New safety questions

[safetybobnj]

I am getting hit with some questions I cannot answer or find in OSHA Subpart S or the NEC. I work in tactical safety and have little electrical background.

1. On a 20 amp branch circuit having several duplex receptacles each of the receptacles MUST be rated at 20 amps?

2. There is a broken ground pin is on an extension cord protected by a GFCI. Will the the external GFCI tester trip the GFCI?

Thx in advance.

Safety Bob

 

[charlie b]

Re: New safety questions

Hit by whom? Where are these questions coming from? We are not here to answer anyone?s homework for them, or to take the place of a person?s own research.

How about telling us what you think the answers are, and why? How about telling us where you looked in the code? If you don?t make an attempt on your own, then I don?t think you will get much assistance here.

 

[safetybobnj]

Re: New safety questions

I am a federal employee and am getting questions from a listserver we have in place. Some come from the active Army, some from the National Guard, some are coming from people (either civilian safety professionals or soldiers serving in the safety officer capacity) serving over in Iraq and Afghanistan; I too mobilized and served in Kuwait and Afghanistan myself for a year and used our listserver quite extensively to get confined space, electrical, HAZMAT questions, etc., answered. I do NOT have an electrical background, just an OSHA course. I guess our "homework" is quite different from yours. I post questions posed by colleagues hoping for an answer. I will not post my "homework" questions from the War College I have on this forum as that would be inappropriate right??

Having said all that:

I conducted hits on the OSHA webpage and went thru all the pages in the NEC as I have a copy of NEC 2000 for my research.

My best semi-educated (I only hold a MS degree) guess would be that:

1. They must be rated higher due to the 125% rule.

2. GFCIs detect flow differential in black and white wires. It will trip if you press the test switch on the external tester.

Sorry for my ignore of electricity and being able to delve deeper into OSHA and the NEC.

 

[pierre]

Re: New safety questions

For a multioutlet branch circuit, the 20 amp circuit can have 15 amp rated receptacles installed.

The GFCI senses between the grounded conductor (white as you said) and the ungrounded conductor (black conductor as you said). The ground pin is not necessary for the GFCI, but is necessary for OSHA.

Charlie meant no harm, he is protecting the way we conduct ourselves on this site.

 

[don_resqcapt19]

Re: New safety questions

If you are trying to use a plug in GFCI tester on the end of a cord that has a missing ground pin on the plug, then the plug in tester will not work. That tester works by placing a ~8mA load between the hot and the grounding conductor. If the grounding pin is missing at the plug there is no complete path for the test current.
Don

 

[roger]

Re: New safety questions

Safetybobnj, why didn't you explain this upfront. Charlie was not out of line at all and you shouldn't be upset.

Roger

 

[charlie b]

Re: New safety questions

Originally posted by safetybobnj: (I only hold a MS degree)

So do I. I started the PhD program, but could not do the thesis research at the same time I was working, so I never finished it. Your guesses were based on common sense, and I think they were good guesses. But Pierre and Don have given the correct answers. Let me add two tidbits:

TIDBIT ONE: NEC 210.21(B)(3) and its associated table state that it?s OK to have 15 amp receptacles on a 20 amp branch circuit, so long as there are two or more receptacles.

TIDBIT TWO: Pierre and Don did not contradict each other, even though it may appear at first glance that they did. Pierre is right, and you were also right, in that the GFCI would operate correctly, even if the Equipment Ground Conductor (green wire, or the round plug) were disconnected. Nevertheless, the commonly used testing device would not operate properly.

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By the way, I also served in the military overseas, but never in a true combat situation. Many members of this forum have. I proudly stand up and salute you, and all the others who have served, and are serving, in our armed services.

 

[bennie]

Re: New safety questions

Safetybob: You indicate you are a federal employee. I assume you are an officer in the military, not a civil service worker.

The mention of war college gives me a hint.
I would like to read the war college questions, but like you say they would not be proper on this forum.

My regards, and good luck.

Bennie