Emergency Lighting Repair

[SparkyChick]

Hi all,

This is kind of prompted by the existing emergency lighting thread, but is subtly different.

I do some work for a charity in Cardiff and on my last visit I was asked to investigate the failure of a light in a toilet. Turns out, it's an emergency luminaire that uses a couple of CFL lamps and a high frequency electronic ballast/charger/inverter unit.

It simply didn't work at all under any circumstances. I investigated and I believe the problem was caused by a failed electrolytic cap on the ballast board. The batteries were also shot and didn't appear to be holding any form of charge.

Further investigation revealed another unit in a similar state.

I've purchased new ballast units designed for this purpose along with new battery packs and have rebuilt one unit and am going to do the other on-site. They are the same spec in terms of operation and run time. Aside from the obvious electrical and operational checks, as these are emergency lights do I need to do anything other than repair and replace as I'm not changing operation, run time, illumination levels or anything, I'm just bringing them back into service?

Just don't want to end up on the wrong side of the rulebook as it's a charity and effectively a public building.

Thanks

 

[Octopus]

It's probably cheaper to replace the unit........ Certainly quicker...

 

[SparkyChick]

I did try and find a replacement, but I've not had a lot to do with emergency lights and wasn't able to find a good price for a suitable unit. Fitting wise, time would be the same (the one needs rewiring as the pleb who fitted them used chocblock and tape for the enclosure when connecting it up - I've already sorted out the one mess)

The other issue I had when looking for replacements, they aren't surface mounted, they are recessed into the ceiling so replacing the entire unit would mean fixing the ceiling first (it's pretty low) which would have meant more cost and well, given it's a charity it's a bit of a balancing act... save a bit here and end up costing more there.

 

[westward10]

Replacement is the ideal situation but finding matching luminaries can be difficult. I see no problem with what you have done but I always note any works carried out on a safety system like emergency lighting in their log book, if they have one.

 

[davesparks]

You should carry out a duration test on the emergency fittings once they have had time to fully charge the batteries

 

[SparkyChick]

Replacement is the ideal situation but finding matching luminaries can be difficult. I see no problem with what you have done but I always note any works carried out on a safety system like emergency lighting in their log book, if they have one.

Thanks for that tip, didn't think about that, but yes, very good point.

You should carry out a duration test on the emergency fittings once they have had time to fully charge the batteries

Thanks for that tip too, though this is one I had already planned on. Had hoped to get them fitted today and then go back Monday and test them after they'd been on charge over the weekend.

 

[The Ghost]

are they maintained or non...? Seems unusual to be high frequency and so old sounding.

 

[westward10]

Maintained.

 

[SparkyChick]

They are maintained. I've not seen them in action because obviously neither of them were working, but as best as I can tell, when the switched live is on, both tubes are illuminated and when the power to the permanent live goes off only one of the tubes will come on.

The original ballasts were Harvard Engineering DE 226-3, driving two 26w TC-D tubes with a 3.6v three cell NiCd pack, providing a 3 hour runtime. Harvard don't make them any more so they are being replaced with Tridonic PC2x26-3 Combo units.

The fixtures themselves are like a red thermosetting plastic I believe, with lots of different screwholes in for different ballasts so these just drop right in with a tweak of mounting screws. And aside from branding and polarity, the new battery packs are identical to the ones that have failed. Just a pain in the butt to open the containers for them.

 

[SparkyChick]

And tweaking the battery connector polarity is a pain in the backside as well, kind of like Molex crimp terminals with a couple of spring clips holding the crimp in the body... pain in the butt. They did come supplied with new battery leads, but the ones on the fitting appear to be fire proof cable, so I'm reversing the polarity and using the existing connectors.

 

[westward10]

I know the packs you mean they are good replacements.

 

[Richard Burns]

As you are just doing a maintenance replacement of lights you will only need to ensure that your replacement lights are fulling the purpose the previous lights were doing, so long as the time of operation on battery and the light intensity in both emergency and non emergency situations is the same there should only be operational EM lighting checks for those fittings: do the batteries charge, do they operate once charged, do they function for the time stated (obviously doing the full discharge test at a time when the EM lighting will not be required just afterwards).
You will just do your usual electrical checks for changing a light fitting and you should note the maintenance of the fitting and the tests in their fire safety log book (if they actually have one).

 

[SparkyChick]

The thing about the light intensity is I can't verify that because I had/have no working reference, so I can only assume that it will be OK based on the fact the tubes in use are as supported by the original ballast, unless of course they have the original plan which I could compare against.

The only time I can guarantee they won't be needed is during the day. One is by the exit door and the other is in the loo. Not sure about when this particular part of the site is in use, think it could be a bit transient, being put into use when needed as it's a women's refuge.

I've already done the basic checks on the part of the circuit that supplies the one I removed as it needed replacing with a properly contained junction (was chocblock and tape) and functionally, the circuit is fine. PL is on with the MCB and off with the test switch, SL is on/off with the light switch.

 

[Richard Burns]

Because you are using the same lamps and voltages the intensity will be the same as originally specified and as this a maintenance replacement of a matching (unchanged) light source you do not need to compare to the EM lighting plan and verify the entire install, you only need to ensure that the items you fitted still work the same as the original parts. You have done the electrical checks for the electrical side of things.
As an aside if the lights are switched then they are non maintained lights as they are not on all the time. (though I may be wrong)

 

[static zap]

A local village hall had a date sheet for caretaker bod to
verify operation ( took little notice of .. )
operated for a 30% of every so often , full period anually .
Taking extra care with public places !