Jpflex
Electrician big leagues
- Location
- Victorville
- Occupation
- Electrician commercial and residential
Yes that’s a valid point, i only said mc cable because that is what it looks like. I’m not sure if it could be FMC, AC or even MI but I’ll touch the cover next time I’m there to verify if it’s plastic or metal.How do you know it was even MC? If it is MC (and of course AC) the armor needs to be grounded and that plastic plate doesn't do it. If a stainless steel plate was used it would be OK in that respect.
-Hal
It’s definitely not MI.“. . .could be FMC, AC or even MI. . .”
Wouldn’t drilling holes into a faceplate have to be authorized or approved for in field installations for modifications to listed supplies?
I was told by my former boss that holes that are made in boxes in field installations must be approved. Same for drilling screws to hold in plastic nm single gang boxes instead of using supplied nails on tabsIf making holes were not allowed we should all get rid of our hole cutters and KO punches.
And I guess never use enclosures that have no KO's.
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Approved by whom? Plastic boxes with screws on the inside have their own requirements. Metal boxes can be field drilled for mounting.I was told by my former boss that holes that are made in boxes in field installations must be approved. Same for drilling screws to hold in plastic nm single gang boxes instead of using supplied nails on tabs
He probably meant approved by HIM. I agree holes need to be approved by the guy responsible for getting them in the right place. In my case that's me as a person who works without a helper most time.I was told by my former boss that holes that are made in boxes in field installations must be approved.
Using a metal cover would only bond it if the box was metal also. The possibility exists that this is a plastic box and NM as a wiring method. I agree a metal plate would be the best practice to use, to avoid the inevitable broken plate.How do you know it was even MC? If it is MC (and of course AC) the armor needs to be grounded and that plastic plate doesn't do it. If a stainless steel plate was used it would be OK in that respect.
-Hal
I always used a metal plate then drilled a hole to install a ground screw with a nylock nut to bond the cover. I never trusted two flimsy 6 /32 cover screws to provide a dependable ground especially if the metal box or mud ring wasn't flush with the wall, location that could get damp and while running #10 copper or heavier wire. In my area luckily for guess last 40 years you are not allowed to run AC cable in any Industrial sites. Nothing beats a copper ground wire. For feeding office furniture I always used stainless steel blank covers verses plain Jane white painted steel plates.I saw this at a local enterprise car dealer lobby but is it NEC code compliant to cut a hole in a plastic blank face plate and insert mc cable with 90
Degree connector ?
My reason for using the plastic plate is, that's what I had on the van!My reasoning for a metal plate is strength first and grounding second.