Problem with downlighters

[mte29]

Hi I have changed 2 transformers that feed 5 downlighters each on the same circuit.

The first 5 work fine, but the second 5 are fine when turned on but then after about 30 mins start to go dull and gently flicker. After about 5 minutes of this they go back working fine for about another 30 minutes or so.

If i disconnect the transformer and reconnect when the dull flicking is occurring the lights work fine again but then start to flicker again after a short period.

I have changed the transformer but still no luck.

Wondered if anyone knows what could be causing this problem?

 

[RF Lighting]

What is the rating of the transformer?

How many lamps are there, and what are the ratings of each lamp?

 

[mte29]

Hi,
Transformer is 60VA.
Bulbs are 20W - 12V.

The thing is both sets of lights are the same and both sets have the same transformer but it is only one set that are having the problems with.

 

[RF Lighting]

So you have 5 lamps rated at 20W each, connected to a 60VA transformer???

 

[ColJack]

not so good with the maths me thinks...

just in case you missed RF's implication..

5 x 20W = 100W
60VA = 60W

100W > 60W..

it's the thermal protection cutting in on the transformer.. to protect itself

you need at least a 100VA transformer, but a 120-150VA would be better.

 

[mte29]

Thanks guys, i was being dense and mixing W's and V's. Won't make that mistake again. (Hopefully).

Thanks