Wiring up/Testing of Emergency Lighting

[DJSheridan]

Hi all,

Just wondering if anyone out there can alleviate me of a small issue.

I work in a Council owned building and the emergency lighting fitted is wired up as such that when you operate the 'fish-tail' key test switches, the power goes out to all the main lights and leaves the emergency lighting on... which I feel is the right way for it to be wired up.

Now I have to write up the Fire Risk Assessment on a new bought building (built around 2000, refurbished in 2009) but my concern is on the EL system.

It seems that the EL does not extinguish the power to the main lights when operating the test. We have even had redesign building work down to the ground floor area and the main and EL has been fitted new installation. Now when I asked why the power does not go out on the main lights when I operate the test on the EL, I've been told this is how they are wired now.

Can anyone tell me what is the correct way?

[Tom Sutton]

Check out http://www.esielectrical.co.uk/media/em_ltg_design.pdf last page and I am no expert but it appears that when you test self contained luminaries the main lighting will remain on.

[DJSheridan]

Hi Tom,

I'm afraid things still seem clear as mud.

However I'm not too sure whether they are maintained, non-maintained or self contained or if either of them are similar or not.

However in certain areas not rebuilt the EL is of the "flick test switch and the main goes out" type of set-up.

So does this mean that the whole system would need rewiring to the new 'correct' standard?

Thanks for the document you link in but it states as follows:-

"The supply to self-contained luminaires should be such as to prevent unauthorised disconnection, but should incorporate suitable means for simulating a mains failure for test purposes. The source of supply should be from the same local fuse as the normal lighting, so that in the event of a fuse failure causing the normal lighting to be extinguished, the emergency lighting is brought into operation in the same locality."

So I take it that this means the test switch facility should extinguish main lighting and only leave on the EL system.

[Safelincs]

1) if the main power fails at fuse level the emergency lights must come on

2) if the emergency lights need to be tested, only the supply to the emergency lights needs to be interrupted.

In practice you will have fish tail key switches in the power supply leading to suitable groups of emergency lights so that you don't have to switch off the power at fuse level when you want to check your emergency lighting as this would potentially cause problems with your organisation's work processes.

I guess if you have a system that can only be tested by switching the lighting power supply off altogether you would only be able to do your tests when the building is empty and if you have suitable portable light or suitable daylight in all locations you are checking. If you have dangerous processes in your company lighting might have to be on all the time, so that a central switch-off would be inappropriate.

Harry

[Tom Sutton]

The current BS 5266 Pt 1 2011 states, a test facility should simulate a main failure and not interrupt the normal lighting supply. So we have two wiring systems 1 the old and 2 the new and you have the both in one building.

Should you update the EL system then that depends on whether you can carry out the testing satisfactorily without interrupting work processes and the EL is effective, this is a decision you will need to make when you conduct your FRA.

By operating the test switch on the new wiring system you are still simulating a mains failure its just the normal lighting is not extinguishing but the emergency lights are illuminating.

Harry highlights the problems with the old wiring system.

[DJSheridan]

Hi,

Thanks for the responses.

It's swings and roundabouts in the building as some areas the key switch shuts off the power to the lights (per room, location) and illuminates the EL. The new refurbished areas the key switch does not cut power to the lights, and with some EL units being part of the main lights this poses a problem to actually see if they are working or not. Yes they have green LEDs in them but you have to look closely to see if they are actually coming on as required.

In my humble opinion the switch should be of "simulation" status IE cutting power (as it would if in a power cut, fire, etc.) and illuminating EL only.

Yes if it can cause problems in occuopied areas, but if we are to check these facilities then surely common sense would prevail and we would inform persons that we are testing the system?

In my office I am looking at a 3 tube light unit which is an EL. Now looking at the red LEd I do not know sue to looking into the light if it is illuminated or not. The only way to check is by switching the main lights off as normal and visually checking thus - or to flick the key test switch to shut off power and visually check that way.

Sometimes I wonder if progress for the better is going huge steps backwards.

Simple system would be you switch the main lights on as normal, then operate the test key switch which simulates a power cut - so you can visually see the EL works.

Yes if you are testing/servicing on the discharge test then no lights would be a problem for persons working in those areas and so this would need doing when unoccupied - so I can see the logic behind the key switches not shutting off power - but that would only be for green LEDs and not red LEDs that would be difficult to visually see - similar if 3 tube lighting is working and one of the tubes is the EL light you wouldn't know if that EL unit was working if the main lights are still being powered...

As I understand it the EL light units that (should) have LEDs on them, the LEDs are illuminated when in normal 'charging' mode but go out when in EL mode?

Again thanks anyway for your help.

[Tom Sutton]

I fully understand your frustration in my day,many moons ago, very few buildings other than entertainment and sleeping risks had EL and to test them I simple went to the switch room and threw the main switch then walked the premises. But even then there was times (hotels etc) when you could not switch the normal lighting off for safety reasons.

Now days far more complicated and EL in premises that maybe do not require it, the call progress.

[green-foam]

For what its worth I would like to point out that at least once a year the EL's should be tested (No mains) for 3 hours, so you can make sure that all the lights will last this long. You can not really expect anyone to work with just EL's on / failing.

Also just because the indication LED is lit does NOT mean the EL will work as required. All the LED indicates is that the batteries are being charged.

[DJSheridan]

Hi green,

Yes this is my point exactly. I am responsible for setting up the testing rota for the building and it is frustrating that the original system is one where you flick the test switch and all power to main lights go out and the EL is left lit - then you can discharge accordingly.

