Overheating transformer.

[TonyV]

I am using a 50W (230V - 12V) transformer to drive a 5W halogen lamp.
It works fine but the transformer gets very hot after about 30 minutes or
so.

Can someone please explain to me why it overheats so quickly?
Should I perhaps use a lower Wattage transformer?

Thanks.
TonyV
South Africa

 

On Tue, 3 Feb 2004 00:04:11 +0200 TonyV <bigt@webmail.co.za> wrote:
| I am using a 50W (230V - 12V) transformer to drive a 5W halogen lamp.
| It works fine but the transformer gets very hot after about 30 minutes or
| so.
|
| Can someone please explain to me why it overheats so quickly?
| Should I perhaps use a lower Wattage transformer?

Does it get hot if the transformer is energized but the light is off (either
by using a switch on the 12V side, or by removing the bulb)?

A transformer will lose some power, of course. They do get hot. Maybe you
can find a way to accurately measure the temperature rise.

Transformers used for electric power distribution often have temperature
rise levels of 80C, 115C, or 150C, depending on the design class. They
are rated for maximum of 220C typically, so with 40C ambient temperature,
even the hotest ones have a 30C margin.

Small transformers tend to be less efficient, and it's not surprising that
they get hot. Just how hot is enough for that one is unknown. Is it sealed?

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[Ken Taylor]

"TonyV" <bigt@webmail.co.za> wrote in message
news:1075759493.624098@proxy.jhb.stormnet.co.za...

I am using a 50W (230V - 12V) transformer to drive a 5W halogen lamp.
It works fine but the transformer gets very hot after about 30 minutes or
so.

Can someone please explain to me why it overheats so quickly?
Should I perhaps use a lower Wattage transformer?

Thanks.
TonyV
South Africa

What is the type number of the transformer. A lower wattage unit is unlikely

to help if there is some other problem causing the heat.

Ken