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Planning for future - compressor outlet

sberry

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The box is bonded thru the recept. I am all for reading up if you can point me in the direction that says we got to bond this box other than the recept. I understand that if we were using the box and a pipe as a grounding conductor and the device was mounted in the cover we need a bond wire. In this case the ground is mounted to the yoke of a self grounding recept. I think if it needed it there would be another green screw on it.
 
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katit

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I'm aware that boxes have to be grounded even though outlet also have ground. Advice for screw-on lug is a good one. I do agree 10 wire will do fine on a green bolt but #6/#8 is too much and I see it.

Thanks for all advice here, it's really helpful.
 

JBurgess

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The box is bonded thru the recept. I am all for reading up if you can point me in the direction that says we got to bond this box other than the recept.

250.148(B)

(B) Grounding Continuity. The arrangement of grounding
connections shall be such that the disconnection or the
removal of a receptacle, luminaire, or other device fed from
the box does not interfere with or interrupt the grounding
continuity
.
 

sberry

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Here is the situation they are trying to avoid, the recept is mounted to the cover with this one little screw, where the pipe is a ground they want a jumper to the box, don't want a fault carried by this little screw that has a tendency to work loose and is very small.
The second cover is way better but I still run the jumper, does anyone know if this cover meets the listing? I think if the ground wire runs to the device it does as it doesn't disconnect the recept in case of removal but thats a guess. I am not sure the connection to the ground pin in a 6-50-R is listed for use with multiple wires
 

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JBurgess

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Lets look back a bit to 250.146 By the way, I got no problem with being enlightened here.

250.146 Connecting Receptacle Grounding Terminal to
Box. An equipment bonding jumper shall be used to connect
the grounding terminal of a grounding-type receptacle
to a grounded box unless grounded as in 250.146(A)
through (D). The equipment bonding jumper shall be sized
in accordance with Table 250.122 based on the rating of the
overcurrent device protecting the circuit conductors.

This is for grounding a receptacle to a "grounded box" by means other than a jumper.

If you did want to omit the bonding jumper with the box grounded, you would have to apply (A) through (D)

(A) does not apply since it is not surface mounted.
(B) does not apply unless you can find a 6-50-r that is listed as self grounding
(C) does apply since it is not a floor box
(D) does apply since it is not an isolated ground.
 

JBurgess

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A 6-50-R is listed as a grounding type recept. It is a 2 pole 3 wire grounding recept.

Self grounding have the little metal clip on one of the screws to bond the screw and the recepticale.

gray2_004.jpg
 

JBurgess

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http://www.frentzandsons.com/Hardware References/plugandreceptacleconfiguratio.htm It isnt my opinion that the outlet in question is a grounding type.

It is a grounding type, just not a self-grounding type. It has to listed as self-grounding.

(B) Contact Devices or Yokes. Contact devices or yokes
designed and listed as self-grounding shall be permitted
in conjunction with the supporting screws to establish
the grounding circuit between the device yoke and flushtype
boxes.
 

JBurgess

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Why let a good thread die?

Here's a #10 solid on a grounding screw

PICT0909.jpg


PICT0910.jpg


the #10 looped around the screw with a twist so it won't pull out.

PICT0911.jpg


A lug is a good way to go if you are using SER:

PICT0904.jpg
 

MrMark

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I like the twist idea.

It's just easier to use the .39 lug kit though.

You obviously have that screw and wire as perfect as it could be. I doubt most would come anywhere close to that. Now, go tighten that down with a hex drive and see what happens. Not the poor slotted tip that can't apply any torque. Use a real hex driver and properly torque that screw and see what happens. Try it when the wire is not perfectly preformed around that screw.

I may incorporate that twist idea on other boxes. I usually just leave one ground long and wrap it around the screw and then use a green nut or crimp and take that long one on to the plug. Only works with singles. Double devices you need to get creative. Maybe you have a nice way to do double and triple devices ground pigtails?
 

MrMark

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OK, Jburgess, the twist method has issues. It creates an increase in diameter at the twist that prevents the screw and looped wire from making full contact. In other words, the screw cannot sit flush. It is just like the no no of crossing the wire under the screw.

I like those pliers. What is the brand and model number?
 

JBurgess

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OK, Jburgess, the twist method has issues. It creates an increase in diameter at the twist that prevents the screw and looped wire from making full contact. In other words, the screw cannot sit flush. It is just like the no no of crossing the wire under the screw.

I like those pliers. What is the brand and model number?

I supose there is a bit of art to getting the twist in the right place. 50 years of practice helps. You should see my western union splices.:)

Here's a good selection of pliers:

http://www.shorinternational.com/pliersroundnose.htm

I can get the exact info off mine next week when I'm at that shop.
 

sberry

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Something I want to add. When i start out way back when I use a lot of dryer and range cord plugs for everything, its not the best idea and lots of stuff got put together at the spur of the moment and that stuff was plentiful. That stuff is still used in that fashion by the DIY crowd but an important thing to remember especially with that stuff is that the yoke IS isolated from the N pin. In my shop and buildings the wiring is piped so the boxes are grounded, where its on a cord or cable though it isn't, neither is the backing plate on surface mount recepts.
I realize this is not the ideal setup but they do get used this way and need a bonding jumper if they are fed with cable or cords.
 
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katit

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Something funny here. We discuss box for welder outlet, grounding posts, etc.

EVERYTHING because I decided on 6/2 for welder outlet and NOBODY stopped and reason me against it.

