I have to say.
 

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