Now the refurbishment on the ground floor seems to be wired up in the 'new' way - does not extinguish power to mains.

Just to add the building is 2 story - ground floor has been refurbed and incorporates two training workshops with changing areas, reception, two classrooms, one first-aid room, cafe, kitchen, 2 main offices and 3 storage rooms, 2 sets of conveniences.

First floor has a conference room, dining area, servery and kitchen with adjourning conveniences, 11 rooms (classroom or meeting/training rooms), 5 office rooms and 3 sets of conveniences.

At the moment the only areas in use are reception and workshops/classrooms on ground floor (which are the areas refurbed).

As a further question (new-wired system), if a mains light unit houses 3 tubes, one of which is the EL tube, would flicking the test switch still discharge the batteries and finally that tube go out after 1, 2 or 3 hours depending and leave only the remaining 2 tubes illuminated as normal?

Thanks again...

[Tom Sutton]

As a further question (new-wired system), if a mains light unit houses 3 tubes, one of which is the EL tube, would flicking the test switch still discharge the batteries and finally that tube go out after 1, 2 or 3 hours depending and leave only the remaining 2 tubes illuminated as normal?

I would think so once the battery is flat, there would be no power supply to operate the EL tube but the normal tubes would still be fed from the sub lighting circuit and the emergency circuit would be isolated by the test switch.

[Guest stewiegriffin123]

For what its worth I would like to point out that at least once a year the EL's should be tested (No mains) for 3 hours, so you can make sure that all the lights will last this long. You can not really expect anyone to work with just EL's on / failing.

Also just because the indication LED is lit does NOT mean the EL will work as required. All the LED indicates is that the batteries are being charged.

@greenfoam does that fire extinguisher on your profile actually exist if so i want 1 :)

[Guest SureFire Jim]

Hi it was with interest that I read your comments, as an electrician and a fire tech all emergency lighting should be on local supply i.e. the local lighting circuit

whereas escape lighting should be on its own circuit both should have interrupt fish key for testing but no tests should be carried out by tripping the supply at source ( look at the regs, also if you replace any old E.lighting you must fit a key switch and or replace all EML's within that area bringing them all up to the proper standards.

[Tom Sutton]

Hi Jim I agree no tests should be carried out by tripping the supply at source because you would lose the normal lighting in a non-maintained system but you say" escape lighting should be on its own circuit" in a non maintained where do you get the feed from?

[AnthonyB]

Escape lighting should not be on it's own circuit unless of the maintained type or part of a central battery system as it should operate on local circuit failure.

After all escape lighting is still emergency lighting, just that provided specifically for the purposes of providing sufficient illumination of exit routes to allow safe egress.

Many older installations have to be tested by tripping the lighting circuit, obviously care needs to be taken with respect to the hazards from lack of normal lighting, but it's done up and down the country every day. Proper testing points should indeed be provided, but it's not realistic for it to happen overnight.

[Guest Repair kit]

Hi All, I've been reading through all these posts, trying to work out how Emergency Exit lights should be wired with Test switches and think I've worked it out from the varying posts here and on other forums.
The room I'm re-wiring has 3x 6ft Flourescents and (at the moment) 2x EL Exit lights. I'm going to see about adding a couple of other EL's, but for the moment I just need to connect up the existing fittings, which all seem to work.
I've done a rough diagram and was hoping someone could tell me if I've got it wrong, or if this would be correct.

 

 

Edited April 13, 2016 by Safelincs
duplication removed by editor

[Guest Repair kit]

Sorry, I know I've missed out the Neutra supply to the two EL Switches.

Edited April 13, 2016 by Safelincs
removed reference to duplication

[green-foam]

Judging by your diagram, its wired in conduit, not twin and earth. Either way, apart from the error which you state, it looks like it will work.

[Tom Sutton]

I am not a sparky so I am not sure about the technical matters but if the test switch was located closer to the junction rose, you could get one switch operating both EL's which would be easier when testing and having a test switch for every EL would mean test switches everywhere I would sooner have one test switch controlling a group of EL's.

[Guest DJ Sheridan]

Hi again... some years since I asked this question.

All is now fine as had a new contractor in to do a total rewire.

My next question (in another office) is as follows:-

Key Test Switches - 

We have keypad entry systems but a contractor has wired up the power feed to it from the Emergency lighting system - IE: when you do a key test on the EL the keypad loses power and so can't be used to gain entry into the office (this is also the case for 3 other doors into our office).
I feel this is wrong as another consumer unit (keypad) has been powered by breaking into the test circuit of the EL.

Is this right or should the keypad (regulations please if any are identified) be powered separately from the Emergency Lighting system - even though only the key-test circuit.

I feel that all emergency systems like emergency lighting should be powered separately from other units.

 

Dave

[AnthonyB]

It's all wrong. EL fittings are meant to be on the same circuits as the normal lights, otherwise they won't come on unless you get a complete power outage (local circuit failure is common).

If your contractor knew what BS5266 (the standard any professional who installs and maintains EL should have and know) said they'd have done it correctly which questions their competence

[Guest Tony E]

Just fitted Ancell/Gaurdian emergency light/does anyone know how long the light  should remain on when first fitted.

[AnthonyB]

If on battery 3 hours, if on mains then permanently if connected for 'maintained ' operation, if 'non maintained' then only on power failure.