Emergency Lighting

[Luke1]

Hey,

Cant really get my head around emergency light. I get theres maintain and non-maintained but not all that sure how there wired.

Any one have any sites they know which might help out?

Cheers

 

[sparky40]

Hello Luke,
On sites where I have worked,
Maintained = Always on.
Non Maintained = Off/Switched.
I'm sure later posts will elaborate or correct me if I'm wrong.

Are you interested in the wiring etc of commercial/industrial set up's with fluorescent lighting/ key switching etc, or smaller installations.?

 

[Belle427]

maintained=can be switched between lamp on at all times or on with supply failure only
non maintained=on after mains supply failure only

 

[JohnD]

Sustained

(can't remember what it does)

 

[ricicle]

Sustained is a fitting which has at least 2 lamps on in normal mode and 1 of them will remain illuminated at mains failure

 

[RF Lighting]

Ive learnt a new word today!

I guess you mean fittings like 4 tube recessed modular fitting with emergency packs?

 

[ricicle]

Could be

 

[Spark123]

There is also distributed which is where there is a central bank of batteries (and a charger, auto switch or even possibly an inverter) which supply luminaires around the building, this type must be wired in fire resistant cable such as pyro.

 

[Luke1]

Hey, cheers for .

Any chance and one has any diagrams how there wired differently?

 

[Big_Spark]

Luke, Non-maintained fittings are wired in a reasonably standard way, ie: Live/Neutral Pair as a radial (Earth obviously included!!)

Maintained fittings are wired with three core and earth, One core is a permanent live (Usually L1), one core is switched (Usually L2) and one core the neutral.

All types must include test switches (Key switch) and they should be as reasonably close to the fittings as possible, but usually one key switch per room/corridor/stairwell.

For the Inverter based Emergency firrings there is usually a central test switch which is used to simply kill the supply to the charger circuit.

As an example for use..

A light fitting in a room and forming part of the normal lighting circuit would be a maintained type of fitting as it would be switched on with all the usualy lighting, but would energise on the battery pack should the 230V permanent live fail.

A light fitting whose sole purpose is emergency illumination would be a Non-Maintained type, these are usually used over fire exits and on stairwell escape routes. Often they are Illuminated constantly, but several manufacturers also allow for an OFF state so they only illuminate on Power Failure. Depending on the building use, it is highly likely you would find both types in a given building, especially if it is publicly accessible , such as cinema's, Pubs, restaurants etc.

The Inverter type system is old hat now and very rarely installed, they are not very cost efficient in terms of installation and maintenance, but occassionaly they are still put in when the building has special requirements..usually Government ones..

 

[SparkyMarky]

The Inverter type system is old hat now and very rarely installed, they are not very cost efficient in terms of installation and maintenance, but occassionaly they are still put in when the building has special requirements..usually Government ones..

We still prefer to install the inverter type system in our factory when we can. Originally it was a hangover from when we had emergency lighting generators (we took some of the generators out and fitted inverters in their place) but now we prefer it to using maintained / non maintained fittings wired on general lighting circuits. It's easy to maintain and test, and well suited to large factory / warehouse environments. We run all our general lighting from large three phase contactor panels interfaced with the Building Management Systems. Maintained lights would be permanenly on in this situation, and fitting non maintained fittings would mean running an additional live feed to every light bypassing the lighting panels. Horses for courses I guess.....

 

[Big_Spark]

Mark, that is a very good example of where the alternative system works, that was why I only mentioned the economics of the installation and maintenance being the deciding factor.

My personal feeling is that in most commercial installations an inverter system would actually work best, especially for low traffic areas such as dedicated fire escapes, roof areas and the like, where constant lighting is not required, but it is ideal to have as many, if not all, fittings emergencies for when they are required.

With technology being what it is today, there are several ways to achieve it that could be tailored to the individual building and client requirements..

 

[Luke1]

Right, think i get you now.

Cheers for that.