Tracking lights.

[Mattrod]

Hi Sparks.
A client has two tracking low voltage light systems in his house. Both have two lamps (50w 12v) on them, fed from one of those old massive round transformers (300w). There is a intermitent fault when the lights a turned on, and the CB trips. All the cable is sound and checks.No other faults on the circuit, so I think the transformer is abit knackered.
My question is can I replace the transformer with a new one, say a Halolite 50-300w electronic one. I think it's OK, but just want to check.
Thanks

 

[davelerave]

are you sure it's not just inrush on a b type mcb

 

[telectrix]

just what i thought.

 

[ackbarthestar]

I've had the same problem. use a C or D6A . Check the cold resistance of the secondary windings and do a quick sum..

 

[davelerave]

i would stick with the C if loop impedance readings allow it

and everything checks out ok

 

[Mattrod]

Is there anyway of finding out if it is an inrush? It would make sense, I think. How do you check the cold resistance of the secondary windings? And how would this help me in my problem solving. Havn't come up against this, so would be nice to have some blanks filled in.

Thanks for the replies, by the way.

 

[Knobhead]

Quickest way is try a type C.
Or if you have a clamp meter with peak hold try that.
To be honest I don’t know if domestic meters have this feature, the ones I used at work did. It was a god send with motors.