Another mr 16 led transformer question

[Mikefromlondon]

OP, your one looks a bit well made, and I presume it is well regulated so should run your 5watt led bulbs without any undue flicker, go for it and have a go and but remember that power supply is for a maximum load of 5 amps which means you could effectively run 10 LED bulbs in parallel with just that one electronic transformer as it is often referred to.

In either case, you have nothing to worry about, if your LEDs run flicker free, you are winner, if not then you need to worry about getting the right one for LEDs

I have wound transformer, not encapsulated which is rated at 25VA, and it weighs almost 1 kilo, so by that token a 75VA would weigh 1.5Kg

 

[ban-all-sheds]

I think I have a wire wound one so I should be ok ?

You haven't ....

Are you sure about that?

Not as sure as I was - it didn't look anywhere near large enough to be a WW, but the indications are that it is.

As the OP has more than one, there is another easy way to find out.....

 

[winston1]

That is, without doubt, a proper wire wound transformer. The switch mode power supplies have "electronic transformer" written on them even though there is no such thing. Aveatrys resistance tests prove it. The 1.5kg weight proves it.

 

[aveatry]

So its looking like the transformer is a WW one is that agreed in peoples best guesses an so good for leds which will be 5w each

If I used mr16 leds elsewhere in the house then I would just "borrow" them and see but mostly everywhere is gu10 led and cfl. And the only way to see is to buy the mr16s and try, but if it was no good then changing the transformer is a job much later in the year and I am left with the leds
In trying to find out about this transformer I have read that these old WW ones use energy themselves, and so it would probably be better to change it for a new one anyway, but like I said earlier that is not a quick job and is way down the list for me. But at least it looks like I can now pop some LEDs in and start benefiting from them straight away.

 

[JohnW2]

OP, your one looks a bit well made, and I presume it is well regulated so should run your 5watt led bulbs without any undue flicker, go for it and have a go and but remember that power supply is for a maximum load of 5 amps which means you could effectively run 10 LED bulbs in parallel with just that one electronic transformer as it is often referred to.

I think that most of us are now agreed that it is almost certainly a wire-wound transformer (and hence not 'regulated' in the electronic sense).

Kind Regards, John

 

[Gees]

As the OP has more than one, there is another easy way to find out.....

Back to back???

 

[JohnW2]

Back to back???

That's what I assumed he was thinking of - but he might have had something more destructive in mind! If, by any chance, it were not wire-wound ... I've never tried putting power into the output of an SMPSU, but I doubt it would do any harm!

Kind Regards, John

 

[Mikefromlondon]

OP, how ironic, the guy I have just been helping install his 12v 5W LED bulbs, after installing 8 in total 2 rows of 4 on 2 separate Electronic Transformers, after about 5 minutes of running they started to flicker, reason was the electronic transformer was getting warmer and so regulating down, so those electronic transformers are no good for LED lighting.

So I told my mate that he will need proper wound type transformers, and guess what he said wait he might have some and he pulled out exactly the one you have posted the picture of, it is indeed a proper transformer, and quite heavy, and is filled with resin, has two terminals on each side, so i wired those and absolutely perfect, better and very stable.

So go ahead absolutely no problems, you could wire up to 10 LED bulbs on one single transformer but if you keep 8 per transformer you will run them cool, and not to its maximum loading.

 

[Gees]

That's what I assumed he was thinking of - but he might have had something more destructive in mind! If, by any chance, it were not wire-wound ... I've never tried putting power into the output of an SMPSU, but I doubt it would do any harm!

Providing the positives are connected together ( and the negs of course) then all would be well... not the other way round though..

 

[Gees]

As the OP has more than one, there is another easy way to find out.....

Or a scope of course...

 

[JohnW2]

Or a scope of course...

Yep - or a capacitor and resistor of appropriate values and a multimeter.

Kind Regards, John

 

[JohnW2]

Providing the positives are connected together ( and the negs of course) then all would be well... not the other way round though..

I'm not sure which you would call positive and which you would call negative with AC

With an AC-AC SMPSU. I doubt it would make any difference which way round one connected it (the output is probably connected to little, if anything, other than the secondary of the HF transformer) - the real question is what might happen when the stepped-up AC voltage on other side of the tranny impacted on the circuitry there (which is used to quasi-DC).

Kind Regards, John

 

[aveatry]

OP, how ironic, the guy I have just been helping install his 12v 5W LED bulbs, after installing 8 in total 2 rows of 4 on 2 separate Electronic Transformers, after about 5 minutes of running they started to flicker, reason was the electronic transformer was getting warmer and so regulating down, so those electronic transformers are no good for LED lighting.

So I told my mate that he will need proper wound type transformers, and guess what he said wait he might have some and he pulled out exactly the one you have posted the picture of, it is indeed a proper transformer, and quite heavy, and is filled with resin, has two terminals on each side, so i wired those and absolutely perfect, better and very stable.

So go ahead absolutely no problems, you could wire up to 10 LED bulbs on one single transformer but if you keep 8 per transformer you will run them cool, and not to its maximum loading.

HEY ! well fancy that, I actually have two sets up there that at the moment running 3x 20w each, so I could at some time in the future remove one and run all 6x5w led all off one transformer.
I have just got back from screwfix with the bulbs and will be popping them in soon, I feel like I need to invite one of you lot to do the grand switch on
I will report back later with some before and after pictures

 

[Mikefromlondon]

I have just got back from screwfix with the bulbs and will be popping them in soon, I feel like I need to invite one of you lot to do the grand switch on
I will report back later with some before and after pictures

I don't know if you saw my other post at 4.17 or at No 23, where I just happen to wire two identical transformers exactly like yours, and each running 4 x 5watt LED bulbs with absolutely no problems. So Good luck. Yours is a proper wire wound transformer, and not an electronic transformer.

 

[aveatry]

I have just got back from screwfix with the bulbs and will be popping them in soon, I feel like I need to invite one of you lot to do the grand switch on
I will report back later with some before and after pictures

I don't know if you saw my other post at 4.17 or at No 23, where I just happen to wire two identical transformers exactly like yours, and each running 4 x 5watt LED bulbs with absolutely no problems. So Good luck. Yours is a proper wire wound transformer, and not an electronic transformer.

Yes I saw that- I don't know how you are viewing the posts but my quote about the switch-on is in the same post that I acknowledged your job you did for your mate.


WAIT STOP - forget that, its my fault as I quoted your post but the wrong one
I have now gone back to my post and put in your post that I meant to post, it should all make sense now-- sorry