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Discussion Starter · #1 ·
I wondered if anyone could advise please on the following:-

I am using a couple of home made 12v controllers (transistor) with an approximate currant rating of 1 amp. Solenoid type circuit breakers extracted from redundant Triang controllers are incorporated with these and work very well. I am now busy with a third controller and will need a further circuit breaker.... the construction of a scratch built item similar to the Triang wouldn't seem to be too difficult but I am interested in an alternative method and can remember reading somewhere that circuit protection can be achieved by using a standard 12v car light bulb built into the output line ; in the event of a short circuit on the track, or elsewhere , the current is directed through the bulb .....seems an excellent idea . I have tried the bulb in both series and parallel with negative results. Is there something here that I am overlooking?

Any help would be much appreciated.

Tiebar
 

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For circuit protection the bulb needs to be in series - what wattage bulb(s) are you using ?

Far better, reliable & safe circuit protection is available using self-resetting such as the Maplin AK07H rated @ 1.0A priced 99p (other ratings up to 10A available).
 

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QUOTE (Brian Considine @ 4 Aug 2008, 11:03) <{POST_SNAPBACK}>For circuit protection the bulb needs to be in series - what wattage bulb(s) are you using ?

Far better, reliable & safe circuit protection is available using self-resetting such as the Maplin AK07H rated @ 1.0A priced 99p (other ratings up to 10A available).

Hi Brian, thank you for your most useful reply.... the car bulb tried is a duel filiment ( rear / blinker) at 21 Watt and 5 watt. I will give it another go, making sure I am in series. Also taking your advice re. Maplins....never thought of trying there!

Tiebar
 
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