Low voltage lighting wiring

[rbel]

Is it viable to have 2 electronic LV lighting transformers connected to the same LV light?

Eg one 250w transformer to feed 6x35w lights and one 50w transformer to feed just one of the 35w lights. A two way (relay) switch would ensure that only one transformer receives power at any one time.

The idea is to be able to use a remote control to switch all the lights or just the one and from a remote relay point of view it appears to be simpler to switch just the mains supplies to each transformer than to switch both mains and the LV supplies.

[Bill Wright]

Why not have an extra light on its own circuit?

Bill

[Dave Liquorice]

Just to clarify, there is a total of 6 lamps and you want to switch all on/off or just one of those six on/off.

I wouldn't connect the LV sides together even with proper transformers rather than electronic ones. Switching the mains is no problem, just arrange the relay switching possibly needing two relays.

o / / Live ----+---------o R1a | | | o----+----+ TFR +---- Five lamps | | | +------------+ | | | | o | | / | | / | +----o R1b | | | o----+----+ TFR +---- One lamp | | | | | | | o | | / | | / | +---------o R2a | | | o----+

R1 switches all six lamps on. R2 switches one lamp on. This might not do exactly what you want as if the lone lamp is on it won't go off with the other 5 when R1 is switched off. It might be possible to do that switching with logic on the relay control side.

If the transformers are real transformers, ie lumps of iron and coils, I'd be wary of running a 35 W lamp on a 50 W rated transformer. The voltage can rise and significantly shorten lamp life.

[rbel]

Dave, many thanks for the response and ASCII diagram.

I was thinking of using a remote relay with three positions, off, L1 or L2 as follows

L1 ----250w TFR----lamps 1 to 6 /

240v +---Relay common-Off \ L2 ----50w TFR -----lamp 6 only

This would mean that both electronic transformers would end up with LV connections to lamp 6 although clearly not live at the same time. The transformers would be from the Varilight premium range

[Andy Burns]

But how is the supply from the 50W transformer *not* going to find its way to lamps 1 to 5, if all lamps are connected to the 250W transformer?

[rbel]

A very good point! Back to the drawing board.

[meow2222]

no

Won't work.

Use one transformer, and a 240v coil relay to switch the feed to 5 of the lights on or off.

NT

[Fredxx]

Use the 250W transformer for the 5 lamps and the 50W one for the remaining lamp.

Just switch use a SPST relay for the 250W set with the single lamp permanently lit.

I am assuming there is an overriding light switch somewhere.

[rbel]

I also want to relocate the existing light switch and not wanting to chase walls and run cable from very awkward loft space I am planning on using a wireless remote wall switch which will activate the relay(s).

It looks as though I will need to use 2 relays as simple on/off switches, one for the 250w transformer and 5 lamps and one for the 50w transformer and the 6th lamp.