Connecting large EGC in the box

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Alexei

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Location
Massachusetts
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Engineer
I am in Mass; NEC 2020

I have a metal box with ground wires
- 3 x 10 AWG
- 2 x 14 AWG
I understand I need to connect all 5 cables together, and to the box

Usually I connect ground wire using Greenie Grounding Wire Connectors 92 and leave one cable longer to go through connector hole and connect to the box.

I can not find any connection which is rated for the wire combination I have.

I am contemplating a crimp connector, e.g.
http://www.nsiindustries.com/catalog/nsiproducts/connectors/easy-twist/sb1808
https://www.gardnerbender.com/en/products/Connections/Crimp-On-Connectors
but I do not know if it is listed for such application, or if it even would fit.

Another options is to install a ground bus, but can not find anything listed either.

Could you please advice a NEC compliant option to do it.
 
These are good for 6-#10's. You could also make two splices and put a jumper in between just make sure that you do not exceed the number and wire size of the wirenuts. So you can put 2-#10+2-#14 in one splice and 4-#10 in another. That gives you the original 5 conductors plus a #10 jumper to the box and a #10 jumper between the two splices.
818ZgohcWCL._SL1500_.jpg
 
Jon456 said:
Is the metal box a junction box or something else? What size is it?
Click to expand...

I was thinking, I'd use metal 4-11/16 in. square box, 3-1/4 in. deep. I can use another box too, if it somehow helpful here.

The box will be used to splice - changing wiring method from NM to THHN-2:
- 2x NM 10/2 <=> 4x THHN-2 10 AWG
- 1x NM 14/2 <=> 2x THHN-2 10 AWG
and for the ground
- 2x 10 AWG (from 2x NM 10/2)
- 1x 10 AWG (from THHN-2)
- 1x 14 AWG (from 1x NM14/2)

Total ground wires
3x 10 AWG + 1x 14 AWG if I can use a connector method which allows one wire to be longer and connect to the metal box, or
4x 10 AWG + 1x 14 AWG if I have to use a pigtail to connect to the box
 
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infinity said:
These are good for 6-#10's. You could also make two splices and put a jumper in between just make sure that you do not exceed the number and wire size of the wirenuts. So you can put 2-#10+2-#14 in one splice and 4-#10 in another. That gives you the original 5 conductors plus a #10 jumper to the box and a #10 jumper between the two splices.
Click to expand...

Thank you very much @infinity

Can I still use these for ground wire under NEC 2020? I thought I could not. From 3M website:
- SG-G are UL listed as "Grounding Connector"
- All other connectors are UL listed as "Pressure Wire Connector tested"

So, under NEC 2020, do I need to connect with something which is UL listed as "Grounding Connector", or can I use any connector which is listed for wires size combination.

If I do not need to worry about "Grounding Connector" - it solves my issue.

I do understand part of the answer that I can do it as two bundles cross-connected with pigtail, but then I still need each to be 3x 10 AWG or better.
 
Any wire connector can be used for EGCs. There are some like the Greenie that can only be used with the EGC.
 
infinity said:
Any wire connector can be used for EGCs. There are some like the Greenie that can only be used with the EGC.
Click to expand...

Thank you so very much, Rob.

I was confused in thinking that the connector needs to be specifically listed for EGSs these days, and I can no longer use other wire connectors. Makes perfect sense now.
 
Alexei it appears this is a DIY project and we are not really allowed to help you with the install. I know you are an engineer as are many of our moderators. They also cannot ask diy questions. Hope you understand but I need to close this thread
 
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