Convert split service to single main breaker?

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jaggedben

Senior Member
Location
Northern California
Occupation
Solar and Energy Storage Installer
I think the logic is that they don't make NM bigger than 2/3. And SER or something like that would look different. The cables with the solid color red are NM. The one with the red stripe on the black is probably SER.
 
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ramsy

Roger Ruhle dba NoFixNoPay
Location
LA basin, CA
Occupation
Service Electrician 2020 NEC
Why do you want to change them?
The disconnects are located in a single location and appear to be wired correctly.

A single 200 breaker would require each feeder to be increased to 200 amp.
I vote don't fix it, if its not broken.
240.21(6)(H) may allow the OCP for battery storage to be located in the battery room.
 

ramsy

Roger Ruhle dba NoFixNoPay
Location
LA basin, CA
Occupation
Service Electrician 2020 NEC
Neither panel is going to be listed for a single 200 amp breaker even if they would physically fit. There are no neutral terminations for "200 amp" wire either. Its time to break stucco!

Also whoever installed those 125 amp breakers needs to stop doing electrical work. 2/3 NMB has an ampacity of 95 amp and needs to be protected at 100 amps or less.
See bottom right side of attached Southwire chart "Amperage Allowance for 3-Wire Single Phase Dwelling Service"

Notice The 125A service rating (Amps) for #2 NM. Southwire appears to be applying the next size up OCP for 104A, per 310.15(B)(7)(2) or 125A x 0.83

If battery storage OCP is allowed in battery room, per 240.21(6)(H), then existing meter center can remain un-molested, with same 125A OCP's on #2 NM, per Romex manufacturer listing.
 
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Zee

Senior Member
Location
CA
See bottom right side of attached Southwire chart "Amperage Allowance for 3-Wire Single Phase Dwelling Service"

Notice The 125A service rating (Amps) for #2 NM. Southwire appears to be applying the next size up OCP for 104A, per 310.15(B)(7)(2) or 125A x 0.83

If battery storage OCP is allowed in battery room, per 240.21(6)(H), then existing meter center can remain un-molested, with same 125A OCP's on #2 NM, per Romex manufacturer listing.
Interesting on ampacity of #2.

We want to back up whole house. Cannot feed two circuits with MID (Solaredge Back Up Interface). Must connect to ONE circuit.
 

curt swartz

Electrical Contractor - San Jose, CA
Location
San Jose, CA
Occupation
Electrical Contractor
See bottom right side of attached Southwire chart "Amperage Allowance for 3-Wire Single Phase Dwelling Service"

Notice The 125A service rating (Amps) for #2 NM. Southwire appears to be applying the next size up OCP for 104A, per 310.15(B)(7)(2) or 125A x 0.83

If battery storage OCP is allowed in battery room, per 240.21(6)(H), then existing meter center can remain un-molested, with same 125A OCP's on #2 NM, per Romex manufacturer listing.
Since there are 2 feeders neither of them supply the total load to the dwelling so the 83% allowance can not be used. Manufacture listings can not override minimum NEC requirements.
 

ggunn

PE (Electrical), NABCEP certified
Location
Austin, TX, USA
Occupation
Electrical Engineer - Photovoltaic Systems
Neither panel is going to be listed for a single 200 amp breaker even if they would physically fit. There are no neutral terminations for "200 amp" wire either. Its time to break stucco!

Also whoever installed those 125 amp breakers needs to stop doing electrical work. 2/3 NMB has an ampacity of 95 amp and needs to be protected at 100 amps or less.
Can't they get away with it if the subpanels are the sole electrical supplies on separate buildings?
 

ramsy

Roger Ruhle dba NoFixNoPay
Location
LA basin, CA
Occupation
Service Electrician 2020 NEC
Since there are 2 feeders neither of them supply the total load to the dwelling so the 83% allowance can not be used. Manufacture listings can not override minimum NEC requirements.
Roger that, existing permit records may show separate services, before some remodel merged the building, or inspector missed it.

Either way, if the building doesn't already have Open Permits, its does now.

Anyone who touches that crap will own it.
 

Mr. Serious

Senior Member
Location
Oklahoma, USA
Occupation
Electrical Contractor
any help in identifying the manufacturer of the panel in the 3rd and 4th photo (upside down breakers) is greatly appreciated.

If you think that bottom 90-amp breaker is the original one, maybe it is Crouse-Hinds? I've seen breakers with a similar style and a Crouse-Hinds label.
 
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Zee

Senior Member
Location
CA
If you think that bottom 90-amp breaker is the original one, maybe it is Crouse-Hinds? I've seen breakers with a similar style and a Crouse-Hinds label.
May be ITE/Gould. That would also correspond to the more recent Siemens/Murray breaker above it.
 
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