Control Panel Power Identification

[electech]

I work as a Technician for a large company. We have a large manufacturing building nearing completion. The building contains about 7 Motor Control Centers and 20 or more lighting and power panels. My concern is none of the equipment is marked as to where it is feed from, (panel & breaker or motor control center & bucket). It is not marked on the equipment control panels. There is no identification on the 120, 240 or 480 wiring feeding power to the control panels. There are naming differences on the physical equipment markings and what is on the wiring drawings.

The general contractor and electrical sub-contractor involved has clearly stated there is no code requirement other than to label at the power source, (motor control center or power panel) and no identification of the power feed wires is required.

From a safety aspect, there is no way to identify the power source feeding a control panel or piece of equipment except for wiring drawings which will be kept in another building. This assumes that the electricians and apprentices installed everything by the prints and knew what each piece of equipment was. To date, equipment has been damaged when an electrician hooked up 480/3 phase to a 120 control panel by mistake. The control panel was clearly labeled as to voltage requirements.

Is there any help in the codes for requiring power source identification at control panels or equipment?

Thank you!

 

[petersonra]

Re: Control Panel Power Identification

There are OSHA lockout/tagout requirements where you MUST identify ALL sources of energy and where to lockout that source of energy.

This is generally not in the scope of the EC but rather the GC or the end user because it covers all sources of energy not just electrical.

I would be extremely nervous about a set of drawings that had nomenclature differences between them. Normally, an end user would hold back a certain part of payment (typically 10%) until drawings are submitted representing the final "as-installed" state of all the equipment.

I am also nervous about any electrician who would make the mistake of hooking up 120V to what should be a 480V input. Most control panels use different colors to denote 120V versus 480V power and if they managed to not notice this, I'd wonder what else they missed.

Pipe and wire electricians are notoriously awful at even reading control panel schematics and you may wish to check what they did. They are also notorious for not wanting to spend the time marking the wires, because it adds a fair amount of time to the install, but down the road its a major hassle for the end user.

Best bet is to get a guy familiar with panel wiring and reading schematics to work with them the rest of the way through and spot check what they are doing to make sure they understand what they are supposed to be doing and actually do it.

If your specs did not insist on proper wire marking, you may well have to accept this. Well written specs cover this situation.

[ October 30, 2004, 02:42 PM: Message edited by: petersonra ]