The service (Electrical Panel 120/240 volt High Leg) available on-site is an open-delta configuration which only utilizes 2 transformers and provides a 3-phase service (L1 to L2=240V, L2 to L3=240V, L1 to L3=240V, and L1 to Ground=120V, L2 to Ground=208V, L3 to Ground=120V). The FRONIUS -Symo advance (12.0-3, 208-240) has a provision for a High Leg grid connection.
But now the Utility company is saying - The inverter that was selected is a 3-phase 240V connection, but the service transformer is an open delta (2 phase). A 3-phase inverter is not allowed to be on an open-delta transformer. If you choose to install a 3-phase inverter, the open delta bank will need to be closed, and the report will include the cost to upgrade it to a 3-phase closed delta bank with the 3rd transformer can being large enough to support this application. If you choose to install a single-phase inverter, the existing transformer can will need to be upgraded to support this application unless this application is downsized enough to avoid the upgrade.
Could you please advise on this situation? Any suggestion will be highly appreciated. Thanks in advance.
But now the Utility company is saying - The inverter that was selected is a 3-phase 240V connection, but the service transformer is an open delta (2 phase). A 3-phase inverter is not allowed to be on an open-delta transformer. If you choose to install a 3-phase inverter, the open delta bank will need to be closed, and the report will include the cost to upgrade it to a 3-phase closed delta bank with the 3rd transformer can being large enough to support this application. If you choose to install a single-phase inverter, the existing transformer can will need to be upgraded to support this application unless this application is downsized enough to avoid the upgrade.
Could you please advise on this situation? Any suggestion will be highly appreciated. Thanks in advance.