Emergency lighting help

[Jon West]

Good afternoon,

yesterday we had a power cut in our care home, 2 emergency lights did not kick in. They kick in on the key flick test which i do every month but they do not kick in when i switch off the MCB in the consumer unit. We have just had new batteries put in and they are fully charged. The green led is on when the power is on. We do have a contract for maintenance with Lowe and Oliver but as maintenance manager if i can fix it it will save the call out fee. Any ideas why they would work on a flick test but not a full power cut?

 

[westward10]

Do they sustain illumination with the test facility for a period of time say 10 minutes.

 

[Jon West]

Do they sustain illumination with the test facility for a period of time say 10 minutes.

Yes because they have just had new batteries.

 

[westward10]

I am just wondering if you are quickly flicking them on with the test facility to verify operation but when you turn off the breaker there is sufficient time getting to the fittings from the board for them to fail in other words they briefly illuminate and then fail.

 

[Octopus]

Have they ever worked properly

 

[Pete999]

try turning off the MCB again and see if the green mains LED is still on. this would indicate that they were fed from elsewhere.

What Tel said^^^^^^^^^^^^^^^^^^^^^

 

[davesparks]

The lights illuminate when the test switch is operated.
The lights do not illuminate when power to the entire installation is lost, ie. a power cut.

That is not likely to be caused by the lights being fed from a different circuit.

My guess would be that the test switch is incorrectly wired so that it is connected to the switched live terminal thus switching the light on rather than simulating a power failure.
If this is the case then it probably doesn't have an unswitched supply at all and so the battery hasn't been charged.

 

[Zdb]

the light kicks in on EL flick test, but not when the mcb is switched off.

If they're non maintained and work on the flick test then they will work in a power cut.

You must be switching the wrong MCB off.

 

[davesparks]

If they're non maintained and work on the flick test then they will work in a power cut.

You must be switching the wrong MCB off.

He has stated that they did not work in a power cut.

Don't assume that the test switch has been wired correctly,

 

[Zdb]

But he also stated that the green indicators are normally on, and switch off when in test.

 

[davesparks]

But he also stated that the green indicators are normally on, and switch off when in test.

Which could just be the lamp obscuring the LED

 

[westward10]

Depending on where the board is they may illuminate for a short period then have failed by the time he gets there. He may only be flicking the test facility quickly but need more info and he seems to have gone.

 

[davesparks]

Depending on where the board is they may illuminate for a short period then have failed by the time he gets there. He may only be flicking the test facility quickly but need more info and he seems to have gone.

It's seems unlikely if they have new batteries, but of course is not impossible.

 

[Lucien Nunes]

The OP doesn't say explicitly that the charge indicator goes off when the test switch is operated, only that it did when the supply was pulled. The only consistent explanation seems to be Davesparks'...

 

[westward10]

It's seems unlikely if they have new batteries, but of course is not impossible.

May have replaced batteries due to previous failure when in fact that wasn't the issue, like you say maybe no permanent supply or the fiitings have duff charging parts.

 

[Jon West]

Have they ever worked properly

If they're non maintained and work on the flick test then they will work in a power cut.

You must be switching the wrong MCB off.

100 percent the correct mcb as all the lights in that corridor go off when the power is cut.