Grounding a junction box

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tommyh

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Question: Is it true that if you run EMT conduit and install a junction box and continue the conduit run...... that if you do not make any splices in that junction box and the wires pass right through to the next conduit......you do not have to "ground" that junction box because there are no splices nor devices installed??
 
Most likely your conduit would be your ground and if you had no splices or connections to devices in the box no additional ground would be required but the box is grounded.
 
I looked in the UL White Book and then read the NEC Handbook commentary - they seem to conflict??

UL says EMT fittings are suitable for grounding [thus maintaining the continuity through the box].

If that is the case, then even if you did splice the conductors the 'suitable for grounding' EMT fittings should satisfy the requirements of 250.148(C).

OR - is 'suitable for grounding' not the same as 'equipment listed for grounding' and you do need additional bonding should you splice? [This seems to be what the Handbook is saying].
 
The difference is that if you run an EGC in the conduit with the conductors and you make a splice in the JB then you would have to ground the box. If no splices are present then there is no need to ground the box. This is as Gus stated with the reference to 250.148
 
Dennis Alwon said:
The difference is that if you run an EGC in the conduit with the conductors and you make a splice in the JB then you would have to ground the box. If no splices are present then there is no need to ground the box. This is as Gus stated with the reference to 250.148
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So if you use EMT as your EGC and make a splice in the box, you don't have to establish an additional bond? [because the EMT has already done this].

But - if you run a wire EGC conductor with your conductors in EMT, then you do have to bond the wire EGC to the box [even though this is a redundant EGC]??
 
dana1028 said:
So if you use EMT as your EGC and make a splice in the box, you don't have to establish an additional bond? [because the EMT has already done this].

But - if you run a wire EGC conductor with your conductors in EMT, then you do have to bond the wire EGC to the box [even though this is a redundant EGC]??
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In my opinion, all bonding is redundant. That's the whole point of bonding.
 
dana1028 said:
So if you use EMT as your EGC and make a splice in the box, you don't have to establish an additional bond? [because the EMT has already done this].

But - if you run a wire EGC conductor with your conductors in EMT, then you do have to bond the wire EGC to the box [even though this is a redundant EGC]??
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Yep, that's what it says. :)
 
tommyh said:
Question: Is it true that if you run EMT conduit and install a junction box and continue the conduit run...... that if you do not make any splices in that junction box and the wires pass right through to the next conduit......you do not have to "ground" that junction box because there are no splices nor devices installed??
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its a pull box
 
RETRAINDAILY said:
He is talking about a pull box
look in the index of the NEC look up pull box it don't say anything about 250.148
250.148 is talking about boxes and junction boxes
you have to bond them.
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If you are saying that pull boxes are not covered by 250.148, I don't agree. All boxes, no matter what you call them, are covered by the section.
 
Well a box is a box pull box or junction box .

If we use a pull box with say large feeders the largest ground in any of the raceways will be that ground bonded to that box in that pull box or junction box with a pass thur mechanical lug to case .
 
RETRAINDAILY said:
It is a box
junction boxes do not refer to 250.148 they both refer you to boxes
and what he has is still a pull box they are two different things.
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They are one in the same for the application of 250.148. If you think different, please provide the code citations to support your point.
 
As for the OP, I believe what he has been told is generally true. 250.148 specifically states that splices or terminations to devices are present to apply. In this case 250.148 does not apply.

Would bonding the EGC to the box make the installation safer ? Absolutely.

One special case at least exists that does call for the EGC to be bonded, 517.13B.
 
jwjrw said:
Most likely your conduit would be your ground and if you had no splices or connections to devices in the box no additional ground would be required but the box is grounded.
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but what if the box is mounted on a pvc coated mounting rack? this is outdoors BTW. since the rack is integrated to the electrical system, as a non-current carrying item, will it require some sort of bonding or grounding?

Thanks for all your info.
 
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