commercail lighting

spintronic73 · Apr 11, 2011

ive got lighting job at a workshop with bay lighting florescent the owner wants better lighting so i was thinking about replacing them with sodium lighting and where his florescents was giving out 200 watts, i i would get 400 watts sodiums problem is he wants test certificate but 3 phase board is old 25-30 years would i need to put rcd consumer unit as i am useing all old trunking,conduit and 9 gang switch

Paul.M · Apr 11, 2011

You don't need to put the circuit on an rcd in a commercial building unless requested by the client.

malcolmsanford · Apr 11, 2011

Simple answer is no you would not need to fit an RCD unless you needed it for additional protection.

It would seem that the installation is run in trunking/conduit and so would not need to be protected under regulation 526.6.6 or 526.6.7.

The only thing you will need to do is to make sure that the protection device will operate in the given time so your Zs will need to be done and calculated. Obviously Zs exceeds the sated time, then RCD protection can be fitted to counter this.

Just a piece of advise, you may find that the protection device be it fuse or MCB on an installation that old, may have been changed, and perhaps the original lighting circuit was designed as a B type MCB or a G type fuse and has been changed to C or M respectfully, so make sure your Zs is spot on.

Also make sure if that trunking/conduit is being used as the CPC, and I would expect it is on an installation that old, unless it's been rewired to fit CPC. You should check really the continuity of the installation using a ductor tester, but to confirm continuity you can do R2 with a wander lead, and your Zs test will confirm that you have a good EFLI path.