I'm trying to add battery storage (highlighted in yellow on the screenshot below) to my existing grid-tied solar installation with the primary goal to mitigate demand fees during peak time.
You can see that discussion in a separate topic:
diysolarforum.com
SRP (the utility company) has this diagram for cases similar to mine:
They require the ATS (Automatic Transfer Switch) to be installed, preventing backfeed to the grid from Solar or battery storage.
The requirements for the ATS are the following:
Based on them it looks like any ATS on the market certified with UL-1008 would do that job by disconnecting the DER system from the grid if the latter goes down. E.g. "Generac RXW200AZ."
But I want also to be able to hook up a portable generator to that ATS in case of emergencies. E.g. long dark rainy nights with power outages, no sun, and depleted battery bank.
I read the documentation for "Generac RXW200AZ." It requires a "Generac" brand name generator ($$$) and will NOT support a "no-name" portable generator that I have. While it might disconnect my DER system from the grid during a power outage (meeting the SRP requirements), it will NOT activate the generator input even if the voltage from the generator has been detected unless it's a "Generac" brand.
I look at the other brands and models of ATS. All of them (as I found on the market so far) would require a generator matching their brand.
My questions to the community in this forum:
Which brand/model of the ATS could meet my needs?
The criteria are the following:
You can see that discussion in a separate topic:
Mitigation of demand from utility with solar
Hi. I'm from Phoenix, AZ with 12.96kW grid-tied system up and running. It has 5 strings of panels and two SMA grid-tied inverters working in parallel. They are AC coupled before solar meter. It's a standard design recommended by SRP (utility company) published on their Web-site I'm on "Customer...
diysolarforum.com
SRP (the utility company) has this diagram for cases similar to mine:
They require the ATS (Automatic Transfer Switch) to be installed, preventing backfeed to the grid from Solar or battery storage.
The requirements for the ATS are the following:
Based on them it looks like any ATS on the market certified with UL-1008 would do that job by disconnecting the DER system from the grid if the latter goes down. E.g. "Generac RXW200AZ."
But I want also to be able to hook up a portable generator to that ATS in case of emergencies. E.g. long dark rainy nights with power outages, no sun, and depleted battery bank.
I read the documentation for "Generac RXW200AZ." It requires a "Generac" brand name generator ($$$) and will NOT support a "no-name" portable generator that I have. While it might disconnect my DER system from the grid during a power outage (meeting the SRP requirements), it will NOT activate the generator input even if the voltage from the generator has been detected unless it's a "Generac" brand.
I look at the other brands and models of ATS. All of them (as I found on the market so far) would require a generator matching their brand.
My questions to the community in this forum:
Which brand/model of the ATS could meet my needs?
The criteria are the following:
- 240V/200A single phase
- UL-1008 certified
- Automatically disconnects from the grid if the latter goes down before reconnecting to the generator (open transition "break-before-make")
- The generator connection in the ATS should activate by detection of the voltage in the generator inlet without communication to the generator. Or it can be done automatically after disconnection from the failed grid waiting for the generator to be started manually
