Series: PGR-8800

The PGR-8800 series arc-flash relay is a microprocessor-based protection relay that limits arc-flash damage by using light sensors to rapidly detect an arc and then trip a circuit breaker. Phase-current-transformer inputs are provided for current-constrained, arc-flash protection and, when so equipped, a programmable definite-time overcurrent function can be enabled. An optical sensor on the PGR-8800 and an adjustable trip-level reduce the chance of nuisance tripping by setting a threshold for ambient light. The PGR-8800 accepts PGA-LS10 point sensors and PGA-LS20/PGA-LS30 fiber-optic sensors, which are designed to collect light over a wide angle and with high sensitivity. Sensors, inputs, and connections are monitored to ensure fail-safe operation. A secondary solid-state trip circuit provides a redundant trip path. A USB port is used for configuration and access to event logs and graphs. For fast fault location, front-panel and sensor LEDs indicate sensor health and which sensor(s) detected an arc fault. A maximum of four PGR-8800 units can be linked into one system.

Sensor Placement

The PGR-8800 arc-flash relay and sensors are easily installed in retrofit projects and new switchgear with little or no re-configuration. More complex systems with multiple power sources are configured using the relay’s built-in USB interface software. Generally, it is recommended to mount one or two sensors per cubicle to cover all horizontal and vertical bus bars, breaker compartments, drawers, and anywhere that there is a risk for an arc fault. Threading a fiber-optic sensor through the cabinets and in areas where point-sensor coverage is uncertain results in complete coverage and an added level of redundancy. Even if policy is to only work on de-energized systems, all maintenance areas should be monitored to prevent potential damage and additional cost.