Learning more about 120% rule and load vs line. Where does the ability to tap line side end - at first ocpd? One of my meter feeds is external to an adjacent 200a disconnect (Q22200NRB). Does the 200a CB inside the disconnect make it an ocpd? Would changing to a knife style disconnect allow output to be line? I see fused options, are fused required?
Line Side Tap Ability
- Thread starter Cmy
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Hedges
I See Electromagnetic Fields!
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I'm doing the same thing, with a quite similar QO 200A main breaker only panel.
I think "line side" would be after the meter and before this breaker.
I have put Polaris after this breaker, fanning to multiple breaker panels and a fused visible blade knife switch as PV disconnect.
Going through SolarAPP+, one choice is "Line Side Tap", with OCP suitable for service disconnect.
This design/permitting system doesn't mention "Load Side Tap" but has other breaker panel busbar rules.
Seems to me that so long as all the breaker panels have main breakers, the presence of this extra 200A breaker doesn't introduce any issues.
I will have to inquire of SolarAPP+. As you ask, "Where does the ability to tap line side end"?
For you, obviously with a 200A breaker inside Q22200NRB, downstream connections are protected to 200A. It certainly looks like OCPD!
In my case, I run 10' of 2 awg in metal conduit to a 100A fused visible blade knife switch. That 100A fuse is OCPD for a main-lug breaker panel which will have 80A of PV backfeeding it.
I don't think an AHJ will have a problem with tapping after that breaker.
Only issue I see is terminology in the SolarAPP+ system I'm trying to use.
I think "line side" would be after the meter and before this breaker.
I have put Polaris after this breaker, fanning to multiple breaker panels and a fused visible blade knife switch as PV disconnect.
Going through SolarAPP+, one choice is "Line Side Tap", with OCP suitable for service disconnect.
This design/permitting system doesn't mention "Load Side Tap" but has other breaker panel busbar rules.
Seems to me that so long as all the breaker panels have main breakers, the presence of this extra 200A breaker doesn't introduce any issues.
I will have to inquire of SolarAPP+. As you ask, "Where does the ability to tap line side end"?
For you, obviously with a 200A breaker inside Q22200NRB, downstream connections are protected to 200A. It certainly looks like OCPD!
In my case, I run 10' of 2 awg in metal conduit to a 100A fused visible blade knife switch. That 100A fuse is OCPD for a main-lug breaker panel which will have 80A of PV backfeeding it.
I don't think an AHJ will have a problem with tapping after that breaker.
Only issue I see is terminology in the SolarAPP+ system I'm trying to use.
The utility requires a second disconnect at the inverter end where solar AC goes underground . I could hire an electrician, coordinate with utility, and replace the Square D 200a CB disconnect and with a knife type. And I have my second disconnect for the other end.
Any difference from where you are putting your tapped breaker panels and my tap also bypassing 200a main panel and going 100' to a new panel? Should the inverter panel have 150 amps or 225 amps main breaker for the 120% rule?
Any difference from where you are putting your tapped breaker panels and my tap also bypassing 200a main panel and going 100' to a new panel? Should the inverter panel have 150 amps or 225 amps main breaker for the 120% rule?
Hedges
I See Electromagnetic Fields!
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I don't think utility cares what disconnect you have at a distant inverter.
They generally want a visible blade disconnect within 10' of service entrance. They may let you slide without that, in which case they could yank your meter to isolate and you would have no power.
I've got a 100' fused disconnect near the meter. Fused because that's all I found locally for my first system (downstream of a breaker where it connected to panel.)
Fused in my new system, because connected after 200A breaker with 2 awg, and the 100A fuse is OCP feeding PV combiner panel with 80A of PV breakers (future 60A of AC coupled battery breakers as well.)
If you are going 100' to new panel, either that wire is sufficient ampacity for the (200A?) breaker feeding it, or you need metal conduit to OCP within 10' (feeder tap rule) in which case that wire can be sized to its OCP. My new panel is main lug only and 20' ~ 30' from switch. My inverters are similar distance from panel.
Need to know busbar rating and PV inverter breaker rating.
Your PV combiner panel needs to comply with one of the rules:
1) OCP or main breaker plus PV breakers must not exceed 100% of busbar rating (PV breakers can go anywhere)
2) OCP or main breaker plus PV breakers must not exceed 120% of busbar rating, and PV breakers go at far end.
3) Sum of All breakers except main/OCP for the panel, that is sum of PV and any load breakers, must not exceed 100% of busbar rating
They generally want a visible blade disconnect within 10' of service entrance. They may let you slide without that, in which case they could yank your meter to isolate and you would have no power.
I've got a 100' fused disconnect near the meter. Fused because that's all I found locally for my first system (downstream of a breaker where it connected to panel.)
Fused in my new system, because connected after 200A breaker with 2 awg, and the 100A fuse is OCP feeding PV combiner panel with 80A of PV breakers (future 60A of AC coupled battery breakers as well.)
