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 Post subject: It was or not safety violation what cost me 5 days of suspension?
PostPosted: Sun Sep 25, 2011 10:15 pm 

Joined: Sun Sep 25, 2011 10:00 pm
Posts: 4
It was or not safety violation?

My task was troubleshooting equipment with SLC 505 controller. In order to plug in the ordinary most common for home and industry PC cable RS232 I had to open control cabinet. Cabinet has one power source, rated 8 amps at 600Volts. On the top of panel located two step down transformers fed from controller. Panel inside has plastic guard for disconnect, plastic guards for fuse holders, for 600V motor starter and everywhere where is more than 24VDC. On the front of panel is “Power ON” indicator with associated 2 more power indicators plus 34 LED’s process indicators. Inside panel is installed PLC rack with another “Power ON” indicator with 80 I/O rack with 30 or more I/O indicators what is led ON. With wearing leather gloves I disconnected power. At that point all indicators went “OFF” (stop illuminate was indicates there is no power), also indicators “Power ON” went off. By pressing “Power ON “and “Power OFF” push button/indicator I confirmed that panel has no power. Also I pressed “lamp test” Push Button to make sure that is no power. After that still with gloves on I did open panel, plug in cable RS232, cable pass through the door and I closed door.
I understand that since I wear leather gloves, safety glasses and work boots there is no safety violation. from Arc Flush Safety point of view. This is enough PPE to do the job. After opening totally insulated by plastic guards all places with more than 24 Volts and no measure voltage, just plug in PC RS232 cable still is no Arc Flush Safety violation (because no measure voltage or any another activity than plug in RS232 cable). We may talk about electrical shock, but this panel has plastic guards what they secure from accidental touch. Again is no safety violation.
Panel control have had no any Arc Flash lable or PPE lables.
Do I am right?

Thanks for all responders.


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PostPosted: Mon Sep 26, 2011 5:45 am 
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Joined: Wed Jun 04, 2008 9:17 am
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Location: Spartanburg, South Carolina
Had an arc hazard incident energy analysis been done for the MCC? If so, what was the IE?

If no analysis was done, and Table 130.7(C)(9) was used, it would seem from your description, that it would fall under 600 V MCC, Work on control circuits with energized electrical conductors and circuit parts 120 V or below - HRC 0. You would need long sleeve non-melting shirt and pants, safety glasses or goggles, hearing protection, and leather gloves (if exposed parts were < 50 V).


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PostPosted: Mon Sep 26, 2011 6:41 am 
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Joined: Tue Feb 24, 2009 7:05 am
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I don't see "MCC" in Promag's description... looks to me like he was working in an autonomous machine panel with a PLC and also motor starters in the same panel.

Not every motor is started from a MCC...


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PostPosted: Tue Sep 27, 2011 2:07 am 

Joined: Sat May 01, 2010 2:20 am
Posts: 36
Your company should have installed a cat 5 plug with a 120 v outlet on front of panel door for plc troubleshooting. Not an anwser but something you might want to know.


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PostPosted: Tue Sep 27, 2011 5:30 am 
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Location: Spartanburg, South Carolina
Vincent B. wrote:
I don't see "MCC" in Promag's description... looks to me like he was working in an autonomous machine panel with a PLC and also motor starters in the same panel.

Not every motor is started from a MCC...

What section of Table 130.7(C)(9) would you use for an autonomous machine panel? The "Other 600 V Class" section does not have a task for woking on control circuits.


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PostPosted: Tue Sep 27, 2011 8:42 am 
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Location: Connecticut
5 day suspension seems harsh for a questionable safety violation. In my company there is progressive displinary steps. Starting with verbal warning, written warning, moving up to 3 days then 5 day suspension with review for possible termination. Each step is carefully reviewed by HR first. Sounds like there maybe more to this story than Promag is telling.


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PostPosted: Tue Sep 27, 2011 9:11 am 

Joined: Sun Sep 25, 2011 10:00 pm
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First time safety violation...trust me. You right other elements apply not job related.


