This article starts out by saying "Electrical equipment such as switchboards, panelboards, industrial control panels, meter socket enclosures, and motor control centers that are in other than dwelling units and that are likely to require examination, adjustment, servicing, or maintenance while energized shall be field-marked with a label...."

So the equipment mentioned above seems to be equipment where on may open it for something, maybe IR or in industrial panels, troubleshooting or performing work on a PLC while there is live exposed 480V, for example.

However, what about local disconnects where they are operated to LOTO a piece of equipment? If one does a risk assessment on the switch, (properly installed, maintained, all covers closed, no sign of impending failure) no AR PPE is needed. So is a label needed?

Just thought it might be an interesting discussion.

I've spent time thinking about this very thing. My view is that there is virtually no chance of someone opening a local disconnect energized; it is not likely to need examination, adjustment, servicing, or maintenance with the power on. Additionally, for everywhere I've worked, at least, the incident energy present at the local disconnect level is essentially zero.

However, our corporate safety department has taken the position that all local disconnects need to be labeled, so I will be labeling all local disconnects. I'm not making it a very high priority though.

I would say a disconnect is very likely to require examination, ... while presumed to be energized. Examination for a visibly open condition may be required as part of the LOTO procedure.

Your very argument against the label states the disconnect is well maintained. That maintenance requires labeling per the section quoted.

Even if the power is turned off at a location upstream, the disconnect must be considered energized until testing proves otherwise before any de-energized maintenance can occur. This testing on a presumed live disconnect meets the labeling requirement. I also find that thermography works better with the device energized.

If we have an MCC bucket that we turn off, verify zero energy on the motor leads coming out of the bucket, I also have to verify zero energy at a downstream disconnect if I want to remove the coupling on the motor? A lot of troubleshooting involves control circuits and therefore is performed at the MCC. In my experience motor local disconnects are not a location that is "likely to require examination, adjustment, servicing, or maintenance while energized." So to answer the original question, based on the work practices I usually observe, I would not label the motor disconnect.

He did have a good point that the one case of thermography would require the disconnect to be opened while energized.

If we have an MCC bucket that we turn off, verify zero energy on the motor leads coming out of the bucket, I also have to verify zero energy at a downstream disconnect if I want to remove the coupling on the motor? [/quote]

The control of hazardous mechanical energy is outside my expertise, and I believe is off topic for this discussion. I am speaking of maintaining the disconnect itself. NETA has a list of maintenance procedures to be performed on this device on various schedules depending on its criticality.

Are folks really trying to save the cost of a label here?

It's not the cost of a label. It's the cost to study hundreds of disconnects, then create or order hundreds of labels, then have people place those hundreds of labels on the local disconnects. In many cases local disconnects won't handle standard size labels, so then you have to specially create smaller labels to fit the disconnect.

And, in my case, you find that most of them have an incident energy statistically equal to zero, and even those with some energy are a fraction of the value that triggers the need to use any arc flash PPE at all. So instead of just being able to tell your workforce that these is no arc flash risk with local disconnects, you instead have to go through the above process to create and apply the labels.

So the assumption is that the drwing is never wrong, and you are positive that mcc bucket"x" feeds motor "x", and hence that you never need to verify that there is 0 voltage at the motor diconnect?
[ Sure if the MCC constantly cycles that motor you are probably correct, but what about the motor that has run continuiously for 10 years]
Are you sure that:
You will never open it for an IR inspection?
You will never open it to get the fuse information (assuming it is a fused disc)
Some one, working on the multi motor load it feeds, will never want to verify that the voltages are correct at that point?

Then what was the reason a disconnect switch was installed in the first place?

Yes, I will agree that MOST disconnects will have small arc flash values. What about the disconnect for a 200HP blower, or a large chiller?

If you don't label a location, how does the person working on it KNOW that it was "ignored" in the labeling "on purpose", rather than by accident?

In my experience the drawings are right, but the wiring can be wrong.

A couple points:

1. I assume that you would require motor connection boxes be labeled if there is no local disconnect, as all your arguments for the local disconnect could also be made for the motor itself.

2. The local disconnects I am working with at my facility are all fuseless/breakerless, which reduces the need to do thermography, and they are not currently included in our thermography program.

Don't forget that the NEC requirement hinges on "frequent" exposure for maintenance. There's no reason to label something that doesn't see frequent exposure with energized circuits would need a label at all. This would extend even into items that NEC lists. For instance some underground switchgear is specificaly designed for effectively "zero" maintenance. It gets tested on a very long test cycle (perhaps once every 5-8 years) but there are no user serviceable parts. "Servicing" other than testing means replacement. The energized parts that would be exposed are either other breakers/switches (again, sealed), or elbow connectors that are load break rated. Granted this gear is primarily intended for utility (ANSI/NESC) locations but it can and is used successfully in industrial settings.

To me other than the argument that the label requirement should have an exception when the equipment rating is below the minimum threshold for site work wear policies, the frequency argument means that for equipment that simply does not or should not see much in terms of any maintenance while energized means that at that point the person doing the work should consult the arc flash study for the site and/or engineer maintaining it.

Taking the argument that labels are not required only for equipment that is NEVER serviced while energized becomes absurd because it then requires labels on every junction box, motor termination enclosure, conduit, cable tray, receptacle box, etc., because eventually at some point all equipment will require some kind of servicing or maintenance activity, even if it is to remove the burned up parts and replace it with fresh ones.