SAFETY QUESTION

[hawkeye23]

Can someone explain please the proceedure to work at opening electrical panels loadcenters . disconnects , motor control centers where there will not be any hands on work just inspections, all of the above will be energized . Do you have to turn power off first or is wearing ppe the answer to the safety questions?
Not turning power off is just because it will be inconveint to the process . There is or can be a time of the day where the power can be turned off.

 

[jxofaltrds]

To many variables.

NFPA 70E: Standard for Electrical Safety in the Workplace?

http://www.nfpa.org/aboutthecodes/AboutTheCodes.asp?DocNum=70E&cookie_test=1

 

[vey]

I'm kind of new to this, so I am sure that I won't get this just right.

Rather than just throwing you a link, I'll try and get you started:
1. NFPA 70E covers voltage under 600 volts.
2. According to the NFPA 70E, the best way to do any work, even inspection work, is to work on de-energized equipment -- keeping that in mind, there is no law that says you can't work at 2 AM or on a Sunday if you have to.
3. If you must work on energized equipment, there are two major dangers -- electrocution and arc flash
4. If a special arc flash study has not been done (not likely), then there are tables in NFPA 70E that will give some guidance. The tables consider voltage, type of work done, including removing panels and testing voltage, inspections etc. I think there is over 100 tasks listed.
5. The tables will tell you how dangerous the work is and what equipment should be worn.

The tables are too extensive for people to answer your questions here, so looking at them yourself is your best bet. There are books that break down the standard into an easier to read format. Ugly's is one of them, but I don't think they have a 2012 version published yet.

You could also take a course and I think there are on-line courses on this now.

 

[iwire]

Nice job vey.

I will make two points I consider important.

1) You are never to be exposed to live parts without PPE.

If you need to open a live panel you need to suit up.

2) Just because you do suit up does not mean you can do any live work you want to.

You are pretty much limited to inspection and troubleshooting.

Repairs and additions should be done dead unless the employer can demonstrate the risk of a shutdown exceeds the risk of doing it live.

Please consider that if something goes wrong you could end up in court explaining the decision and it will be a tough sell.

 

[pfalcon]

3) Qualified person
4) During the inspection you should limit machine operation as much as possible. If this is discrete processing then you should be able to Estop or Feed Hold the machine long enough to inspect.

 

[hawkeye23]

All sounds clear enough to me. thank you .