Has anyone seen 3 phase lighting

Adp · Mar 22, 2019

It’s not me that’s wiring this someone is wanting to wire like this. 3 phase breaker 1 neutral and have the different phases to switch 3 sections of lights. That’s what they want to do, doesn’t sound ok to me

Deleted member 26818 · Mar 23, 2019

Adp said:
It’s not me that’s wiring this someone is wanting to wire like this. 3 phase breaker 1 neutral and have the different phases to switch 3 sections of lights. That’s what they want to do, doesn’t sound ok to me

What you describe there is fine.
Just to be clear though, it has to be 3 different phases.

DefyG · Mar 23, 2019

3 Phase lights - Yes
and Lighting over 3 phases - Yes

Deleted member 26818 · Mar 23, 2019

DefyG said:
3 Phase lights - Yes
and Lighting over 3 phases - Yes

As far as I am aware, there are no 3 phase light fittings.
3 phase lighting is either wired as 3 separate single phase circuits with a line and neutral conductor for each phase, or as as 3 phase circuit with the phases supplying alternate fittings and a single neutral conductor supplying all the fittings.
With the second option the neutral conductor is usually the same size as the phase conductors.
Some situations (such as street lighting) use a 5 core cable which is daisy chained to each fitting.
Other situations use a track system with clip on fittings, each fitting designed to only connect between a single phase and the neutral.

davesparks · Mar 23, 2019

Adp said:
See for the lights to work with a 3 phase breaker and one neutral could you have 3 switches or just one switch to a contactor ? My thinking 3 separate switches potentially the neutral carrying a return voltage if you work on other lights

If the lighting is fed from a three phase mcb then a switch and contactor to control the lights would be the better option in my opinion. If you want each phase on a separate switch then three seperate circuits would be the way to go in my opinion.

ElectroChem · Mar 24, 2019

spinlondon said:
As far as I am aware, there are no 3 phase light fittings.

I've seen them, but not at commercial ratings. This fitting was a multi-kW incandescent lamp for stage lighting, 3x60A filaments in a quartz bulb a foot long.

DefyG · Mar 24, 2019

spinlondon said:
As far as I am aware, there are no 3 phase light fittings.

I disagree, a while back we were researching flood lights for a particular job and a colleague discovered some 3 phase flood lights.
Not those particular ones but I found this online this morning (Spec'n below).

[ElectriciansForums.net] Has anyone seen 3 phase lighting

DefyG · Mar 24, 2019

spinlondon said:
As far as I am aware, there are no 3 phase light fittings.

I disagree, a while back we were researching flood lights for a particular job and a colleague discovered some 3 phase flood lights.
Not those particular ones but I found this online this morning (Spec'n below).

View attachment 48499

ipf · Mar 24, 2019

Adp said:
See for the lights to work with a 3 phase breaker and one neutral could you have 3 switches or just one switch to a contactor ? My thinking 3 separate switches potentially the neutral carrying a return voltage if you work on other lights

So, use 3 SP breakers from 3 Phases instead of a TP.
3 DP switches with individual outgoing neutrals to 3 light circuits.