Grid intertied PV house service

[George Stolz]

Anybody see any problems with this one-line?

 

[Buck Parrish]

As long as your load is less then 200. It looks good to me.
I think you can use 2/0 cu on an SFD,

 

[mxstar211]

I don't see anything to prevent backfeeding the utility due to a power-outage, but the one-line for the pv equipment isn't shown unless I missed something.

 

[mxstar211]

Forgot to add that I didn't see anything that syncs the pv to the grid either.

 

[iwire]

What is shown looks OK but there is a lot missing.

Your past the hurdle of bus capacity and two feeders.

 

[George Stolz]

Thanks for the replies!

As long as your load is less then 200. It looks good to me.
I think you can use 2/0 cu on an SFD,

Yeah, I figured, why bother. There's two panels in the house.

I don't see anything to prevent backfeeding the utility due to a power-outage, but the one-line for the pv equipment isn't shown unless I missed something.

The inverter kills the upstream if it detects a loss. Hence the two panels in the house.

Forgot to add that I didn't see anything that syncs the pv to the grid either.

That's the solar guy's problem. I bet the inverter does it itself.

What is shown looks OK but there is a lot missing.

What more would you add? I am doing just the work shown, minus Panel PDP which is installed by the solar guy. I am pulling the 60A feeders. Anything actually PV will have to be drawn on the solar detail by the solar guy.

Your past the hurdle of bus capacity and two feeders.

You just said a mouthful.

 

[iwire]

What more would you add? I am doing just the work shown, minus Panel PDP which is installed by the solar guy.

In that case nothing, I assumed your where going all the way.

You just said a mouthful.

In more ways than one. :grin:

 

[George Stolz]

One more thought. What are your thoughts on feeding one building with two feeders, knowing that one comes from the inverter and one from the utility?

 

[iwire]

One more thought. What are your thoughts on feeding one building with two feeders, knowing that one comes from the inverter and one from the utility?

Your good to go 225.30(A)(5)

 

[George Stolz]

So to go one further, I don't believe I can (or would want to) serve a geothermal heat hump on Panel C - 70A Max OCPD, 38 MCA. Agreed?

 

[iwire]

I would say no.

If I was being asked to I think I would want to talk to the inverter manufacturer to see if their unit has the sack to start a compressor that large.

The inverters I have worked with will just take themselves off line if overloaded.

 

[George Stolz]

I think "no" is the easiest answer. I think a reasonable emergency run time for the lights and receps for daily life would be of more service than heating, if the house winds up as madly green as they are pining for. I doubt they'll spend much time without power, it's close to town.

 

[iwire]

Are there batteries involved here?

If not there is no power during an outage, the PV shuts down.

 

[George Stolz]

Yeah, there's batteries. And a generator ties into the inverters too. I think there's a few donkeys on treadmills in the wings, too.

 

[iwire]

Yeah, there's batteries. And a generator ties into the inverters too. I think there's a few donkeys on treadmills in the wings, too.

Well put.:grin:

Having batteries with a grid tied system is just ridiculous. Trying to drive a heat pump from batteries ...... well sure if you have a free supply of batteries but otherwise no ..... :grin:

 

[George Stolz]

The bad news about the heat pump didn't go over well initially, but eventually I remembered there are two fireplaces in the house. That softened the news.

So far, the utility has taken a peek and suggested that I am missing a disconnect, which the rep says is not required by him and that he wouldn't miss it but that he thinks it's required by the NEC, and deferred to the AHJ about that.

I did a little bit of poking around and came up with 690.13, but I'm not sure if that should be in my scope of work or not. I'm thinking not.

Panel PDP is right inside the entry door of the detached garage and has disconnects for just about everything. You think this panel complies with 690.13?

 

[iwire]

It has been my experience that the POCO will require a visible break disconnecting means at a location of their choosing.

 

[George Stolz]

Disconnecting what from what though?

 

[iwire]

The AC from the inverter to the grid.

Here is the wording from a local power company.

External Disconnect Switch: For Listed inverters, the Company may require an external disconnect switch (or comparable device by mutual agreement of the Parties) at the PCC with the Company or at another mutually agreeable point that is accessible to Company personnel at all times and that can be opened for isolation if the switch is required. The switch shall be gang operated, have a visible break when open, be rated to interrupt the maximum generator output and be capable of being locked open, tagged and grounded on the Company side by Company personnel. The visible break requirement can be met by opening the enclosure to observe the contact separation. The Company shall have the right to open this disconnect switch in accordance with this Interconnection Tariff.

 

[George Stolz]

Wow, that's pretty harsh, a breaker wouldn't do there. In my setup, panel PDP is pretty intimidating, but the main panel is very straightforward. Main Service Disconnect is the main breaker, inverter is at the bottom.

According to the guy at the POCO, then a lockable panel cover is good enough for them. As the solar gal put it, "As if the linemen are going to drive the streets looking for PV panels, and shut each of them down and lock them out. :roll: "

I haven't heard back on my last round of questions from the AHJ or the POCO, so I guess I'll be bugging them tomorrow. My beautiful re-bid window is closing, and I need some conclusive answers PDQ.