Faulty switch?

[winston1]

Theres more than one type of dimmer, yet externally they look alike, the transformer instructions usuallly state the type needed as the dimmer and transformers need to be compatible.

He has not got transformers which is just as well as you can't use a dimmer on a transformer for the reason I already stated.

He has got SMPS.

 

[PrenticeBoyofDerry]

I think a transformer is also faulty because one lamp was out, I replaced the lamp but it still didn't work.

I think you are very likely correct in diagnosis of this fault, even though there is some dispute over the terminology.

What should I do to get it all working?

*I would firstly. for the moment replace the dimmer with a standard rocker switch, then retry the circuit, if the circuit then trips again with can investigate further and conclude the dimmer switch has been affected and damaged by the trip.
*If the circuit does not trip, but the lamp that the switch was operating is out, then it would be wise to look at a the box that has transformer printed on it as faulty, you could test by use of a voltage indicator (two pole) to see if voltage is getting to the unit by testing at the primary supply side for 230V.
If voltage at this level (possible nearer 240V) is getting to the "transformer" then I would conclude that the transformer is faulty and the cause of the trip and requires replacing.
*If the circuit did continue to trip when replacing dimmer for rocker switch, I would prove the circuit is dead at the suspected transformer where lamp is not working and disconnect it from the circuit, re-energise and see if the fault has then cleared. If it does then we can conclude the "transformer" is faulty and causing the trip, so would require replacing with one suitable to deal with load and dimming.
The above applies to any lamp that is not working.
*If neither of the above resolve the issue then further investigation would be required to the hardwiring of the circuit or the lampholders at the fittings.

 

[Jameswren]

Thanks for the replies.

I'll buy a rocker switch, fit it then see what happens.

Is this all correct;

1 if all four lamps work then the original dimmer was faulty and the one fitted yesterday was also faulty/incompatible.
2 if the three lamps that we're working are fine, and the one that wasn't working is still out, then it's probably something to do with that white box
3 should I then disconnect that white box and replace with something of a matching spec? If that lamp then starts to work the white box was faulty and everything should be fine
4 replace the rocker with either dimmer and they should both work or they were damaged by the dodgy white box
5 if neither dimmer works I need a new dimmer to test everything


I'll be guessing at how to do anything with the white boxes so might be re-posting later.

Should I just remove the wires and leave them hanging temporarily to test the rest of the circuit?

 

[JohnW2]

For a start you cannot run a dimmer into a transformer. The chopped waveform will cause all sorts of nasty large back emf problems.

As I've said several times before, whilst I have no problem with your explaining issues of terminology to those who write about 'transformers', to post (as you often do) cryptic/sarcastic comments like the above is almost always going to totally confuse (and 'be lost on') those to whom the comments are directed. I presume it must do your ego some good to post 'clever' comments like those, but if they confuse and fail to get cross the point your're trying to make, then I think you are doing forum members (and probably also yourself) a disservice.

Kind Regards, John

 

[PrenticeBoyofDerry]

Is this all correct;
1 if all four lamps work then the original dimmer was faulty and the one fitted yesterday was also faulty/incompatible.

That would sound a logical conclusion.

2 if the three lamps that we're working are fine, and the one that wasn't working is still out, then it's probably something to do with that white box

Could also be loose connection, broken/damaged conductors of faulty lampholder

3 should I then disconnect that white box and replace with something of a matching spec? If that lamp then starts to work the white box was faulty and everything should be fine

If it starts to work yes but, I would be testing for voltage at the supply/primary side of the transformer before removing them, if you have no power to them, it is highly likely the fault lives elsewhere.

4 replace the rocker with either dimmer and they should both work or they were damaged by the dodgy white box

possibly but do not rule out a short in the circuit.

5 if neither dimmer works I need a new dimmer to test everything

A functional test will be carried out using the rocker, if the dimmer then does not work it is possible that it was supplied faulty or that damage was caused when previously energising the circuit

I'll be guessing at how to do anything with the white boxes so might be re-posting later.

Should I just remove the wires and leave them hanging temporarily to test the rest of the circuit?

Just wire as per instruction from manufacturer and don't leave dangling, at least leave conductor ends in terminal connectors.

 

[Jameswren]

So, just replaced the dimmer for a rocker and it's 3 lamps are on and the previously troublesome one is still not working.

I'll leave it a while to see if something happens as it did temporarily work yesterday with the new dimmer....

 

[PrenticeBoyofDerry]

I would assume that the transformer has become faulty, first tripping the circuit, possibly damaging the dimmer on that gang. But now the trip fault has cleared even though transformer is knackered.
But that is only an assumption, as recommended previously, you need to know if a 230/240V is present supply side of the transformer, if not it could be something upstream, if there is voltage, then a transformer or lampholder issue.

 

[DaftPunk]

I've been dimming transformers for years and years with no problems at all.

 

[JohnW2]

... as recommended previously, you need to know if a 230/240V is present load side of the transformer, ....

I presume you didn't mean to type that. If there were 230/240V on the load side of the 'white box' (whatever one chooses to call it!), there would definitely be a problem!

Kind Regards, John

 

[PrenticeBoyofDerry]

... as recommended previously, you need to know if a 230/240V is present supply side of the transformer, ....

I presume you didn't mean to type that. If there were 230/240V on the load side of the 'white box' (whatever one chooses to call it!), there would definitely be a problem!
Kind Regards, John

edited accordingly

 

[JohnW2]

He has not got transformers which is just as well as you can't use a dimmer on a transformer for the reason I already stated.

Any comments about this (and hundreds more like it)?

Kind Regards, John

 

[333rocky333]

It has been established that the SMPTs are dimmable.

Yes the white box clearly marked TRANSFORMER is DIMMABLE and has been dimmed for 5 years.

So why confuse the op further and even if it was what YOU call a transformer they can still be dimmed.

Anyway who said his dimmer chops the waveform anyway

 

[securespark]

Like I said, utter poppycock!

 

[JohnW2]

Yes the white box clearly marked TRANSFORMER is DIMMABLE and has been dimmed for 5 years. ... So why confuse the op further ...

Quite so - as I recently wrote:

As I've said several times before, whilst I have no problem with your explaining issues of terminology to those who write about 'transformers', to post (as you often do) cryptic/sarcastic comments like the above is almost always going to totally confuse (and 'be lost on') those to whom the comments are directed. I presume it must do your ego some good to post 'clever' comments like those, but if they confuse and fail to get cross the point your're trying to make, then I think you are doing forum members (and probably also yourself) a disservice.

...and even if it was what YOU call a transformer they can still be dimmed.

... and that, as well!

Kind Regards, John

 

[333rocky333]

Any comments about this (and hundreds more like it)?

Thats another story, i was taught to use special dimmers for those (known to the lighting trade as Inductive load dimmers) however our buddy BAS shot me down once with a picture of a massive dimmer.
So yet another example of confusing terminoligy

I don't know what the manufacturer means by a "resistive or passive dimmer", but either I'm wrong in what I think that type of dimmer is (and I'm going by what the words mean in an electronics context), or they are wrong to say that, as nobody makes that sort of dimmer. If they really have made a product that can only be dimmed by a rheostat then they need a good kicking.

Rheostat dimmer: