Disconnect and molded case CB

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cornbread

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110.16 Flash Protection. Switchboards, panelboards, industrial control panels, and motor control centers in other than dwelling occupancies that are likely to require examination, adjustment, servicing, or maintenance while energized, shall be field marked to warn qualified persons of potential electric arc flash hazards.

Are disconnects and molded case cb's exempt from having lables?
 

charlie b

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They are not on the list, so I would say yes. The 2008 edition added words at the begining, "Electrical equipment such as. . . ." I don't think a breaker or disconnect would be included in the "such as" statement.
 

zog

Senior Member
Location
Charlotte, NC
They are not on the list, so I would say yes. The 2008 edition added words at the begining, "Electrical equipment such as. . . ." I don't think a breaker or disconnect would be included in the "such as" statement.

I beg to differ, breakers and disconnects should be included in the study and labeled. The 70E requires either the Ei or the HRC to be added to the label.
 

cornbread

Senior Member
Zog I think you are right but where in 70E is this required? Is it the lable definition in art. 100?

I have folks quoting 110.16 and saying not needed.
 

rbalex

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Mission Viejo, CA
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I agree with Zog.

A single disconnect/overcurrent (and otherwise legally used) device falls within both the NEC and 70E definition of a switchboard. (Art 100 in both documents)

This is further emphasized in 70E [2009] Art 210 where Disconnect Switches are specifically listed along with the other classes of equipment.
 

cornbread

Senior Member
I was thinkng the same thing, I'm trying to explain it to our staff that the labels are installed for the electricians and not for OSHA. We are have a debate here about the verbage in NEC 110.16, I have several folks trying to say disconnects are not covered. I have a feeling I'm not going to be very popular for the next few weeks.
 

raider1

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Logan, Utah
I was thinkng the same thing, I'm trying to explain it to our staff that the labels are installed for the electricians and not for OSHA. We are have a debate here about the verbage in NEC 110.16, I have several folks trying to say disconnects are not covered. I have a feeling I'm not going to be very popular for the next few weeks.

With the addition of "Electrical equipment, such as......" to 110.16, I think it makes it much easier to include disconnects in the requirements of 110.16.

Chris
 

cornbread

Senior Member
I agree with common sense but now its my electrcial crew leader that is having problems with putting labels on 480V disconnects. I think it has to do more with NFPA70E overload.
 

barrusr

Member
I disagree. disconnects have interlocks to prevent them from being opened energized, hence not likely to be serviced energized. Line side has barriers to prevent accidental contact.


Russ
 

zog

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Location
Charlotte, NC
I disagree. disconnects have interlocks to prevent them from being opened energized, hence not likely to be serviced energized. Line side has barriers to prevent accidental contact.


Russ

Again, look at the definition of an arc flash hazard, it is not just working inside the disconnect, it is also operating it.
 

jim dungar

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I disagree. disconnects have interlocks to prevent them from being opened energized, hence not likely to be serviced energized. Line side has barriers to prevent accidental contact.


Russ
Turning off the disconnect (regardless of door interlock) is not sufficient for saying the switch is de-energized. The disconnect is considered energized until it has been verified/tested with a meter, which requires appropriate PPE

The only way to consider the disconnect as de-energized would be to open its feeding device instead.
 

Jraef

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Turning off the disconnect (regardless of door interlock) is not sufficient for saying the switch is de-energized. The disconnect is considered energized until it has been verified/tested with a meter, which requires appropriate PPE

The only way to consider the disconnect as de-energized would be to open its feeding device instead.
These things qualify...
check_volt_panel.jpg

Grace CheckVolt link
 

zog

Senior Member
Location
Charlotte, NC
These things qualify...
check_volt_panel.jpg

Grace CheckVolt link

Those are nice, I have seen similar products on the market that used lights and they were not deemed acceptable by OSHA in a few cases and dissapeared quickly because there was no way to do the L-D-L check. I think this one might be acceptable but would be interested to see what groups like the 70E commite and OSHA say abou them.

Looks good to me though and I am a known safety nazi.
 

jim dungar

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These things qualify...
Yes, they appear to let you perform the verify/test function I mentioned.

The problem with 'neat' practical things like this, is there is almost no way to know if they actually are 'acceptable to OSHA' until a lawsuit is settled.
 

Jraef

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Location
San Francisco Bay Area, CA, USA
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Yes, they appear to let you perform the verify/test function I mentioned.

The problem with 'neat' practical things like this, is there is almost no way to know if they actually are 'acceptable to OSHA' until a lawsuit is settled.
They promote them as such, I'll have to ask for more details next time the guy is in here. But you're right, I don't think OSHA really "approves" anything up front, they just point fingers after the fact.
 
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