200 AMP 300V MURRAY double RING meter box With NO Grounding Lug

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alyoshak24

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Chicago
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Electrician
BACKGROUND - Installing Grounding Electrode System for a 2 story 2 tenant house in Chicago each floor having a corresponding meter. After Driving 2 ground rods 8 ft apart from each other and running my green #8 to the meter enclosure, i attempted to terminate into the grounding lug (which is usually below or adjacent to the grounded lug of meter box and usually smaller than the grounded lug) but this meter enclosure, which is older ring style, does not have that adjacent grounding lug. This is getting expected next week and need to reconcile this issue; my question to the Masters/Experts nationwide is:

  • Can i terminate the GEC to the load side neutral lug of either meter can ? if not then ~

  • Can I terminate the GEC to the grounding bushing on either of the 1/2 or 3/4 EMT grounding bushings and leave it at that since the Neutral lug is bonded to the meter enclosure? if not then ~

  • Since it is mounted on brick, drilling and tapping is out of the question, is there a GEC lug kit for this MURRAY model double ring meter can (Retrofit code compliant GEC Kits) ? if there arent then ~

  • what do i do in this situation of 1 - 3 are not an option or against code ?
** Upgrading/changing out double ring Murray meter box to a new double ringless or ring meter box is not an option **

**** Can you please provide NEC excerpts/sources sited or supplemental YouTube vids or pics of your guys work how you got a similar situation to work out. ****

THANK YOU MAESTRO'S
 

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If I'm not mistaken, I used that meter a few years ago and found out after I had it installed that the ground lug doesn't come with it, it is a separate piece that has to be bought and installed.
 
Why a 8 AWG GEC? That size must be protected in a raceway.
Have you checked your poco standards on grounding? They are very particular about the cash register.
 
We sometimes post pictures, we are all to busy to fuss with you tube, and many like my self don’t care for YouTube.
 
tom baker said:
Why a 8 AWG GEC? That size must be protected in a raceway.
Have you checked your poco standards on grounding? They are very particular about the cash register.
Click to expand...
Everything in Chicago and neighboring counties of illinois is protected in a raceway. and it is in 1/2 EMT
 
Little Bill said:
If I'm not mistaken, I used that meter a few years ago and found out after I had it installed that the ground lug doesn't come with it, it is a separate piece that has to be bought and installed.
Click to expand...
Do you know where i can purchase this piece because i am not having any luck on the interwebs
 
alyoshak24 said:
Do you know where i can purchase this piece because i am not having any luck on the interwebs
Click to expand...
It was from my supply house, they were a Siemens/Murray distributor.

Looks like you could replace one of those neutral lugs with a double lug. If not, you can add another lug beside it. Since the lug and neutral are directly to the can, adding a lug would also be bonded. You say it's on brick and you can't drill & tap, but you can. Just drill the hole to be tapped and before you tap it, use a masonry bit the same size, or a little smaller, as the metal bit and drill you a cavity for the lug screw to go into.
Worse case, use a punch and make a divet in the brick to allow the screw to run into.
 
alyoshak24 said:
BACKGROUND - Installing Grounding Electrode System for a 2 story 2 tenant house in Chicago each floor having a corresponding meter. After Driving 2 ground rods 8 ft apart from each other and running my green #8 to the meter enclosure, i attempted to terminate into the grounding lug (which is usually below or adjacent to the grounded lug of meter box and usually smaller than the grounded lug) but this meter enclosure, which is older ring style, does not have that adjacent grounding lug. This is getting expected next week and need to reconcile this issue; my question to the Masters/Experts nationwide is:

  • Can i terminate the GEC to the load side neutral lug of either meter can ? if not then ~

  • Can I terminate the GEC to the grounding bushing on either of the 1/2 or 3/4 EMT grounding bushings and leave it at that since the Neutral lug is bonded to the meter enclosure? if not then ~

  • Since it is mounted on brick, drilling and tapping is out of the question, is there a GEC lug kit for this MURRAY model double ring meter can (Retrofit code compliant GEC Kits) ? if there arent then ~

  • what do i do in this situation of 1 - 3 are not an option or against code ?
** Upgrading/changing out double ring Murray meter box to a new double ringless or ring meter box is not an option **

**** Can you please provide NEC excerpts/sources sited or supplemental YouTube vids or pics of your guys work how you got a similar situation to work out. ****

THANK YOU MAESTRO'S
Click to expand...


According to the NEC, the grounding electrode conductor (GEC) must be connected to the grounding electrode system, which includes the ground rods, and to the grounded service conductor at the service equipment or at the source of a separately derived system.

In the case where there is no grounding lug in the meter box, it is not recommended to terminate the GEC to the load side neutral lug of either meter can. It is also not recommended to terminate the GEC to the grounding bushing on either of the 1/2 or 3/4 EMT grounding bushings, as this would not provide an adequate connection to the grounding electrode system.

One possible solution would be to install a separate grounding lug on the meter box or on the adjacent wall, using an approved grounding lug kit. This lug would need to be connected to the grounding electrode system and the GEC would be connected to this new grounding lug.

Another option would be to install a ground bar in the meter box or adjacent to it, and connect the GEC to this ground bar. However, this would require the approval of the local AHJ (Authority Having Jurisdiction).

In any case, it is important to follow local codes and regulations and to obtain approval from the AHJ before making any changes to the grounding system. The NEC reference for this information is 250.50, 250.52, and 250.70.
 
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