Wired lighting bar - no power to sockets

[Ricky]

Hi there,

 

I have been trying to work this out for a few hours now, basically I have a 12 socket internally wired lighting bar terminated at 2 socaplex sockets. The problem is 1/2 the bar has stopped working. I have checked all the obvious stuff to make sure its nothing to do with dimmers and plugs and they are all fine, next plan is to look at the termination box on the bar itself. How are these boxes wired? are all the neutrals joined together or or is it 6 separate circuits. looking at the the soca sockets they all go to the bar as 2 lots of 6 separate circuits via 2 cables but access is limited wanted to do some research 1st.

 

Sorry for rambling on, hope this all makes sense to someone.

[LXbydesign]

Sounds like its either a dead soca cable your using or yes, its gonna be a wiring issue in the junction box.

 

Should be an easy wiring fix.

[Shez]

For a Socapex to six sockets, there shouldn't be any commoning going on. First google result which looks right to me is this which gives you the pinout. Armed with a continuity meter, you should easily be able to see whether it's wired up correctly.

[Brian]

You've swapped the two socas where they go into the bar and eliminated everything upstream of there?

[Ricky]

Thanks for the fast reply s, I have swapped the soca cable for a known working cable and that made no difference, the problem is that it is hard-wired from the lighting bar to backstage were it terminates at a soca socket box for all the bars. But it looks like I will have to get some access to the lighting bar and check the termination box.

[sleah]

You've swapped the two socas where they go into the bar and eliminated everything upstream of there?

 

 

Thanks for the fast reply s, I have swapped the soca cable for a known working cable and that made no difference, the problem is that it is hard-wired from the lighting bar to backstage were it terminates at a soca socket box for all the bars. But it looks like I will have to get some access to the lighting bar and check the termination box.

 

Brian meant did you swap the two over? i.e. a to b, 1 to 2, left to right or however they are labeled. And if you swap, does the fault stay in the same outlets or does it move to the other 6?

[Hilary Watts]

When you say one half of the bar has 'stopped working' do you know that it worked previously? It seems highly unlikely that a fault on the cable has caused all 6 circuits to stop working simultaneously without obvious external damage to the cable. Is it possible that the 12 sockets are wired as 6 pairs, all connected to the working cable, or alternatively that an intermediate socapex plug has been disconnected somewhere between the bar and the sockets near the dimmers?

 

Come to think of it, you say that the bar terminated at 2 socapex sockets - surely this should be at 2 socapex plugs since the sockets should be connected to the dimmers, possibly via a patch panel?

[gareth]

Very unusual for all six ways on a Soca to go faulty at once, unless you've perhaps got contractors in doing some work on the venue and they've gone through a cable, for example.

 

Let's just clarify what we're talking about here .... you have a 12-outlet IWB hanging in the roof, which is hardwired back to two panel-mounted Socapex male connectors by the dimmers - is that right? And of the twelve circuits on the bar, six of them (all fed via the same Soca connector) have now stopped working?

 

First step, as others have said, is to swap over the two Soca connectors that are going into the wall panel feeding this bar - does the fault move to the other six circuits on the bar, or stay where it is? Answer that one, and we can take it from there.

[bigclive]

Without knowing the history you can't even assume that the soca's are wired "normally". If non theatre workforce were involved in the installation you just don't know how they are wired. Keep that and the fact that if they are fed from a patch panel then there could be random feeds from several sources. If they're properly wired independent cables then swapping them would narrow down a source issue.

 

If you find that a whole soca appears to be down then I'd initially check it's actually mated properly at both ends. So many average crew don't realise that you have to mate them firmly, wiggle them, twist the lock ring a bit and do that a few times to make sure it's fully mated.

 

Next possibility. Someone snagged the cable and exposed it to unreasonable force or even chopped it completely and then hid their folly.

 

The lives and neutrals should be paired as groups of six per soca, but as I say you never know how things have been wired until you test them carefully. Backfeed through fixtures on open neutrals at patch panels are a serious shock risk.

 

And finally.... Do you definitely know that the six fixtures plugged into the seemingly dead sockets are actually working?