What Are The Actual Rules Regarding Panelboard Line Side De-energization?

[yesterlectric]

There’s a difference of opinion regarding what should be required/allowed for proper isolation for deenergized work. The situation involves replacing a feeder breaker in a panelboard in a circumstance where due to choices in design, a complete outage on the entirety of the panelboard requires shut down of the customer owned substation and all customer loads. I have a couple of questions:

1. If these panelboards have line side “barriers” (which are really just a form of insulation and sometimes imperfect at that ) as required by NEC section 230.62 and 215.15, is it nolonger considered “energized electrical work” to just open and lock the main breaker, test, and then remove the covers to do the work on the load side?
2. Has OSHA ruled or issued any opinions on whether it’s considered infeasible to expect the line side of the panelboard to be the energized for work on it slow side? In most cases where this scenario comes up, it’s the fact that you have to get the utility out to deenergize. In this case, it’s the fact that due to choices in design, the customer has to experience a complete substation outage.

I hate to be picky about the response, but being that it’s a matter of differing opinions, any authoritative sources that can be provided along with any statements made would be helpful.

 

[jim dungar]

This is not an NEC issue.
The specific work procedures and practices are between your employer and their insurance company. The legal system will likely become involved when an incident occurs. When you go to court you will be expected to defend why you did not follow industry accepted standards such as NFPA70E and OSHA

Why not take the outage and modify the system so this situation is avoided in the future?

 

[infinity]

If the line side is protected by barriers then what is the issue? Would someone expect the POCO to come out and pull the meter if you wanted to remove the panel cover? The protection of the metal parts of the line side of the service disconnect should be enough to keep any qualified individual working on the panel safe.

 

[hillbilly1]

As far as OSHA is concerned, those little barriers do not remove the requirement for full PPE because live conductors are still exposed. As far as tasks like changing out breakers on a dead bus, would not be considered live work, but would not negate the PPE requirement.

 

[D. Castor]

As long as there are exposed live parts, whatever the PPE requirement is for that panel, based on the arc-flash hazard analysis, would still apply, IMO. You might want to check out the applicable section in NFPA 70E. And yes, NFPA 70E is not a legal requirement, but OSHA uses it to determine what is the standard of care in the industry.

The basic rule in NFPA 70E is that energized work is not allowed except for three specific situations and it's unlikely that this work would fall under those three exceptions.

 

[ModbusMan]

Why not take the outage and modify the system so this situation is avoided in the future?

This. If I were writing the MOP...
1. Shut it all down, LOTO style.
2. Install a disconnect just ahead of the panel you're dealing with.
3. Leave the new disconnect open and locked out while re-energizing the substation.
4. Replace the feeder breaker, close the newly installed disconnect, then the breaker.

Satisfies the safety requirements NFPA/OSHA may expect you to follow, minimizes unrelated downtime for the rest of campus, and makes it a lot easier for whoever follows you to perform subsequent work.