Emergency lighting circuits!

[hoppy]

Hi,

I am trying to teach myself how to wire and connect emergency light circuits. The guy I work with is not really interested in explaining things properly, so I am asking the forum for some knowledge (as I am a trainee still).

I know some of the basics, but just wondered how you guys wire your emergency light circuits from the board to a key switch and then to the lights.

I was told that you take a feed from the DB to the key switch common, then from the key switch common loop out to the lights (in our case we use a lot of klick boxes). The perm feed to the emergency light battery comes from L1 on the key switch.

I was told this was because the testing of an emergency light should not actually turn the light off so it is in emergency mode, but the light should remain fully on.

Is this correct and are there any other methods of wiring?

Also how do you guys wire lighting circuits containg key switches in say various rooms next to the light switch?

Hope this is clear.

I apologise if this is a basic question, but i would really like to get to grips with this.

Thanks

Craig

 

[Lurch]

I wouldn't wire it from the DB on a separate circuit as the emergency circuit could stay energised while the local lights are dead. Always feed emergency lights from the local circuit.

As for wiring them though keyswitches on a grid switch in each room, depends on the wiring methods used, but basically all you're doing is looping a live feed through the keyswitch to the emergency as you would a normal 1 way light switch and fitting.

 

[ProDave]

I did a PIR at our village hall recently and this is how it was wired:

There were about 8 seperate lighting circuits covering the whole building. Each lighting circuit had at least one emergency light wired to it, usually at least 2 on each lighting circuit.

In the DB (3 phase) the output from each lighting circuit MCB' is fed through a contactor, so two 4 pole contactors in the DB.

The EM lighting test point was wired to de energise both contactors, so it turned off all the lights in the whole building. You then go around and check all the emergency lights have come on.

Each emergency light is configured in "non maintained" mode, so normally they are off.

 

[Lurch]

I'd mark that as a failure then as the test switch shouldn't de-energise the entire lighting circuit, never mind all the lights in the entire building.

 

[Andy™]

I'd mark that as a failure then as the test switch shouldn't de-energise the entire lighting circuit, never mind all the lights in the entire building.

not always a failure, an MCB can be used as the test switch, this would obviously disconnect the entire circuit

 

[Lurch]

[quote name='Andy

 

[batty]

Non maintained lights ie ones that only light up under power failure need only l-n and cpc should be wired from local circuit so if lighting fails they come on. Maintained fittings that stay on all the time or are switched on need l-n-cpc and switched lived they also should be fed from local circuit so if circuit fails emergency light part will come on a keyswitch should be local to that light.

Batty

 

[ProDave]

Aren't test switches meant to be tamper proof though?

The test switch is a key switch.

If I marked the EM lighting as a fail, I know they wouldn't do anything about it. I had enough bother persuading the hall committee to allow me to fix a simple non compliance. It would take months of committee meetings to agree to a major alteration to the present lighting circuits.

 

[Lurch]

The test switch is a key switch.

Yeah, I was just veering off your example there.