ideal setup for 3 Phase 208V 43.2KW SolarEdge Inverter 175-200 OCPD

hevnbnd

Member
New install for myself. Looking at using this new 43.2KW SolarEdge Inverter on 3 Phase 208V. Here is a link to the specs.
https://d3g1qce46u5dao.cloudfront.net/data_sheet/se_three_phase_commercial_inverters_for_208v_ds_na_data.pdf

I suspect a supply-side tap is the only option. Per manual OCPD is 175A. However it states "You may use a larger size than recommended but never above 200A.

This is a new install with underground service coming. I was thinking service to meter. Meter to Tap to outside disconnect.

So my question is what is the cleanest setup? Any photos of 3 phase install?
 

hevnbnd

Member
Let me rephrase my question.

I have talked to my local supply house and they are not real familiar with solar installation. We are in a small town and I believe I have like the 3rd Solar installation in town.

I am trying to figure out what the best outside equipment to use. IE I could use a Polaris-Style connector to make the tap between the meter and my main outside disconnect in a junction box or if their is a cleaner installation method then I would like to use it.

What I thought would be nice was if I could find a 400A disconnect that had terminals where I could tie in my solar instead of using a tap.
 

jaggedben

Senior Member
We need some info about the existing service that you're tying into. A supply side tap with polaris to a fused disco is certainly one way these things get done. But you've given no info to confirm feasibility, nor to rule out a load side connection. If you were to tap between meter and existing main, where/how would you do it? What are ratings of the existing equipment?

You seem to be overestimating the circuit current, too. Spec sheet says 120A per phase, which would mean a 150A OCPD.
 

hevnbnd

Member
We need some info about the existing service that you're tying into. A supply side tap with polaris to a fused disco is certainly one way these things get done. But you've given no info to confirm feasibility, nor to rule out a load side connection. If you were to tap between meter and existing main, where/how would you do it? What are ratings of the existing equipment?

You seem to be overestimating the circuit current, too. Spec sheet says 120A per phase, which would mean a 150A OCPD.
Thanks for the reply. Currently there is no existing service. We are tearing out the overhead delta 3 Phase and installing underground 208V 3 Phase. All wiring inside building is getting replaced as well. So I have a clean slate to work with.

I got the 175 from this part of the SolarEdge manual.

2018-08-26.jpg
 

electrofelon

Senior Member
One thing I have done for a supply side connection is installed a 320/400 amp meter socket. This gets you your two sets of lugs, one for the regular loads and one for the solar. Even though the class 320 socket is larger, I find it "cleaner" overall than installing a wireway or box somewhere to make the tap.
 

jaggedben

Senior Member
I see now that you mentioned a new service in your first post.

It would still be useful to know what the load requirements on the building are. (Is 400A your building load?) Broadly speaking, your solar could be done at the opposite end of a main panelboard or switch board if it is rated 900A or more. There are probably other scenarios (e.g. 600A rated busbar with 400A OCPD) where it could work, but again specifics depend on the buildng load requirement. I'm not sure I'd bother with a supply side connection if one of these scenarios is easily feasible.

Regarding your idea of a 400A disconnect with multiple lugs ; you would need another fused disconnect for the solar. Consider whether a tap box and two service diconnects would be a cleaner solution. While I have done taps inside an exiting main disconnect many times, some AHJs might ask 'Why did you bring the solar into the main disconnect when you had a chance to keep them separate on a new service?"

That's an interesting page of the SolarEdge manual, but I think per code you are still only required to provide a 150A output circuit and OCPD. That's what will figure into article 705 calculations.

Read Article 705 carefully in your relevant code cycle.
 

hevnbnd

Member
One thing I have done for a supply side connection is installed a 320/400 amp meter socket. This gets you your two sets of lugs, one for the regular loads and one for the solar. Even though the class 320 socket is larger, I find it "cleaner" overall than installing a wireway or box somewhere to make the tap.
Thanks. That was exactly what I was looking for. I will see if they can get me a MilBank to fit the bill.
 

jaggedben

Senior Member
One thing I have done for a supply side connection is installed a 320/400 amp meter socket. This gets you your two sets of lugs, one for the regular loads and one for the solar. Even though the class 320 socket is larger, I find it "cleaner" overall than installing a wireway or box somewhere to make the tap.
:thumbsup: ...assuming the facility doesn't require a CT meter.

