Both supply side and load side interconnections

[earshavewalls]

I have a plan submitted that wishes to add to an existing ground-mounted system. They already have a supply side tap for the existing system, but now they wish to add to the system, take one existing array and add a new array to it and connect it via POC at a breaker at the main service, but are leaving the rest of the existing system on the supply side tap. I have not seen this configuration before.

The Code states use of one OR the other:
(California Electrical Code) Article 690.64: "The output of a utility-interactive inverter shall be as specified in (A) OR (B)." (A) is supply side in accordance with 230.82(6); (B) is load side.

I feel that the interconnection should be one or the other. Any input on this condition would be greatly appreciated.

 

[GoldDigger]

Well, is any individual inverter connected to both sides?
The code does not say that all inverters at a site must be connected the same way.
I would say in passing that setting them up that way would be confusing for later maintenance and would require two separate PV disconnect switches unless contactors with a common control circuit are used.

Sent from my XT1080 using Tapatalk

 

[ggunn]

I have a plan submitted that wishes to add to an existing ground-mounted system. They already have a supply side tap for the existing system, but now they wish to add to the system, take one existing array and add a new array to it and connect it via POC at a breaker at the main service, but are leaving the rest of the existing system on the supply side tap. I have not seen this configuration before.

The Code states use of one OR the other:
(California Electrical Code) Article 690.64: "The output of a utility-interactive inverter shall be as specified in (A) OR (B)." (A) is supply side in accordance with 230.82(6); (B) is load side.

I feel that the interconnection should be one or the other. Any input on this condition would be greatly appreciated.

I don't see a problem from a code standpoint because each inverter is either (A) or (B) interconnected and are as such separate systems, but the AHJ might have a problem with such an arrangement.

 

[earshavewalls]

I don't see a problem from a code standpoint because each inverter is either (A) or (B) interconnected and are as such separate systems, but the AHJ might have a problem with such an arrangement.

I just got a reply back from John Wiles. He agrees with the responses here. The only difficulty is that the local POCO requires a SINGLE disconnecting means for the entire system. I believe they will redesign to add the new system to the existing line-side connection and get rid of two proposed new subpanels they intended to use to make the original configuration.

Thanks for the input!

 

[ggunn]

I just got a reply back from John Wiles. He agrees with the responses here. The only difficulty is that the local POCO requires a SINGLE disconnecting means for the entire system. I believe they will redesign to add the new system to the existing line-side connection and get rid of two proposed new subpanels they intended to use to make the original configuration.

Thanks for the input!

I thought that might be the response from the AHJ. This couple possibly be a more economical solution, anyway.

 

[earshavewalls]

Update

Update

Well, the POCO came out and checked the plans and the actual installation and will not permit this customer to add any more PV unless they pay for a new transformer.......and they all lived....happily ever after.

Thanks for the input!