310 BLAZE IT
Senior Member
- Location
- NJ
I am very familiar with section 705 so I want to steer this post away from reviewing those code requirements. Perhaps this discussion goes beyond code since code only gives requirements for the rating of busbars in 'Panelboards'.
Since many utilities require cold sequence metering, where a connection on the supply side of the service disconnect is prohibited due to net metering requirements, I am looking for a way to connect on the load side in a way that ensures the bus is protected. Reducing the main breaker to a smaller size, connecting on the opposite end of the busbar, and increasing the bus rating beyond the main breaker rating are all not options here.
Has anyone run into this and determined the best way of adding differential protection? I am thinking that I will need CTs after the meter and on the PV breaker and will need to use an SEL relay protection with an RTAC unit to temporarily curtail the PV Intervters. I was thinking of using an SEL 587 but I don't see any relay specific for this application so I'm not too confident with this application.
Anyone have experience with this?
Thanks,
Since many utilities require cold sequence metering, where a connection on the supply side of the service disconnect is prohibited due to net metering requirements, I am looking for a way to connect on the load side in a way that ensures the bus is protected. Reducing the main breaker to a smaller size, connecting on the opposite end of the busbar, and increasing the bus rating beyond the main breaker rating are all not options here.
Has anyone run into this and determined the best way of adding differential protection? I am thinking that I will need CTs after the meter and on the PV breaker and will need to use an SEL relay protection with an RTAC unit to temporarily curtail the PV Intervters. I was thinking of using an SEL 587 but I don't see any relay specific for this application so I'm not too confident with this application.
Anyone have experience with this?
Thanks,