NEC 2011 Arc flash and Who is Responsible for the label marking

[mjcondon5]

Hi, here is what I have, I am a system integrator who is building a 480VAC, UL508a control panel. I am suppling a Arc Flash Label (one that can be filled out) on the front door of the control panel. I then ship my control panel to my customer, who then packages it with his equipment. My customer then hires a contractor to install the panel and equipment at the end customers site.

Now, who fills out the arc flash label that I placed on my control panel.
I always read it, per the NEC, as the employer (ie the end owner of the machine) would fill this out the arc flash label.
Now, I have an "end owner" who is insisting that I am reading the NEC incorrectly.
He believes that the manufactor of the equipment should, who in turn, believes that me as the manufacturer of the control panel should fill it out.

So, who fills out the arc flash label and under what article.
the manufacturer of the control panel,
the manufacturer the equipment,
the installer,
the end owner.

Thanks in advance.
MikeC:

 

[iwire]

How would you know the fault current at the installed location?

In my opinion it is impossible for you to fill it out.

 

[don_resqcapt19]

The NEC does not actually require a detailed arc-flash label. 110.16 requires that the control panel have a generic field installed "arc-flash hazard warning" label.

You are required to provide a "short circuit current rating" label on your panel. 409.22

There are rules in NFPA 70E that will require more detailed arc-flash labels, but to provide that detail, you need an engineering study of the power supply system. This is not something that the supplier of a control panel would normally do.

 

[jim dungar]

The NEC does not actually require a detailed arc-flash label. 110.16 requires that the control panel have a generic field installed "arc-flash hazard warning" label.

You are required to provide a "short circuit current rating" label on your panel. 409.22

There are rules in NFPA 70E that will require more detailed arc-flash labels, but to provide that detail, you need an engineering study of the power supply system. This is not something that the supplier of a control panel would normally do.

Note the key wording in NEC 110.16, the label needs to be field installed.

NFPA70E 130.5(C) contains similar wording, field marked, which is probably more in line with your position.

 

[don_resqcapt19]

Note the key wording in NEC 110.16, the label needs to be field installed. ...

There is no real reason why this label has to be field installed other than the code wording.

The original propoal for this rule would have required specific arc-flash information like 70E does and that would have required a field installed or marked label. The requirement for this specific information was removed at the comment stage, but the requirement for the label to be field installed was not removed.

 

[jim dungar]

There is no real reason why this label has to be field installed other than the code wording.

The NFPA70 wording is consistent with that of NFPA70E in requiring 'field labeling'. What is different is that the NEC, the installation code, does not address the label content, which is left to the 'operation code' instead.

It is not possible for the manufacturer of equipment to determine arc flash boundaries without knowledge of the specific field installation.

 

[petersonra]

We occasionally get customers or potential customers who wants us to tell them how much short circuit current they need.

We have customers that tell us what the SCCR of the panels have to be and others that do not specify it. The ones that do not specify it usually get 5 or 10 kA, depending on the components used if it is CBs. If it is fused the sky is the limit.

I don't know if it is just us and our customers, but we are getting more and more orders where the customers will not accept fuses. It makes it a little more expensive to get higher SCCR.

 

[don_resqcapt19]

The NFPA70 wording is consistent with that of NFPA70E in requiring 'field labeling'. What is different is that the NEC, the installation code, does not address the label content, which is left to the 'operation code' instead.
It is not possible for the manufacturer of equipment to determine arc flash boundaries without knowledge of the specific field installation.

But there is still no real reason why the generic warning label required by the NEC has to be field applied. Since the required label is generic and not specific, it could be applied to the cover by the equipment manufacturer and would do the same job as a field applied label.

NFPA 70E is not normally an adopted code and not enforced by the electrical inspector, NFPA 70 is. Only the label required by NFPA 70E requires knowledge of the specific field installation.

 

[jim dungar]

But there is still no real reason why the generic warning label required by the NEC has to be field applied.

That is true.

What really bothers me is when I see a panelboard with a manufacturer's label mentioning the Danger of arc flash, a contractor's generic arc flash Caution label, and the facilities NFPA70E compliant Warning label.