So, I'm researching welder. Seems like hobart 187 is all I will need (already overkill for my use! ) and It needs 20.7A on 240V. Which makes 10/2 wire just fine for application and I had hard time finding more demanding spec for welder. 8/2 probably all that's really needed.

It's too late now, I have 6/2 wire and will go with it, but... I just want to see inspector's face when I tell him it's for welder :)
 

sberry

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It seems several posts and threads were regarding wire size for that class of machine, didn't you have 8 and return it for 6? But, 10 is ideal for a 187, 12 is sufficient. I like a minimum of 10 though as it could be used for some other machines if needed. Most ready made cords called welder cords come number 8.
 
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mrb

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Something I want to add. When i start out way back when I use a lot of dryer and range cord plugs for everything, its not the best idea and lots of stuff got put together at the spur of the moment and that stuff was plentiful. That stuff is still used in that fashion by the DIY crowd but an important thing to remember especially with that stuff is that the yoke IS isolated from the N pin. In my shop and buildings the wiring is piped so the boxes are grounded, where its on a cord or cable though it isn't, neither is the backing plate on surface mount recepts.
I realize this is not the ideal setup but they do get used this way and need a bonding jumper if they are fed with cable or cords.

could you elaborate a bit on what you are talking about here? Yoke isolated from N pin?
 

JBurgess

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It's here: http://www.garagejournal.com/forum/showthread.php?t=53538
Starting at post #8. Nobody even blinked their eye on 6/2

Ok. What kind of welder needs 6/2? I'm cuirous now..
I also need to know how my 6/2 outlet can be useful in garage :)

It's here: http://www.garagejournal.com/forum/showthread.php?t=53538
Ok. What kind of welder needs 6/2? I'm curious now..
I also need to know how my 6/2 outlet can be useful in garage :)

This kind of welder- 60A @ 60% duty cycle requires conductors good for 46.8 amps. Overkill for a home shop, but sometimes can be found cheap.

PICT0967.jpg


PICT0765.jpg


As for other uses, I have friends that use 50 amp circuits for powder coat ovens and pottery kilns.
 

sberry

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could you elaborate a bit on what you are talking about here? Yoke isolated from N pin?
Old 3 wire dryers and ranges have insulated Neutral, there is no connection between it and the mounting hardware that holds it in the box. There is no bond between it and the backing plate on surface recepts, if using one on a cord the metal back in ungrounded. With grounding type outlets such as welder recepts there is a rivet that makes this bond.
There might be other uses for a 6-2 besides a welder, a pottery kiln or some kind of oven that needs full 50A service.
 

mrb

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Old 3 wire dryers and ranges have insulated Neutral, there is no connection between it and the mounting hardware that holds it in the box. There is no bond between it and the backing plate on surface recepts, if using one on a cord the metal back in ungrounded. With grounding type outlets such as welder recepts there is a rivet that makes this bond.
There might be other uses for a 6-2 besides a welder, a pottery kiln or some kind of oven that needs full 50A service.

ah ok. Shouldnt be using those old 3 wire dryer and range receptacles....should be 6-30 and 6-50 (or 14-** if you need a neutral)
 

sberry

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Yes, they are commonly used portable, I guess they figure so many get cobbled to dryer outlets they might as well come up with a way to do it. When you first mention it I thought maybe a 14 was available too for engine drives.
 
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katit

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I had problems with a switch being left on when not needed, so installed a P & S TMHWL-ECC night light next to it. Might help to keep from forgetting to turn the compressor off. The one with the light sensor was cheaper, so I just colored over the sensor with a black sharpie. It's 110 volt so you will need a neutral up to the switch.

PICT0831.jpg


PICT0833.jpg


I wonder what behind the plate? :) What size wire?

I got 4 11/16 deep metal box at Grainger with mud ring. I beleive it will be big enough to host 8/2 and 8/3 wires.

Now I wonder where to get this night light. Do you have online link? If they have 40A rocker switch so I can get them together - would be great.

I also assume I will need to downsize wire for light itself using twist connector?

Is this stuff OK by codes/etc?



In description it says:
Terminal screws accept up to #10 AWG solid copper wire. For stranded #8 AWG wire, remove terminal clamp and use ring terminal

Do I just crimp ring terminals on?
 
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JBurgess

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I wonder what behind the plate? :) What size wire?

I got 4 11/16 deep metal box at Grainger with mud ring. I beleive it will be big enough to host 8/2 and 8/3 wires.

Now I wonder where to get this night light. Do you have online link? If they have 40A rocker switch so I can get them together - would be great.

I also assume I will need to downsize wire for light itself using twist connector?

Is this stuff OK by codes/etc?




In description it says:
Terminal screws accept up to #10 AWG solid copper wire. For stranded #8 AWG wire, remove terminal clamp and use ring terminal

Do I just crimp ring terminals on?

This switch will accept #8 :

http://www.electricsupplyonline.com/...0c_w011444.php

I got the night light at Lowes for around $10.
 
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katit

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Can you repost switch link? It's broken.
Thanks! I will check lowes tonight.

What gauge wire did you use?
 

MrMark

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8 gauge is perfect. 10 is a little too small and 6 is a little bit overkill. I went 6 on one outlet (because I had it) and 8 on the other.
 
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katit

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Ok. You got me convinced. I only regret not getting 8/3 for everything. I got piece of 8/2 and piece of 8/3.

Switch ordered. Hopefully I will be able to get it all in.

Oh, and since I'm here another Q. Metal box I got from Grainger is 4 11/16 with mud plate. There is no holes on a side to mount to stud? There is 2 holes but they are very close to top if you know what I mean. Should I drill new holes to attach this box to stud?
 
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