Faulty mains failure generator.

[Tom Sutton]

The emergency lighting has failed due to faulty mains failure generator. The installation is 20 plus years old but functional. Can you replace the generator with new without up dating the whole system?

[kurnal]

The usual answer Tom, fire risk assessment! What is the building used for, by whom and when, what is the coverage of the old system, is it sustained, maintained or non maintained, if the latter is it sensitive to sub circuit failure, are the levels of illumination adequate, are points of emphasis adequately covered , will the run up time be acceptable etc.

[nearlythere]

Sounds more like standby lighting than emergency lighting Tom.

[Tom Sutton]

Thanks guys and I have got back to him to establish if it is standby lighting or emergency escape lighting or both.

If you check the BS 5266-1:1999 it accepts batteries and generators for emergency escape lighting but in the 2005/2011 versions they do not mention it, only certain aspects like servicing for instance. Therefore are generators acceptable for emergency escape lighting or should it be only used for standby lighting? Also if they were installed years ago can you say they are not now acceptable for emergency escape lighting?

[nearlythere]

Thanks guys and I have got back to him to establish if it is standby lighting or emergency escape lighting or both.

If you check the BS 5266-1:1999 it accepts batteries and generators for emergency escape lighting but in the 2005/2011 versions they do not mention it, only certain aspects like servicing for instance. Therefore are generators acceptable for emergency escape lighting or should it be only used for standby lighting? Also if they were installed years ago can you say they are not now acceptable for emergency escape lighting?

Not very many generators installed which will provide sub circuit failure back up which is what you need for EL.
The existence of an emergency generator may allow standby lighting to be used, but it is not necessarily adequate for escape lighting.  The generator will only start on total power failure.  This is not the most likely result of fire, which is more likely to affect only a limited number of circuits.  Unless the generator supplies dedicated luminaires that are wired in fire resisting cable, it is unlikely to be adequate for the provision of escape lighting.

[AnthonyB]

Not withstanding the extensive costs of correctly servicing & maintaining the generator (on top of the lighting testing) reasons at some sites I've been to are that:
a) local failure doesn't kick in the generator
b) changeover times are too slow, not meeting BS5266 requirements

Most sites have phased in self contained fittings and where generators are retained it's usually for non statutory standby/business continuity purposes on top of the 3 hour internal batteries in EL fittings.

A new generator will cost a fortune, especially with the logistics of removing the old one and installing the new (as many aren't in the best locations for access) and personally I'd rather focus the capital spend on self contained fittings/conversion kits.

[colin todd]

Almost here, that almost sounded like a quotation in your posting?

[nearlythere]

Almost here, that almost sounded like a quotation in your posting?

It was almost Dot. Why have a dog and bark yourself?