Confused about exposed live parts

[GScollins]

I am having trouble figuring out what permits, etc., are required for certain tasks. Our safety person thinks that I need to call out utility company and shut off all power coming into the boxes since there are still hot wires in the top of the box.

Example 1 would be terminating new branch circuit conductors on breakers in a main breaker panel with the main breaker turned off and bolted covers removed. Is this example going to require a energized work permit?

Example 2 would be terminating the same new branch circuit conductors to breakers(off) with main breaker on and buss exposed with bolted covers removed and some other breakers turned on.

Neither example would be working on energized parts, but would be near energized parts.

Example 3 would be changing fuses or landing load wires in a 100 amp 480 volt disconnect with line side still energized, disconnect off, arc shields still in place

I assume all 3 would require wearing proper level of arc flash suit. But I get confused about LOTO and energized electrical work permits.

Does any of this make sense? And how do you approach this?

thanks

 

[Dennis Alwon]

IMO, both examples are live and would require proper gear however it is rarely done. Unfortunately with the design of panels in the US turning the main breaker off may help with safety but it does not eliminate all the risks as the wire and lugs on the breaker are still live.

 

[GScollins]

Thanks for the reply. I still have question because at work, they will not let us work on energized parts. Calling out the utility company is very hard to do, just to completely kill a panel or disconnect so we can work in it. Also it can take an act of congress to get a Down Time Request to shut down a whole station.

Troubleshooting is ok, such as voltage test, etc. while wearing appropriate arc flash gear. But changing a fuse or landing a wire is not troubleshooting.



thanks again

 

[GScollins]

To clarify my question is:

To comply with safety rules of no live work, does the line side of a disconnect or panel need to be off before I can change a fuse or land wires in a panel or disconnect?

 

[Dennis Alwon]

To clarify my question is:

To comply with safety rules of no live work, does the line side of a disconnect or panel need to be off before I can change a fuse or land wires in a panel or disconnect?

I believe that OSHA would require the disconnect to be off but I don't think the line side would need to be de-energized. Generally it is not done. Maybe someone else knows more on this

 

[jim dungar]

...To comply with safety rules of no live work, does the line side of a disconnect or panel need to be off before I can change a fuse or land wires in a panel or disconnect?

There is no single set of rules/laws/codes you can go to for a definitive answer.

OSHA requires you to be safe when you are working - wear the require PPE and follow established procedures.
NFPA 70E contains industry accepted standards including methods for determining PPE.

So, it is up to your company to establish its own Electrical Safe Work Practices program based on its acceptable level of risk versus task and its desire to argue those practices in front of a court of law.

 

[rlundsrud]

cpr requirement

cpr requirement

It is also a little know fact that if a person is working around live parts, they must be certified in CPR according to NFPA 2009 70e. As the previous posts mentioned this is also something that is almost never done. In fact few of the older electricians that I have know even wear PPE, which is also a must. I just thought I would pass that along.

Bob

 

[petersonra]

I assume all 3 would require wearing proper level of arc flash suit.

None of the scenarios you mention are actually allowed to be performed with the equipment energized so the actual answer is that you will need no PPE at all electrically.

You might be able to come up with some contrived situation where you can do this stuff live, but they would be far and few between.

 

[GScollins]

None of the scenarios you mention are actually allowed to be performed with the equipment energized.

I wish that I could find something that documents that.

 

[petersonra]

I wish that I could find something that documents that.

Read what NFPA 70e says about when live is allowed. Very limited.

 

[jim dungar]

I wish that I could find something that documents that.

You won't find any.

What your company allows is probably different than what another company allows. There have not been enough lawsuits to actully set industry wide precedences. There are many companies that allow work in equipment that still has voltage on the line terminals (such as changing fuses). I do not know of any manufacturer that does not include instructions that say the equipment should be de-energized before working on it.

As long as you stay the proper distance away, or shielding exists, you are not working on live conductors and therefore not exposed to potential electrical shocks, but it is very common for the arc flash boundaries to extend well past the shock boundary so about the only PPE reduction you might find deals with the 'rubber gloves'.

 

[Fulthrotl]

Read what NFPA 70e says about when live is allowed. Very limited.

the rule of thumb is that hot work is not permitted unless it's more
dangerous with the power OFF. (shutting down a process in a refinery, etc.)

inconvenient doesn't matter. difficult to obtain outages doesn't matter.

if you direct a worker to perform work live, and something goes south,
you are toast. that is really the only rule.

