Is the physical size of the taps used counted somehow for wire capacity?

GerryB

Senior Member
I am adding a house meter to an existing 3-family house and meter set up. Ridgid conduit comes into a horizontal 3 gang meter bank in the basement. There is about an 8x10 cover where the three 3/0 copper lines come in and connect to the bus and feed the existing meters. I mounted my meter from a KO at the end where the conductors enter this meter provision. Since it is a house meter we are allowed to run as small as 30amp, I ran #6thhn.
The POCO looked at what I plan to do and approved it. I am a little concerned if the EI will have any issues. When I pulled the permit he said make sure there is enough room in the trough for the taps, but I think he was envisioning the set up where there is a trough with multiple taps to each meter. Those can get pretty crowded.
So I plan to tap the three 3/0 and the 3 #6 with insulation piercing Kup L Taps. They are about 2/5 " square. (The POCO uses them also). So if any one gets what I'm trying to do this access point has the three 3/0 come in the top and 90 into the meter lugs. That is all that is in there and it is the depth of a standard meter socket. I plan to stagger the taps.

I think I'm fine, someone could comment otherwise, my basic question was do you calculate the tap size for box fill requirements.
 

kwired

Electron manager
Location
NE Nebraska
I am adding a house meter to an existing 3-family house and meter set up. Ridgid conduit comes into a horizontal 3 gang meter bank in the basement. There is about an 8x10 cover where the three 3/0 copper lines come in and connect to the bus and feed the existing meters. I mounted my meter from a KO at the end where the conductors enter this meter provision. Since it is a house meter we are allowed to run as small as 30amp, I ran #6thhn.
The POCO looked at what I plan to do and approved it. I am a little concerned if the EI will have any issues. When I pulled the permit he said make sure there is enough room in the trough for the taps, but I think he was envisioning the set up where there is a trough with multiple taps to each meter. Those can get pretty crowded.
So I plan to tap the three 3/0 and the 3 #6 with insulation piercing Kup L Taps. They are about 2/5 " square. (The POCO uses them also). So if any one gets what I'm trying to do this access point has the three 3/0 come in the top and 90 into the meter lugs. That is all that is in there and it is the depth of a standard meter socket. I plan to stagger the taps.

I think I'm fine, someone could comment otherwise, my basic question was do you calculate the tap size for box fill requirements.
Measuring the tap devices can be a little tricky with odd shaped ones, but the rule is you can not exceed 75% of the cross section at any point of the wireway or aux gutter with conductors and other components. Staggering splices is a way to comply with this rule. Things get pretty crowded before you ever reach 75% so unless you are having trouble stuffing everything into the wireway, you have a good chance of being compliant.
 

GerryB

Senior Member
Measuring the tap devices can be a little tricky with odd shaped ones, but the rule is you can not exceed 75% of the cross section at any point of the wireway or aux gutter with conductors and other components. Staggering splices is a way to comply with this rule. Things get pretty crowded before you ever reach 75% so unless you are having trouble stuffing everything into the wireway, you have a good chance of being compliant.
Great, thanks a lot.
 
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