What amp rated transformer to run car light via mains please

22 Mar 2010
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United Kingdom
I want to run a Rubbolite 150 (orange emergency flashy light), which is designed for installation on top of a car/van, inside my boys bedroom off mains 240v. He's obsessed with nee-nars at the moment!!

The light has a 12V 55W bulb and small motor to turn the mirror round.

Allowing a few watts for the motor (has no markings on it) I'm thinking a 12V 5A mains transformer will be ok. Something like this:

Does this sound ok?

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I would suggest the motor will be drawing more than 5w, especially on start-up. With a 55w bulb (which, if the information I have found on the net is correct. is a Xenon bulb, and thus has its own control unit) this will mean that a 12v 5A power supply will not be sufficient. Also, Xenon lamps run very hot. If it is sat on the top of a van/lorry the heat dissipates, not so in an enclosed space, so that is another consideration.
You'll probably need to add a rectifier to the circuit as the motor will no doubt be a DC one rather than AC
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Or have a search through the disco lights on Ebay, you may find a 230V version for sale, possibly in blue
Or have a search through the disco lights on Ebay, you may find a 230V version for sale, possibly in blue
Excellent idea, thanks. Already found a nice blue one from Maplin's outlet.. :D

TBH, was struggling to find a high enough rated transformer to drive the rubbolite. Looked at low voltage halogen transformers (kind used in kitchen lighting) which are readily available in ~150VA but they've an AC output, not DC.
The advice to use a lower power lamp is very sensible. Bright flashing lights in a child's bedroom can have long term adverse affects on health and sleep patterns.

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