Emergency Lighting issue - Inexperience warning

Talk Electrician Forum

Help Support Talk Electrician Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.

thumbprints

New member
Joined
Jan 5, 2017
Messages
4
Reaction score
0
Location
Nottingham
Hello,

I was running an emergency lighting test at the building I work in. One of the lights I tested came on when I ran the test, and then gradually sputtered out.

I noticed the fluorescent bulb was a bit dark so I changed it, but the light won't come on again, even at the main switch, where there are 2 other lights working fine.

The battery charging LED is still lit green. Will replacing the battery solve the issue? I would have thought it would still come on at the mains even if the battery wasn't charged.

The starter motor is not on view on the lighting & I am uncertain where to locate that ATM but thought it might be either that or the ballast, but don't want to get into that as I've not dealt with it before.

Photo of the light fitting is here.

I know this is probably a very simple thing to fix. Obviously I'm very new to this and am essentially learning on the job, but my boss is away for a while and I wanted to crack this before he is back so I was hoping I might find a solution here. Please go easy on me I'm a novice with this.

Thanks in advance,  Jez

 
Check the date on the batteries , I think they have a 5 year life although many last longer .  After a few minutes recharging the tube will at least light up for a few seconds.    Its likely to be instant start emergency ballast , so no starter switch .

Most of us , I think , go trial & error with these , so if batts mave passed useful life change them ,  if it still doesn't work then the emergency ballast has packed up .

Did you check your new tube in a working fitting ... a box of new tubes can often have one dud tube.

 
I'm slightly unclear here. Do you mean its a maintained fitting, ie one which is normally powered direct from the mains but reverts to battery if the mains fails?

Further do you mean that it now won't even come on with mains power on?  

If so, forget the batteries until you solve this.

Assuming it worked before test ensure your new tube is serviceable and that the end pins are seated properly in the holders.  

If its not so simple you are probably best leaving it until someone more experienced can help. 

If you do decide to investigate further remember there is power to the fitting even with the wall switch off, so take care.

 
Often there is one 'box' in these fittings that does mains and mains fail running. In me experience it is quite common for fitting to work in one mode and not the other, particularly after a mains fail

a block,of flats near me has had a third party do the M3 testing ( total wazzocks, did not even switch mains board back on on one floor! Don't know why it was  off as there is a switch that says 'emergency lighting test'.....W⚓️S )

anyway, their testing has toasted 30 of the fittings....some on mains some on fail....so I have got the job of swapping the lot whilst they have been potted 😃😃😃😃

 
I'm slightly unclear here. Do you mean its a maintained fitting, ie one which is normally powered direct from the mains but reverts to battery if the mains fails?

Further do you mean that it now won't even come on with mains power on?  
Hi Geoff,

Yes, that is exactly what I mean on both counts.

I returned to the bulb, checked it was in properly and retested the main switch again.

When the lights come on now, this bulb gives a quick double-flash of light just after the other lights come on, and then dies away instantly again. It also makes a bit of a noise when it flashes.

I guess if there is no quick solution, I will have to wait until my boss returns, and we talk of getting in an electrician.

I'm just concerned in terms of H&S and not having a working EL.

 
Last edited by a moderator:
I would be fairly confident in saying that this is an electronic ballast so no starter (not a starter motor, it isn't an engine) and it is this that has failed. You might find the old tube still works, but either way I would probably just change the entire fitting if it wasn't the tube, it wouldn't be worth faffing around with replacement parts.

 
Yep it's a 100 watt tube for a T8 lamp on a 8 foot fitting


Are you sure? Can't say as I have ever seen a T8 tube in an 8' fitting, not have I ever seen or heard of a 100W 8' T8 tube. Google doesn't seem to have heard of them either.

 
Are you sure? Can't say as I have ever seen a T8 tube in an 8' fitting, not have I ever seen or heard of a 100W 8' T8 tube. Google doesn't seem to have heard of them either.
Me neither....but I have been proved to know very little with being so new to,the Trade

there are probably not many people who know why they are called T5/8/12 tubes and even less that care

all the ill informed are now probably googling it and making out they knew all along

 
I used to know what the numbers meant, but my brain auto deleted it as it needed to store more stuff, I can have a guess but I will have to go onto Google to confirm. Back in a mo.

 
Back again, remembered it had something to do with the diameter but I had forgot the multiplier factor.

Time to book into the memory clinic.

 
I had never thought about it until now, but that would have been my guess as a T8 is about an inch and a T12 is about 1.25".

 
I think I may have deleted that particular gem as my brain is now full .   I just knew them as thin 'uns and fat 'uns .  I have much stuff stored in an addtional memory facility ... called  Kerch   :innocent :Salute  

 
Thanks for the responses. I will be looking to resolve this with a new fitting should the ballast replacement not work,

Jez

The tube is a T5 BTW :)

 

Latest posts

Top