Adding gridtie only Solaredge to Generac generator

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Zee

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Can I connect a grid tie (no battery) inverter to this home which already has a Generac generator? 22 kW GENERAC GUARDIAN

Where would you connect an SE11400H-US inverter?
2p60 brkr in MSP.....inside Generac Emergency Disconnect box.....line side tap....other.....impossible?

1.jpg2.jpg3.jpg20200529_122445.jpg20200529_122813.jpg20200529_122818.jpg20200529_122904.jpg
 
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(I dont need the solar to work in an outage. I just don't want to fry the generator or anything)
 
Since you do not want any chance of the PV operating while connected to the generator, the best configuration is to connect the PV backfeed to the POCO side of the transfer switch.
Unfortunately that is usually impossible when you have a meter/main with internal bussing of the POCO feed. One option is to connect a contactor on the PV backfeed that opens when the transfer switch is operated. Running the contactor off the POCO power is not sufficient to assure this, and again is not an option with a meter/main.
 
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Aha.
So I see three options:

1. Is the transfer switch the box in pics 4-6?
Can I connect the solar in there? Asking from both an NEC/AHJ and a physical perspective? I didn't look at guts of that box, so am wondering if terminals exist to land PV???
Wouldn't that be a way to avoid making the PV POC in the MSP?

2. Yes, the internal bussing of most MSP's makes it impossible to do a supply side tap. (legally and/or physically)
There is an option with this utility, a Green Meter Adapter (GMA). It circumvents the bussing inside the panel completely. I tie right into the meter socket.
Good idea here?
(i will do so if only or best option, but it does cost $1000)

3. The contactor stuff is above my head :unsure: Thanks though!
 
Is the generator connected to MSP at breaker positions 6 and 7 in pic 3? (two green led lights)
 
Zee said:
Is the generator connected to MSP at breaker positions 6 and 7 in pic 3? (two green led lights)
Click to expand...
That looks like an Eaton surge protector.
GoldDigger said:
One option is to connect a contactor on the PV backfeed that opens when the transfer switch is operated. Running the contactor off the POCO power is not sufficient to assure this, and again is not an option with a meter/main.
Click to expand...
It appears that the Generac box has a 200 amp breaker as the service disconnect and it provides the utility power input to the internal transfer switch. It's likely that there's an auxilliary contact on the transfer switch that would indicate when the switch is in the utility position. If so that could be used to activate the contactor for PV backfeed as mentioned by GoldDigger.
It appears that the meter may be downstream of the service disconnect?
 
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Zee said:
Is the generator connected to MSP at breaker positions 6 and 7 in pic 3? (two green led lights)
Click to expand...
I doubt it. I think that's a surge protector.

You need to see the inside of that box to figure out what's going on. I suspect it's already something that's not code compliant.
 
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So I went back to site, and looked inside the 200A MSP and the (E) GENERAC Generator transfer switch box:

20200610_155510.jpg20200610_155518.jpg20200610_155616.jpg20200610_160409.jpg

pics 1-3 MSP
pic 4 trnsfr switch

What is going on with that busbar / lug connection and rubber tape situation!? You may have a point Jaggedben re lack of rules followed.

Where/how would you tie in the solar?
 
The schematics in the document at the link below look like they are similar if not the same as those for the transfer switch in your pictures:

They show auxilliary dry contacts AUX and OPT. AUX which are located on the right side of the actual transfer switch itself as shown on page 2.
If at least one of these contacts is not being used then you could use it to control a contactor to backfeed your inverter. That is, if you don't end up using the Alternative Power Source Mode mentioned by BandGap1.1eV.
By the way, the SolarEdge document says that the max power from the PV inverter should not exceed 35% of the max power of the generator to use this feature.
 
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Thanks, the contactor solution is a bit over my head, sorry!

"........SolarEdge document says that the max power from the PV inverter should not exceed 35% ....."

Good point.
So the SE solution is out then.
I have 11.2 kW of PV vs 22 kW generator.
 
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Zee said:
So I went back to site, and looked inside the 200A MSP and the (E) GENERAC Generator transfer switch box:

View attachment 2552665View attachment 2552666View attachment 2552667View attachment 2552668

pics 1-3 MSP
pic 4 trnsfr switch

What is going on with that busbar / lug connection and rubber tape situation!? You may have a point Jaggedben re lack of rules followed.

Where/how would you tie in the solar?
Click to expand...
Thats a totally illegal generator install, I would quote them on replacing the whole thing.
 
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Zee said:
...

What is going on with that busbar / lug connection and rubber tape situation!? You may have a point Jaggedben re lack of rules followed.

Where/how would you tie in the solar?
Click to expand...

Yeah that's what I was betting on. It's a violation of 110.3(b) and not a particularly safe looking one at that. I agree with tortuga. Ue solar installers can't do stuff off permit like that so now the homeowner needs to pay what it really takes to do it right. Or send them back to the generator contractor to complain.
 
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Well, if you have a meter/main that does not provide any way to interconnect a transfer switch or make a supply side PV connection because of the fixed internal busing, then clearly the only solution is to disassemble the internal busing. :(

What a literal hack!
 
Yeah...
Would you guys say just the fact that the generator wiring was bolted between the bussing and the main breaker is a code violation
or
the manner in which it was done?
(busbars bent, the inner panel cover literally flexes against the rubber taped lug that protrudes forward as installed.... big bang/short waiting to happen...)

20200610_155616.jpg
 
BTW - what would a conscientious gen. installer do? Where would you tie in gen?
I have several ideas - but want to hear yours.


You can see main breaker tight20200610_155518.jpg against meter portion of cabinet to left, no place to access service wiring between meter and main breaker.



20200610_155518.jpg
 
Zee said:
Yeah...
Would you guys say just the fact that the generator wiring was bolted between the bussing and the main breaker is a code violation
or
the manner in which it was done?
(busbars bent, the inner panel cover literally flexes against the rubber taped lug that protrudes forward as installed.... big bang/short waiting to happen...)
Click to expand...

Both. The removal of the factory busbars is the root code violation. No way to do this install without violating code. But the rest of it is just incredibly dangerous in my opinion. It looks like they used self-tappers to attach the lugs to the busbars. I mean, OMG 🤮

BTW - what would a conscientious gen. installer do? Where would you tie in gen?
Click to expand...

Conscientious would replace the meter main. Semi-conscientious would be something that could have a better-than-even chance of passing a field listing. (Actually getting a field listing would cost more than replacing that meter main, so it's not gonna happen, but at least one could do it that way on principle.) What I saw once that looked okay was crimped-on lugs with similar cross section to the bussing that was removed, torqued down with the same hardware that had been holding down that bussing. Bending any busbar anywhere, ever, would be totally off limits. And drilling it would be off limits on something this size.
 
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