Plug and Cord connected load, supplemental grounding

[cwrsrp]

Per the NEC, if a load is plug and cord connected, is it allowed to have a supplemental ground rod? This point was tabled because the load can easily be unplugged thus removing the requirement of the supplemental rod to be bonded to the equipment grounding conductor system (and posing a potential dangerous situation).
Thanx all in advance!

 

[charlie tuna]

Re: Plug and Cord connected load, supplemental grounding

what good would a "supplemental ground rod" do? we are finding out that ground rods are about useless..............

 

[bphgravity]

Re: Plug and Cord connected load, supplemental grounding

Supplemental grounding of electrical equipment is permitted by the NEC. This doesn't negate the requirement for an equipment grounding (bonding) conductor to be run with the circuit conductors serving the equipment.

I don't understand your concern of a potential danger if the equipment is unplugged? In all reality, the supplemental ground rod serves almost no purpose.

 

[petersonra]

Re: Plug and Cord connected load, supplemental grounding

I think you are suggesting the ground rod is connected to the frame of the device, so that when the cord is unplugged the ground rod is alos unconnected.

If you think about it, this is actually a pretty common situation. many plug and cord connected devices are mounted to frames that are effectively bonded to building steel. No hazard that I can see, but no benefit either.

AS LONG AS THE CORD HAS A BONDING CONDUCTOR IN IT!!!!!

 

[kiloamp7]

Re: Plug and Cord connected load, supplemental grounding

As long as the cord has the proper NEC equipment grounding (bonding) conductor in it - that is the important thing.

Otherwise, you can use supplemental equipment grounding (either bonding or earthing to the equipment itself) to your heart's content. It probably does not accomplish much, but it is NEC recognized.

 

[cwrsrp]

Re: Plug and Cord connected load, supplemental grounding

Guys n Gals, let me rephrase...NEC 2002, 250.54 emphasizes the point of connecting the supplementary grounding electrodes to the equipment grounding conductors. It also states the earth (through the supplementary rod) shall not be used as the sole equipment grounding conductor. Therefore, since plug and cord connected loads are indeed meant to be unplugged, it seems to me this would be a code violation (by interpretation) to connect a supplementary ground rod to a cord and plug connected load because when it becomes unplugged, the earth (through the supplementary ground rod) is indeed the sole equipment grounding conductor (whew)...comments?

 

[crossman]

Re: Plug and Cord connected load, supplemental grounding

2005 NEC Section 250.54 covers it. I think a lawyer could argue the case either way.

I would say the cord and plug is okay. The section says "shall be permitted to be connected to the equipment grounding conductors..."

meaning... it can be, but doesn't have to be. And if the equipment is unplugged, there is no need for a ground fault path. The reason I say this is that unplugging the equipment also breaks the EGC path... now, maybe THAT is a code violation?

 

[izak]

Re: Plug and Cord connected load, supplemental grounding

there is no need for an 'effective fault path'
when there is no FAULT available....

do you bond the fencepost that supports your mailbox?
no!

 

[hurk27]

Re: Plug and Cord connected load, supplemental grounding

Why would you need a ground rod if all power is removed from this equipment when it is un-plugged?

Is it equipment that might be struck by lightning?
Like a radio or TV? If it is just disconnect the antenna from it. I'm not getting what your asking. What type of equipment are you wanting to install this ground rod to?