NOJA Power's ACR Relay Firmware

NOJA Power announces the release of Relay 1.12, an upgraded firmware platform for its OSM series automatic circuit reclosers (ACRs). Among other enhancements, the firmware includes sectionalizer functionality, dynamic directional protection, live-load blocking, additional logic channels and remote battery test.

The addition of sectionalizer functionality to the Relay 1.12 firmware platform enables utilities to configure the ACR as a conventional recloser, a sectionalizer or to function as either device depending on the type of fault. The ACR is able to perform all three functions in either direction of the electricity feeder. To access the new functionality utilities need only upgrade to the new version of the software.

An ACR has several key advantages over a conventional sectionalizer, including limiting the duration of outages in the event of a fault, operating thousands of times under fault current loads and replacing SF6 with a solid dielectric.

Dynamic directional protection enables the ACR to react to a change in the direction of a fault even part way through a reclose operation. Previously, the ACR would commit to a complete reclose operation even if the fault changed direction during the operation. Dynamic directional protection is useful, for example, when an overcurrent occurs due to load switching. Previously, the energy dumped because the load switching in the first cycle would cause the ACR to commit to a complete reclose operation; but with dynamic directional protection, the ACR detects the energy being returned in the next cycle as a change of fault direction and terminates the reclose operation.

Live-load blocking is an advantage in situations such as when a subscriber load is lost, causing a reclose operation, and the subscriber’s back-up generator starts up. The ACR now remains open if it detects voltage on the subscriber side during the reclose operation to eliminate the risk of damage due to switching back in unsynchronized generation capacity.

Relay 1.12 also includes remote battery testing of NOJA Power’s RC10 control and communications cubicle’s uninterruptable power supply.

NOJA Power

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