 

[GScollins]

Thank you all for your input. I have requested that we get a disconnect in front of a new panel that is going in on a new project. It was drawn to tie in to the line side of the other disconnect that feeds the load center on the rest of the process. Without a disconnect, the new load center would in effect be fed directly from the lugs of the POCO 750 transformer with the only way to kill it being the cutouts on the pole. We would not be able to pull and terminate the new circuit feeders into it without shutting down the whole facility.

Back in the day, we just stood on plywood and did it. Can't do that now.

thanks again.

 

[kwired]

If it is determined that the equipment is energized when all that is truly energized is the incoming line conductors, and you are having issues with not wanting to shut off certain equipment for many consider simple maintenance procedures, then maybe some careful redesigning needs to be done so that you do not have to shut off so much equipment in certain instances, just to work on a particular item. At very least do not have unassociated loads fed from same panel, that way you are not effecting multiple work lines when you do have to shut something down. Example - don't put pre-treatment process line loads in the same panelboard that supplies a mid process or a finishing process line. That way if you need to work on something in the pre-treatment line at least all you will shut down is the pre-treatment line, and the others can continue to run.

 

[petersonra]

I am a big fan of putting CB panels out where the equipment is to serve as power distribution points. They also serve well as disconnecting means for equipment in that area. I have never liked having the only disconnecting means to a control panel be in a locked room on the other end of the plant.

Some of our customers have even stopped putting disconnecting means into the control panel in favor of having it external so the panel can be completely de-energized.

 

[GScollins]

Example - don't put pre-treatment process line loads in the same panelboard that supplies a mid process or a finishing process line. That way if you need to work on something in the pre-treatment line at least all you will shut down is the pre-treatment line, and the others can continue to run.

That is exactly the point. I don't want to shut down a 500hp softstart, 2-125 hp pumps, and the whole station just to work on some circuits to a few new valves. Third party engineers designed a new main breaker sub panel to be tied into the line side of the rack without a disconnect. Turning off the main breaker shuts off the new circuits, but I can't work in that panel with line side energized. I made a call this morning to request a change, contractors are working 7-12s to complete a fast track project. Engineers are going to hate me.

 

[kwired]

That is exactly the point. I don't want to shut down a 500hp softstart, 2-125 hp pumps, and the whole station just to work on some circuits to a few new valves. Third party engineers designed a new main breaker sub panel to be tied into the line side of the rack without a disconnect. Turning off the main breaker shuts off the new circuits, but I can't work in that panel with line side energized. I made a call this morning to request a change, contractors are working 7-12s to complete a fast track project. Engineers are going to hate me.

Someone needs to inform the engineers of the safe work requirements that will apply at this location and tell them to design with those requirements in mind. Then the owners, managers, engineers, safety people, and mechanics all need to be on the same page and in agreement with the best method that satisfies all of them - or at least has the best compromise between all of them.

 

[J.P.]

I read post like these and realize I live in the wild west. Nobody around here has even heard of the word safety, unless your not tied off on your six foot ladder or wearing safety glasses.

We'll turn off power when we can but most of the time everything gets worked hot.

 

[kwired]

I read post like these and realize I live in the wild west. Nobody around here has even heard of the word safety, unless your not tied off on your six foot ladder or wearing safety glasses.

We'll turn off power when we can but most of the time everything gets worked hot.

I think there are more people in your boat than you realize, or maybe on your wild west ranch would be a better analogy The larger employers are the ones that have the more complex safety programs and is where you are seeing most of the attempt to comply with OSHA to the fullest extent possible. There are smaller employers that do a fair job, but there is so much out there it is hard to cover every possibility, and takes lot of resources to keep up with everything.

Forget electrical safety for a moment, and look at all other small workplaces safety programs and you are likely to find holes in their practices, then throw in electrical related problems that they do normally encounter and they have no idea they even are in violation of any OSHA rules, even when they are trying hard to comply.

 

[GScollins]

The change order was accepted to put a non fused disconnect between the load center and the source. A de-energized panel is a happy panel. We can work in it safely without cat 4 gear the whole time now. Thanks for the input.