More than one wire under a screw terminal

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kwired

kwired

Electron manager
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NE Nebraska
Not familiar with the cable in question, but something tells me the three together must be used as one EGC - so that sort of makes it one conductor? Kind of like the concentric bare conductor in SE cable or other similar cables.

They appear to be smaller then the insulated conductors on what looks to be less then 10 AWG, but not really certain what thickness of insulation is either.
 
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jap

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As far as more than one conductor under a screw, it's fine on the EGC's to do that as long as the terminal is actually rated for such.


Jap>
 
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kenaslan

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Location
Billings MT
kwired said:
Not familiar with the cable in question, but something tells me the three together must be used as one EGC - so that sort of makes it one conductor? Kind of like the concentric bare conductor in SE cable or other similar cables.

They appear to be smaller then the insulated conductors on what looks to be less then 10 AWG, but not really certain what thickness of insulation is either.
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Thats a 12/3 Okonite CLX 546-31-3453 with 3 #16 grounds. However if you look closely, you can see what appears to be a single #16 from the ground strip to the TB-480V ground. That wire should be up sized to a #12 and landed under its own termin.
 
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jap

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I don't think the grounding terminal blocks on the denrail are rated for more than one conductor but I may be wrong on that.


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jap

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Different strokes for different folks.

The unused wire not terminated is not a violation.

The wiring in this cabinet is not complete as of yet, so, we're not getting the whole story right now anyway.


JAP>
 
kwired

kwired

Electron manager
Location
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kenaslan said:
Also, no ground from the back plate to the box.
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What do instructions for that enclosure say? I see you used a star washer on lower left mounting stud - that is probably all you needed to do to ensure bonding between the enclosure and the back panel. You probably did need to remove paint behind that grounding bar though or install a bonding jumper to ensure good bonding to that bar.
 
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jap

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kwired said:
You probably did need to remove paint behind that grounding bar though or install a bonding jumper to ensure good bonding to that bar.
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Nah....no use to ruin a perfectly good looking factory paint job.

Besides, it looks like the time was taken to drill the holes and mount the bar with (2) tapping screws that I'm pretty sure catch 2 threads.

If anything,
Install the Ground Bar vertical or move it over so it doesn't encroach on the denrail.
Cut the denrail and the wire management square so it looks presentable.
Move the wiring duct over a little bit so you can get a socket on the backplate nuts.
Group the ground terminal blocks together on the terminal strip and jumper them together with a jumper to a lug attached to the backplate mounting stud with a lug. Not required but.....
Don't take uninsulated grounding conductors up to the terminal blocks, let them drop off on the ground bar on the backplate down low.
No need having uninsulated EGC's floating around close to the 480 on the terminal strip.
Either land that blue and mark it as a spare or at least put a wirenut on it.

Ooops,,, sorry,,, for a minute I had a flashback of me talking to my apprentice. :)


JAP>
 
kwired

kwired

Electron manager
Location
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I don't know that those yellow blocks are grounding blocks, I think they are just yellow blocks.

True grounding blocks won't need jumpers between them, they will have a means to bond to the DIN rail.
 
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jap

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kwired said:
I don't know that those yellow blocks are grounding blocks, I think they are just yellow blocks.

True grounding blocks won't need jumpers between them, they will have a means to bond to the DIN rail.
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That's true.
I just don't like depending on that type of connection but that's just me.

JAP>
 
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jap

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Simply because the denrail probably makes less contact with the grounded surface more so than the ground bar in the picture because of all the paint behind it.


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kenaslan

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Location
Billings MT
This IS what came from the factory. Besides, Oil drilling facilities are BEYOND cheep. Considering a drill site has a life of less than 30 years, they don't care. But who knows, Technology keeps improving. Rod Pumps, Gas Lift, Submersible pump, Fracking
 
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jap

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kenaslan said:
This IS what came from the factory. Besides, Oil drilling facilities are BEYOND cheep. Considering a drill site has a life of less than 30 years, they don't care. But who knows, Technology keeps improving. Rod Pumps, Gas Lift, Submersible pump, Fracking
Click to expand...

What are those leads going to?


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