If you are going 100' to new panel, either that wire is sufficient ampacity for the (200A?) breaker feeding it, or you need metal conduit to OCP within 10' (feeder tap rule) in which case that wire can be sized to its OCP. My new panel is main lug only and 20' ~ 30' from switch. My inverters are similar distance from panel.
Need to know busbar rating and PV inverter breaker rating.
Your PV combiner panel needs to comply with one of the rules:
1) OCP or main breaker plus PV breakers must not exceed 100% of busbar rating (PV breakers can go anywhere)
2) OCP or main breaker plus PV breakers must not exceed 120% of busbar rating, and PV breakers go at far end.
3) Sum of All breakers except main/OCP for the panel, that is sum of PV and any load breakers, must not exceed 100% of busbar rating
Utility solar manager sent the solar inspector out to see what I had. Said the existing CB disconnect, next to meter, was OK but a second needed at the solar building and grid tied would be approved pending final inspection.. He did pull the meter and confirmed three lugs, one going directly to the disconnect. Kicking myself for not getting a picture of the open meter. Worst case is a 200a CB at the beginning of a 50' run to a 200a main.
With a 100a panel currently in the shop, I can run a 200a line to a new 225 amp panel with one breaker for the inverter. Breaker sized to accept Growatts 48 amps but I want panel and line able to carry higher, or added, inverter amps. May hit the lottery and go hybrid with batteries.
Solar AC leaves through the new panel/breaker, disconnect, and over to the tap on the meter disconnect line. Looks straight forward to me but no idea how many code rules I stepped on. And I thought panel watts, string size, inverter limits was the complicated part of solar.
Thanks for the help.
With a 100a panel currently in the shop, I can run a 200a line to a new 225 amp panel with one breaker for the inverter. Breaker sized to accept Growatts 48 amps but I want panel and line able to carry higher, or added, inverter amps. May hit the lottery and go hybrid with batteries.
Solar AC leaves through the new panel/breaker, disconnect, and over to the tap on the meter disconnect line. Looks straight forward to me but no idea how many code rules I stepped on. And I thought panel watts, string size, inverter limits was the complicated part of solar.
Thanks for the help.
Hedges
I See Electromagnetic Fields!
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How much total PV do you expect to eventually have?
Cheapest disconnect I've seen is meant for A/C. I think 60A, about $12 to $18.
200A blade switches can be very expensive, maybe some moderate (a few $hundred)
225A panel and 200A main breaker can have 70A PV breaker according to 120% rule. 80% continuous load is 56A. Smaller main breaker for larger PV breaker.
Running 100' of 3/0 copper wire x 3 conductors + ground, home improvement store price is $7/foot for single conductor, so $2100 plus whatever 6 gauge ground costs. Other sources about $4.50/foot, $1350. Aluminum will be less. You need 200A, not 100A which could be 2 awg given upstream OCP?
Cheapest disconnect I've seen is meant for A/C. I think 60A, about $12 to $18.
200A blade switches can be very expensive, maybe some moderate (a few $hundred)
225A panel and 200A main breaker can have 70A PV breaker according to 120% rule. 80% continuous load is 56A. Smaller main breaker for larger PV breaker.
Running 100' of 3/0 copper wire x 3 conductors + ground, home improvement store price is $7/foot for single conductor, so $2100 plus whatever 6 gauge ground costs. Other sources about $4.50/foot, $1350. Aluminum will be less. You need 200A, not 100A which could be 2 awg given upstream OCP?
Yes, before utility said CB disconnect was OK I was looking at expensive blade disconnects. Hadn't thought about solar AC out needing such a small disconnect. Target is 14kW of panels, pvwatts pushes that to the high teens. More than I need now but starting grid tied saved over hybrid. Panel prices have dropped and a $1500 Growatt 11.4k is a lot less than a Schneider pair initially recommended for $11k.
If tapping like you did, before 200a main, still has the 200a limit, guess I will use a 150a main in the new 225a panel as you suggested.
200a line from meter is ALU so I bought 130ft from Nassau Cable @ $1.89/ft. for 2/0 mains and 1awg neutral, direct burial, 233a if not in conduit. Now I realize the 200a disconnect joins ground and neutral. So I need to buy another line to tap and run ground to the new panel. Need to check size of ground wire used between disconnect and 200a main.
Shop was the first building and the 100a panel has its own ground wire. Been reading here about not having two grounds so will cut and run to to the inverter panel ground. Which in turn will go back to the taps on the meter line.
If tapping like you did, before 200a main, still has the 200a limit, guess I will use a 150a main in the new 225a panel as you suggested.
200a line from meter is ALU so I bought 130ft from Nassau Cable @ $1.89/ft. for 2/0 mains and 1awg neutral, direct burial, 233a if not in conduit. Now I realize the 200a disconnect joins ground and neutral. So I need to buy another line to tap and run ground to the new panel. Need to check size of ground wire used between disconnect and 200a main.
Shop was the first building and the 100a panel has its own ground wire. Been reading here about not having two grounds so will cut and run to to the inverter panel ground. Which in turn will go back to the taps on the meter line.
