Electrical "load" advice...

I think the eyebrows were because you said 'in series' when you actually mean 'in parallel'.

Nothing particularly wrong with it AFAICS...

As others have pointed out, they'll actually be in parallel - with the cable taking progressively less of the load the further along it you go.

Series wiring is like fairy lights - ie volts have to pass through one lamp before the next. So if you wired up 12 identical mains halogens like this, they'd be running on 20 volts or so and be rather dim. There's also the problem that if one or more blows, you'd not know which it was, as they'd all go out.

All equipment designed to run off 230 volts is parallel wired.

In article , TonyK writes

I hope you mean in parallel, otherwise you won't have much light. :)

My problem with this is the number of joints you will be making; twelve for the lights plus one for the existing connection. Can you run the cable up and down to each light to minimise joints - this would be considered good practice.

To reduce voltage drop, which may cause the light at the furthest end of the chain to be slightly dimmer, I'd suggest using 1.5mm2 cable.

"Mike Tomlinson" wrote | >However I think a few | >eyebrows were raised at the thought of wiring 12 x 50w mains halogens in | >series. | I hope you mean in parallel, otherwise you won't have much light. :) | 12 x 50w = 600W, a fairish load. What else is on the circuit? Fused? | MCB?

However IEE regs require each lighting point to be assessed at 100W minimum, or actual load if greater. So the 12 points would represent a pretty much fully loaded 6A lighting circuit. And I don't know if the dinky mains halogens are permitted under the regs (or allowed in the manufacturer's instructions) to be fused at >6A - SES and SBC aren't.

Owain

The only thing that occurs to me is that switching on 12 x 50W mains halogens from cold is going to have quite a switch on surge. May well be big enough to trip an ordinary 6A MCB...

It's probably not much different from switching the 500W rectangular spotlights with the PIR that people fit for 'security', or to light the garden.

Thanks all

I didn't think it would be a problem with my unique style of "series wiring". And if you think thats bad wait till you see my parallel plumbing!

Tony

Paralell plumbing, that's quite normal!

Series pluming would be very bad though..

As you can see, THAT would be BAD!

Sparks...

Sh*t!

Knew I'd gone wrong on those showers!

Oh well....

....Saves on the water bill (If metered) though!

Sparks...

It can be done actually, tho not in that order!

Regards, NT

No s*it! (ho ho ho!)

I was under the impression that the 100W allowance is for ES and BC fittings. If the fitting takes a specific size bulb (such as a fluorescent tube or halogen bulb) then you could substitute the maximum wattage that the fitting is capable of.

Christian.

"Christian McArdle" wrote | > However IEE regs require each lighting point to be assessed at | > 100W minimum, or actual load if greater. | I was under the impression that the 100W allowance is for ES and BC | fittings. If the fitting takes a specific size bulb (such as a | fluorescent tube or halogen bulb) then you could substitute the | maximum wattage that the fitting is capable of.

I would always work on the 100W per point minimum on the basis that a fitting might be substituted at a later date with one having an incandescent.

However IIRC the OP is talking about a commercial installation where the Electricity at Work Regs will apply, so a 16A lighting circuit will be possible if the individual fittings allow use on a 16A cct and the terminals are adequately sized. The requirement that any alterations to the installation will be carried out by a 'competent' person should mean that SBC/SES luminaires aren't substituted contrary to Regs. I don't like 16A lighting in domestics because of the liklihood that SBS/SES luminaires will be used.

Owain

My NIC inspector used 60W each for the downlighters in a newbuild as the transformers were 60VA.

-- Adam

adamwadsworth@(REMOVETHIS)blueyonder.co.uk