ECN Forum
Posted By: SJT Emergency Circuit breaker panels - 04/11/12 02:00 AM
Are any circuit breaker panels supposed to have a unique marking on them, to identify them from a normal power panel?
I'm talking in an industrial setting, where you have a lot of panels. The panel that is backed up with the generator, from a transfer switch.
Is it up to the electrician to identify them with a stripe on the panel? Any code rules (NEC,OSHA) about that?
Thanks - SJT
Posted By: HotLine1 Re: Emergency Circuit breaker panels - 04/11/12 03:29 AM
Usual markings are determined by the engineer/design professional, and are part of the job 'spec'. That said, it varies by the scope of the job, the available power sources/voltages, etc.
The actual 'labels' are usually installed by the EC, along with the panel circuit directories.

As to 'code'; there are some requirements, ie: 'red leg' or ''high leg'; Fault current, Article 690 & 705, etc.

From the varied jobs I do plan review on, the PE/EE/Arch have panel ID spec'd out. A large data center has panel designations that would make your head spin!!

Scott35 may have some input on this.
Posted By: mikethebull Re: Emergency Circuit breaker panels - 07/01/12 03:55 PM
700.10 (A) All boxes & enclosures (including transfer switches , generators & power panels) for emergency circuits shall be permanantly marked so they will be readily identified as a component of an emergengy circuit or system.
Posted By: HotLine1 Re: Emergency Circuit breaker panels - 07/02/12 12:51 AM
Mikethebull:

Careful reading of the specific location of the genset, and WHY it is being installed has to be considered.

Article 700, 701 & 702 have to be reviewed, with 700 and 701 being the most stringent, as one is for Emergency systems, and 701 is for Legally Required Systems. 702 is commonly used for gensets at comm and industrial facilities for 'backup power'. Often, it is inadvertantly called "Emergency", but does not meet the requirements of 700.

The 'marking' for Optional are 702.7 (a)&(b).

A typical 'large' 702 genset may have two panels with chosen circuits, panels being marked 'Generator Panel'; 'Critical Circuit Panel', etc.

What things are labeled or called may or may not be what they are within the NEC definitions or intent.

700.2 from 2011 NEC:
Emergency Systems. Those systems legally required and
classed as emergency by municipal, state, federal, or other
codes, or by any governmental agency having jurisdiction.
These systems are intended to automatically supply illumination,
power, or both, to designated areas and equipment
in the event of failure of the normal supply or in the event
of accident to elements of a system intended to supply,
distribute, and control power and illumination essential for
safety to human life.
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