Available Fault Current

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Newbee

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Is it required of the NEC to indicate the " available fault current" at the main service and at other points in the electrical infrastructure?

For example at the main 1200 amp service, at all sub panels, lighting control panels, lighting control disconnects, motor control centers...etc etc etc

And if so, who is responsible for this, and in what "manner" is it to be done?

Thanks

Newbee

[ February 25, 2006, 09:59 AM: Message edited by: Newbee ]
 
Re: Available Fault Current

If you are asking if it is required to mark equipment with this type of info, no it is not required. That is because the available fault current is always subject to change, and marking the equipment could actually be a dangerous thing if it is not accurate.
 
Re: Available Fault Current

Thank you. Is it required by any other code ?

NFPA 70 ?

I've looked into the calculations, and wow....Looks like even engineer would have some difficulty.

Newbee

[ February 25, 2006, 11:46 AM: Message edited by: Newbee ]
 
Re: Available Fault Current

All you are required to do is field mark the specified equipment in Section 110.16 to warn of potential arc flash hazards.
 
Re: Available Fault Current

Can you expand on " field mark" ? Are you talking about stickers or tags ? What exactly are they required to say? Is there a specific verbage that is required?

Thanks

Newbee
 
Re: Available Fault Current

Newbee,
There is no code required definition of field marked. 110.16 just says "to warn qualified persons of potential electric arc flash hazards". You could write it with a magic marker. Many folks voluntarily use ANSI Z535.4-1998 for signage guidance.

NFPA 70E has some requirements for equipment marking, but this is a standard only and not a code. NFPA 70E is generally only enforced by OSHA after an accident. :(
 
Re: Available Fault Current

There is a FPN note to the ANSI sign standard.
Danger High Voltage, or Danger ARC Flash is not the correct wording.
A sign has three parts
The icon
The warning or danger
What happens if you don't comply.
The colors have to be correct, IE danger is red.

Danger High Voltage means nothing.
 
Re: Available Fault Current

Tom,
Since it is a FPN, the ANSI document would seem to be a recommendation not a requirement.
Following the ANSI document may make it easier to defend in court if there was an incident, but is it required?
 
Re: Available Fault Current

There are absolutely no requirements in NFPA70 or NFPA70E that spell out any all rules for advisory labels. Except for, NEC 110.16 which simply says a label is required.

Personally any label I used would meet the requirements of ANSI Z535.4-1998. But even this does not say:
How many labels are needed,
Where the labels should be put,
What the labels should say,
What size the labels should be,
How permanent the labels need to be.

The ANSI standard does say:
WARNING means a result may happen. Warning labels must be "orange".
DANGER means a result will happen. Dnager labels must be "red".
 
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