Best MSP for 80A PV?
- Thread starter Zee
- Start date
curt swartz
Electrical Contractor - San Jose, CA
- Location
- San Jose, CA
- Occupation
- Electrical Contractor
You are not going to be able to install a 80 amp PV breaker into a CSED that has a 200 amp main breaker even if it has a 225 amp buss. You would need to replace the 200 amp main with a 175 amp breaker.
PWDickerson
Senior Member
- Location
- Clinton, WA
- Occupation
- Solar Contractor
I'll bite. I would spec a Milbank U5854-PXL-200 meter-main without any bussing for branch breakers. That would feed a Square D HOM4080M200PC main panel in the garage, and I would tap the 4/0 AL feeders to a breaker enclosure next to the meter-main, and that would feed a 100A 6-space AC combiner panel next to the inverter in the garage with two 40A breakers for the inverters. If your utility requires a visible break disconnect, you will need to use a fused knife switch instead of a breaker enclosure. And of course most regions don't use ring-type metering equipment like we do here, so you will need to figure out the equivalent ringless model. I can't wait until PCS becomes widely available making line-side and feeder taps a thing of the past.
jaggedben
Senior Member
- Location
- Northern California
- Occupation
- Solar and Energy Storage Installer
I thought Siemens had one with the 'parallel energy disconnect' in a separate compartment, i.e. 2020 NEC compliant. But maybe that's only the 400A versions.
I like the 175A breaker idea, almost no one actually uses 48kW. Otherwise, it's going to be in essence either a supply side tap or a load side tap.
I like the 175A breaker idea, almost no one actually uses 48kW. Otherwise, it's going to be in essence either a supply side tap or a load side tap.
right, thx. (175A main brkr and 225A bus will allow 95A of PV.)
Which panel(s) have a 225A bus? (That also allow easy placement of line side CT coils for consumption monitoring)
All the centerfed panels and backfed main breaker panels (4-pole backfed main brkr.) dont have space to place CT's.
Thank you. That will work.
And I may just do that.
However, was hoping for a combo MSP, instead of separate meter and separate SP.
I agree with the small 100A combiner panel as the ACD. We dont need visible blade here.
I will need it also as the required INV ACD "within line of sight of INV's" .....as INV's are in garage and MSP outside.
Thanks.
Just checked:
Actually they have many options with a separate PV breaker spot (separate from main bus) that is line side. 40A to 200A of PV depending on model.
It is just the CT coils that are a pain as these Siemens panels all have that 4 pole backfed brkr that is impossible to access.
Last edited:
wwhitney
Senior Member
- Location
- Berkeley, CA
- Occupation
- Retired
If "combo SP" means meter/main/distribution all in one panel, I would say that is much less flexible, even though it seems to be standard here in CA. Adding a feeder between the main breaker and the distribution allows for doing a feeder interconnection, as PW Dickerson observed. It also simplifies installing any future ESS with backup (MID). So put me down as also voting for a meter/main only next to a separate distribution panelboard (which if MLO should have provisions for adding a main breaker).
Cheers, Wayne