Wiring LV ceiling downlighters Ask questions and find answers to many subjects relating to electrics and electrical work

[woody22366]

I have an existing ceiling light which I would like to replace with LV down lighters..,Can I have 2x 12v transfomers at 210w each runnning off the existing..,

[ericmark]

What are you asking? One sentence talks about low voltage the next extra low voltage? 210 watt x 2 low voltage would not on it's own cause a problem although you need to consider it as a whole not in isolation. 210 watt x 2 extra low voltage would depend on type of inverter or transformer used as the inrush could trip out a B6 MCB and you may need to use a C or D type.
Although it would be nice if one size fitted all sorry it doesn't work that way and I will guess you have not a clue what I have talked about? You really do have to give a lot more information.
Do remember to earth below 50 volts is extra low voltage and anything between 50 and 500 volt to earth is low voltage.
Also quartz halogen even with low voltage can have a problem with inrush that's the current drawn on switch on so the more switches the better.
And to help you can normally consider Watts = VA = Volts x Amps so 460 Watt = 2 amp.
Eric

[woody22366]

Thanks for that..,Basically what I was asking is can I run 2 x 210watt transformers from 1 existing 240v lightcircuit..,I need to do this to have 5 No. 50 watt and 1 No. 35 watt downlighters..,

[woody22366]

[quote="woody22366"]I have an existing ceiling light which I would like to replace with LV down lighters..,Can I have 2x 12v transfomers at 210w each runnning off the existing..,[/quote]

[ericmark]

In theory there should not be a problem but in practice in-rush can cause the MCB to trip. Not all power supplies for extra low voltage lamps will permit loads below a set limit and to replace the lights latter with lamps that fall into to 40 lum per watt may be a problem. I would plan to use LED or Cold cathode lights even if at the moment you use tungsten The new lamps are longer than old and I would say in general GU10 holders using low voltage lamps are more flexible than extra low voltage and I would only use extra low voltage where water is involved like ponds and bathrooms.
Eric