[47_47]

Plan on running a 15 amp (14g) and a 20 amp (12g) circuit to a metal box using romex.

Do both of the ground wires need to bond the metal box, or can I just bond the 12g?

 

[electures]

No. Just the larger of the two.

 

[JulieMor]

You are going to splice the grounds together and pigtail a ground to bond the box, right?

 

[47_47]

No, I was planning on looping just the 12g around the bond screw, leaving it long and wire-nutting the 14g ground and device grounds to that.

 

[electures]

You are going to splice the grounds together and pigtail a ground to bond the box, right?

Wouldn't that be paralleling them?

 

[stickboy1375]

All the grounds need to be spiced together and the box bonded.

 

[stickboy1375]

Wouldn't that be paralleling them?

And thats not an issue...

 

[electures]

And thats not an issue...

Where in the NEC does it require all the grounds be spliced together?

 

[frenchelectrican]

Wouldn't that be paralleling them?

No not on the ground due it is not a current carry conductor at all.

All the grounds need to be spiced together and the box bonded.

And thats not an issue...

That I been doing on both side of USA and France for many years and never have a issue with that at all.

Where in the NEC does it require all the grounds be spliced together?

I havent check the NEC for a little while but I can able dig it up when I get to my office and find out with it. Our French codes do requried that it have to be spliced together by either wirenut or wago or block connector or screw on the metal box one of metholds are approved for this purpose.

Merci,
Marc

 

[stickboy1375]

Where in the NEC does it require all the grounds be spliced together?

Let me dig it up, but it does exist.

Im going with 250.148 (C)

 

[JulieMor]

Where in the NEC does it require all the grounds be spliced together?

If you don't have a ground whose path isn't continuous back to the primary ground, you will have an ungrounded load. I don't need the NEC to tell me that is dangerous.

 

[jlmran]

If you don't have a ground whose path isn't continuous back to the primary ground, you will have an ungrounded load. I don't need the NEC to tell me that is dangerous.

His question was about bonding the grounds of two separate circuits, in a common box.

 

[jlmran]

So, to me, the obvious next question is, "why?" Let's assume there is a junction box with conductors from two separate circuits. Lets assume one circuit is 20 amp and one is 15 amp. Lets also assume that only the EGC from the 20 amp circuit is bonded to the box, and that the two EGCs of both circuits are NOT bonded at this box. What is the danger which serves as a basis for the code requirement?

 

[stickboy1375]

So, to me, the obvious next question is, "why?" Let's assume there is a junction box with conductors from two separate circuits. Lets assume one circuit is 20 amp and one is 15 amp. Lets also assume that only the EGC from the 20 amp circuit is bonded to the box, and that the two EGCs of both circuits are NOT bonded at this box. What is the danger which serves as a basis for the code requirement?

It's just redundancy, to ensure proper ground fault protection.

 

[Speedy Petey]

I'm going with all of 250.148.
If the circuits are spliced, ALL equipment grounds must also be spliced.

250.148 Continuity and Attachment of Equipment Grounding Conductors to Boxes.

Where circuit conductors are spliced within a box, or terminated on equipment within or supported by a box, any equipment grounding conductor(s) associated with those circuit conductors shall be connected within the box or to the box with devices suitable for the use in accordance with 250.148(A) through (E).

Exception: The equipment grounding conductor permitted in 250.146(D) shall not be required to be connected to the other equipment grounding conductors or to the box.

(A) Connections. Connections and splices shall be made in accordance with 110.14(B) except that insulation shall not be required.

(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.

(C) Metal Boxes. A connection shall be made between the one or more equipment grounding conductors and a metal box by means of a grounding screw that shall be used for no other purpose, equipment listed for grounding, or a listed grounding device.

(D) Nonmetallic Boxes. One or more equipment grounding conductors brought into a nonmetallic outlet box shall be arranged such that a connection can be made to any fitting or device in that box requiring grounding.

(E) Solder. Connections depending solely on solder shall not be used.