another Ikea transformer question

[misnomer]

Hi
found all kinds of helpful info here over the years, finally registered to ask something...

I need to replace a non functioning 12v transformer that used to feed an Ikea work lamp - single G4 halogen bulb, max specified 20W
the spec on the transformer says input 240V 50Hz, Output AC12V 1.66A

so AC output
- the old one was an all-in-one unit that plugged into a socket, connecting to the lamp flex via a DIN socket, though wiring a normal plug to a standalone unit is fine by me.
But what specs do I need to match in finding a replacement? In particular Amps
can I for example use one like this
http://www.tlc-direct.co.uk/Products/LTYT50.html
that outputs a max 11.5V, 4.3A or do I need to match the 1.66A exactly
(no intention to put a higher than 20W bulb in there)

 

[Taylortwocities]

For a single 20watt lamp @ 12volts the transformer need to be able to deliver at least 1.66amps.

It can deliver more, but not less. So that transformer will be fine, but its quite expensive once you add VAT and the £4.50 that TLC will add for an order less than £150.

Screwfix, or any of the DIY supermarkets, will be a lot less.

 

[misnomer]

thanks for the reply

good to know I can use one that delivers more than 1.66A


screwfix - mixed experiences with that place TBH...

this one http://www.screwfix.com/p/halolite-20-60va-low-voltage-electronic-transformer-240v/48058 for example seems to not deliver enough amps and has a minimum load of 35W

plus Halolite I read bad things about elsewhere. Others seem to be similar prices or higher
Also find it unclear the way many models are listed, if they deliver DC or AC

As to TLC, I've other stuff to order so delivery cost gets spread

 

[winston1]

What you linked to as a replacement is not a transformer but a switch mode power supply, though it should work.

True transformers don't usually fail. Check all the connections carefully.

How much was the Ikea lamp? Those sort of lamps are often £4.99 all in so I would not have thought replacing parts was viable.

 

[EFLImpudence]

this one ... for example seems to not deliver enough amps and has a minimum load of 35W

0.26A is on the primary - 240V.

It says 5A on the secondary.

 

[misnomer]

checked everything I can think of, through the lamp to bulb all seems fine

transformer seems to have to continuity from plug to windings on brown, not on blue
so possibly a fuse within or just a break where one lead meets the windings, under the wrapping
more under the hood than I want to go...

the lamp itself was more like about £30, so yes, close to writing it off. They don't do them anymore though and it's kind of built in to a breakfast bar, so would like to salvage it if I can


if that's a switch mode power supply (not sure of the difference) any transformers proper you would suggest?

 

[misnomer]

0.26A is on the primary - 240V.

It says 5A on the secondary.

good then, but where are you seeing that 5A?

Specifications:
12-240V. Min. dimmable load: 35W. 200mm cable. 48058: AC 0.26A current. 39220: AC 0.43A current.

 

[EFLImpudence]

What you linked to as a replacement is not a transformer but a switch mode power supply,

Whilst you may be traditionally correct, if the manufacturers call SMPSs transformers because they contain transformers and transform the voltage then they are transformers.

After all they could call them anything they wanted - Halolite Bricks, for example - and that would be what they are.


What is more worrying, dangerous and not up to the manufacturer is the incorrect use of the term 'low voltage'.

 

[EFLImpudence]

good then, but where are you seeing that 5A?

Printed on the item.

 

[misnomer]

Printed on the item.

ah... screwfix site doesn't play nice with my browser won't zoom images

thanks

still read bad things about the longevity of Halolites though

 

[misnomer]

these seem viable too and cheaper
http://www.downlightsdirect.co.uk/a...sformers/pro60-transformer-230v-12v-60va.html
though I can't see whether AC output is specified
or
http://www.downlightsdirect.co.uk/a...rs/low-voltage-transformer-60va-230v-12v.html

 

[333rocky333]

You need to look at units that have 20va or 20w minimum load or you will have problems,

 

[Taylortwocities]

these seem viable too and cheaper
http://www.downlightsdirect.co.uk/a...sformers/pro60-transformer-230v-12v-60va.html
though I can't see whether AC output is specified
or
http://www.downlightsdirect.co.uk/a...rs/low-voltage-transformer-60va-230v-12v.html

They are both 60VA and plenty for your purposes. FFS its a measly £5 transformer/switched mode power supply/whhatever.
You arent replacing a part on a Rolls Royce jet engine. Just go and buy one, it'll be fine.

Re your statement

still read bad things about the longevity of Halolites though

where did you read that. I've never had problems with Halolite transformers.
I'd say they were much more reliable than Ikea ones, apparently

 

[winston1]

What you linked to as a replacement is not a transformer but a switch mode power supply,

Whilst you may be traditionally correct, if the manufacturers call SMPSs transformers because they contain transformers and transform the voltage then they are transformers.

After all they could call them anything they wanted - Halolite Bricks, for example - and that would be what they are.


What is more worrying, dangerous and not up to the manufacturer is the incorrect use of the term 'low voltage'.

Sadly the manufacturers are wrong. A transformer has 2 (or more) windings on a laminated iron core. A SMPS is completely different though it may contain a high frequency transformer. Just because a manufacturer mis names something does not that that is what they are.

 

[EFLImpudence]

.
But it does -

Switched Mode Power Supply?