I was going to mention that, too, and then I forgot. :slaphead:
 

hevnbnd

Member
I like the ideal of a 600A rated busbar with 400A OCPD also. This would allow me to use a breaker in main panel as my disconnecting means instead of a disconnect outside. My local PO allows us to waive the requirement for the manual disconnect switch.

To prevent a net metering customer from back-feeding a de-energized line, the customer
shall install a manual disconnect switch with lockout capability that is accessible to
Company personnel at all hours. This requirement for a manual disconnect switch will be
waived if the following three conditions are met: 1) The inverter equipment must be
designed to shut down or disconnect and cannot be manually overridden by the customer
upon loss of Company service; 2) The inverter must be warranted by the manufacturer to
shut down or disconnect upon loss of Company service; and 3) The inverter must be
properly installed and operated, and inspected and/or tested by Company personnel
 

ggunn

PE (Electrical), NABCEP certified
One thing I have done for a supply side connection is installed a 320/400 amp meter socket. This gets you your two sets of lugs, one for the regular loads and one for the solar. Even though the class 320 socket is larger, I find it "cleaner" overall than installing a wireway or box somewhere to make the tap.
Most if not all the AHJ's I work with will not allow any connections other than their own inside their revenue meter can.
 

ggunn

PE (Electrical), NABCEP certified
bummer then you cant run service entrance conductors out of the meter :( I guess no power for those people.
You know what I mean, though, right? They allow no line side PV connection in their revenue meter can or CT enclosure.
 

electrofelon

Senior Member
You know what I mean, though, right? They allow no line side PV connection in their revenue meter can or CT enclosure.
So they allow 230.40 exceptions 1,2,3, and 4 but not 5? That doesn't make much logical sense. Could you put a light or recep on it to make it an exception 2 or 3 install?
 

ggunn

PE (Electrical), NABCEP certified
So they allow 230.40 exceptions 1,2,3, and 4 but not 5? That doesn't make much logical sense. Could you put a light or recep on it to make it an exception 2 or 3 install?
I haven't tried any sort of end run around their policies; they just say no and we obey. Except for CPS (San Antonio) they all allow IPC connections to the service conductors in the MDP, so that's pretty easy. Most of them, anyway; one of them allows no supply side interconnections, period.
 

pv_n00b

Senior Member
So they allow 230.40 exceptions 1,2,3, and 4 but not 5? That doesn't make much logical sense. Could you put a light or recep on it to make it an exception 2 or 3 install?
The local muni utility in my town says no PV supply-side interconnections, and that's the end of the discussion with them. Never been a supply-side interconnection here and they have PV systems from residential up to I think 700kW commercial. All load-side.
 

pv_n00b

Senior Member
New install for myself. Looking at using this new 43.2KW SolarEdge Inverter on 3 Phase 208V. Here is a link to the specs.
https://d3g1qce46u5dao.cloudfront.net/data_sheet/se_three_phase_commercial_inverters_for_208v_ds_na_data.pdf

I suspect a supply-side tap is the only option. Per manual OCPD is 175A. However it states "You may use a larger size than recommended but never above 200A.

This is a new install with underground service coming. I was thinking service to meter. Meter to Tap to outside disconnect.

So my question is what is the cleanest setup? Any photos of 3 phase install?
If you are doing a new service entrance I recommend going for a load side interconnection. For me, supply side is something you do if there is no other possible way to do a load side.
 

ggunn

PE (Electrical), NABCEP certified
If you are doing a new service entrance I recommend going for a load side interconnection. For me, supply side is something you do if there is no other possible way to do a load side.
"No other possible way" is a pretty broad concept. For me, a full MDP is reason enough.
 

ggunn

PE (Electrical), NABCEP certified
One person's "no possible way" is another person's "hold my beer and watch this." :D
I don't drink beer at work (not usually, anyway :D), but of the hundreds of residential PV systems I have designed, I'd wager that a good 15% are supply side interconnected. It's not a big deal.
 
Top