Concerns on the EL system

[Tom Sutton]

Just wondering if anyone out there can explain to me.
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 a new building (built around 2000, refurbished in 2009) have concerns 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 refurbished the ground floor area and a new EL has been fitted.  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?

Can anybody please help.

[nearlythere]

Just wondering if anyone out there can explain to me.
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 a new building (built around 2000, refurbished in 2009) have concerns 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 refurbished the ground floor area and a new EL has been fitted.  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?

Can anybody please help.

The desired means of testing EL Tom is to operate a test switch to activate them without interrupting the general lighting. Your first arrangement is little different to isolating the general lighting circuit from the consumer unit which was the old school way.
When you consider that the annual test requires EL to operate for at least 1 hr. to knock off the general lighting say in an office or other room with little or no natural light can cause disruption during that period.
The best way is the second you describe.

Certainly for signing a system off or if I was doing a fire risk assessment I would knock off general lighting circuits momentarily to ensure the configuration is correct. All too often I find EL wired back to one or two spurs off the mains and not to the sub circuit. For an annual test you are essentially testing the performance of the unit.

[Owen66]

Perhaps the counterpoint argument is that operating the key switch with method 1 gives a positive indication that the emergency lighting does work for the monthly "flick test", and it also is immediately obvious which luminaires are the emergency ones. I've had several fire officers insist on this over the years.

For a duration test, then it could be argued that this is undertaken at times of low risk so having the main lighting off shouldn't be a problem.

If there are sufficient key test switches (rather than one or two at the DB location, then all you'll be doing is isolating lighting in the room or zone of test.

Method 2 has drawn comments in the past that it's not possible to "see" what is happening with emergency lighting as other luminaires operating at full mains are swamping the relatively low output of emergency conversions.

Ideally, the method of testing should have been considered by the designer (he has that duty under CDM) and agreed with the client and building control - either method being acceptable but with relative advantages and disadvantages in different circumstances.

You'll find all sorts of rules which have no basis in reality such as inclusion of visual indication at the test switch to indicate mains healthy or system in test depending on what day of the week it is, that key switches should have line of site to the luminaires concerned etc etc.

Personally. tend to favour method 1 but with additional key switches to make the are off supply small - but that's just an opinion

Regards

Owen

[Tom Sutton]

There appears to be two ways of wiring the test switch in EL systems,

1.   The normal lighting is switched off and the escape lighting comes on.
2.   The escape lighting circuit is switched off and the normal lighting remains on.

The current BS 5266 Pt 1 2011 states, a test facility should simulate a main failure and not interrupt the normal lighting supply so  type 2 is the current system to use.

However the guy above has the both systems in his premises should he update the system to the current standard? I believe providing he has no problems in implementing his tests then I see no reason to update unless they refurbish or if required due to faulty equipment.

[colin todd]

Tam that was how it was always meant to work.