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PostPosted: Tue Sep 27, 2011 9:18 am 

Joined: Sun Sep 25, 2011 10:00 pm
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jghrist do you mean if exposed parts were more than 50 V ?
This is not MCC. Panel control have had no any Arc Flash lable or PPE lable.
geh 7752 it was first safety violation, have more story not job related


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PostPosted: Tue Sep 27, 2011 10:08 am 
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Location: Spartanburg, South Carolina
Promag wrote:
jghrist do you mean if exposed parts were more than 50 V ? Thanks again for response,

No, I meant that if the exposed parts were > 50 V, leather gloves would not be sufficient.


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PostPosted: Tue Sep 27, 2011 4:46 pm 

Joined: Tue Oct 19, 2010 4:01 pm
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Why could you not kill the power before opening the cabinet? What type of disconnect is it? What is your company policy about this work? Have you had problems with this person in the past? As some one who learned his control work by building this type of cabinets, the plastic is just a "bump" guard. There is no protection from a flash. It sounds as if you thought about what you where going to do and then did it, that's good. I work with a few people who just act without thinking about what can happen first. I have worked with some supervisors who would have done the same to me and others who would stop and explain and show me a different, maybe better, way. I agree with the other post that there should be a port and outlet in the door for this work, we did it all the time for clients when there was high voltage in the cabinet(480-5K)


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PostPosted: Tue Sep 27, 2011 8:01 pm 

Joined: Sun Sep 25, 2011 10:00 pm
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elecfx Look above "With wearing leather gloves I disconnected power".After that "I understand that since I wear leather gloves, safety glasses and work boots there is no safety violation from Arc Flush Safety point of view. This is enough PPE to do the job. After opening totally insulated by plastic guards all places with more than 24 Volts and no measure voltage, just plug in PC RS232 cable still is no Arc Flush Safety violation (because no measure voltage or any another activity than plug in RS232 cable). We may talk about electrical shock, but this panel has plastic guards what they secure from accidental touch."
So plastic "bump" is only for protection against accidental touch (electrical shock).


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PostPosted: Tue Sep 27, 2011 8:06 pm 

Joined: Sun Sep 25, 2011 10:00 pm
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elecfxLook above"With wearing leather gloves I disconnected power".After that "I understand that since I wear leather gloves, safety glasses and work boots there is no safety violation. from Arc Flush Safety point of view. This is enough PPE to do the job. After opening totally insulated by plastic guards all places with more than 24 Volts and no measure voltage, just plug in PC RS232 cable still is no Arc Flush Safety violation (because no measure voltage or any another activity than plug in RS232 cable). We may talk about electrical shock, but this panel has plastic guards what they secure from accidental touch. So plastic "bump" is only for protection against accidental touch (electrical shock).


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PostPosted: Wed Sep 28, 2011 3:32 am 
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Plastic shields and guards in panels aren't fool proof and should never be considered 100% shock prevention protection. Most I've seen are just piece of plastic on the front of a device with the sides open. There is only one proven method to prevent accidental shock or an arc flash event... disconnect the power.


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PostPosted: Wed Sep 28, 2011 2:53 pm 

Joined: Tue Oct 19, 2010 4:01 pm
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I guess than what your saying is that you are able to open the disconnect without opening the cabinet, I thought you ment you had to open the cabinet to operate the disconnect. If you are able to operate the disconnect from outside of the cabinet than it sounds like you are correct, based only on what you have told us. I guess that your company is following 70E and has not done a study or has some other rules in place. If so your anwser is in tables in 130. Sounds like you have a Richard Cranium at your work based on the info you have given.

By the way, how did you test for lack of voltage? Hope you are not trusting lights? I have first hand knowledge of a bad disconnect that didn't open fully.


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PostPosted: Tue Oct 11, 2011 4:24 am 
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Joined: Fri May 01, 2009 9:10 am
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Company Safety Program

Violation of a company's safety program and NFPA 70E/ OSHA compliance can be 2 separate issues. The disciplinary process (suspension) can be punitive or corrective or both. In order for it to be corrective, a detailed letter should outline what you did as compared to what you should have done; thus the violation. Without Arc Flash labels, I'm curious about the imposed arc flash safety program and how it is enforced.


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