Temperature rating of a 200A meter socket terminal

[James Williams]

I've got a UL listed 200A 1ø meter socket I will use in a feeder to an art studio building fed from my house. The feed will be #2 AL URD. It has a 100A rating at 90°C and I want to feed it from a 100A breaker.

The meter socket label is not marked with a temp rating for the terminals, and the terminals (ILSCO D3845) are not marked with a rating either. The cut sheet and instructions from Siemens have no temp rating listed. I googled and found several POCOs that specify 90°C as part of their meter socket specifications. Googling ILSCO D3845 produces no relevant response.

Is it OK to assume a 90°C rating?
I also assume that most everything POCO-related is 90°C anyway.

 

[infinity]

Is it OK to assume a 90°C rating?

I would say no don't assume anything. Do you have an literature that shows the rating?

 

[James Williams]

I would say no don't assume anything. Do you have an literature that shows the rating?

As stated in the original post: no temperature rating found
1: on the label inside the meter socket
2: in the downloaded cut sheet
3: in the downloaded instructions
4; on the lugs
The socket is NOS and I don't have any paperwork issued with it (if there ever was any). That's why I downloaded it from the Siemens site.

The fact that POCO conductors, both overhead and underground, always appear to be undersized when compared to NEC requirements and the 90°C temperature from random POCOs' meter socket specifications lead me to conclude that 90°C is kosher.

I'm really looking for someone with POCO experience to say yes or no.

 

[don_resqcapt19]

URD, without other markings, is not a permitted NEC wiring method. Where are you finding a 100 amp breaker marked for use with 90°C conductors?

 

[curt swartz]

No low voltage equipment is listed to 90C terminations. Even if the meter socket was the circuit breaker is not.

 

[electrofelon]

Basically you have 3 options:
1. #2 with a 90A breaker
2. #1 with a 100A breaker
3. Use #1 AL (or #3 CU) for the termination to the equipment, and splice it to the #2 (using a 90 degree splicer, but nearly all are). It isn't exactly clear what length you need before making the transition to the smaller conductor,. But many say a separate enclosure or like 3 ft because that is the conditions they use when evaluating the equipment.

 

[wwhitney]

IIRC correctly when I checked the UL listing standards for meter sockets and for meter mains, it specified that 75C terminals are the default, and that if the meter socket has 90C terminals, it is to be so labeled. 90C terminals would be useful on the line side, and could be useful on the load side if the next piece of equipment isn't a breaker.

Cheers, Wayne

 

[Hv&Lv]

old post but.

90C terminations

I was sent a private message asking about the use of 90C insulation and why it must always be applied to equipment based on the 75C column of NEC tables. I think the answer would be of value to many people, so I am replying in the Form. The primary reason is the way UL tests temperature rise...

forums.mikeholt.com

 

[James Williams]

Menards sells 2-2-4 URD, which is also rated RHH, RHW-2, and USE-2. RHW-2 gives a 90°C rating in wet conditions. It is currently $1.69/ft. I buy enough to untwist the excess and produce the 3rd CCC. I'd use the yellow stripe "neutral" as the EGC.

Ok, so here is the plan:
1: 100A 75°C breaker in house
2: length of #3 CU to junction box
3: splice to #2 URD/RHW-2 AL in junction box
4: run through 90°C PVC to meter socket on studio
5: land on line terminals
6: from load terminals of meter socket length of #3 CU to 75°C 100A breaker line terminals (as "Emergency Disconnect")
7: from load terminals of CB length of #3 CU to junction box
8: splice #3 to #2 URD/RHW-2 AL in junction box
9: run through 90°C PVC
10: in junction box splice to #3 CU
11: connect to main breaker.

I'll have to run the numbers on this versus larger conductors. #3 CU is much, much more expensive at 4 ea @$2.14/ft. The total run is > 130 feet.

 

[curt swartz]

Why not use (3) #1 XHHW and (1) #6 AL XHHW conductors? It will be less expensive than buying 2 runs of the cable you are proposing and no J-boxes or splices required.

Even using (3) #3 and (1) #8 copper conductors will be less expensive than the cost of J-boxes and connectors to splice the cables.

 

[James Williams]

Called Siemens Tech Support. They say 75°C