Series: AF0500

The AF0500 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. Any combination of point and fiber-optic sensors can be connected to the relay to provide maximum protection. The AF0500 accepts PGA-LS10 point sensors and PGA-LS20/PGA-LS30 fiber-optic sensors. Sensors, inputs, and connections are monitored to ensure fail-safe operation. LEDs on the relay and on the sensors indicate sensor health and which sensor(s) detected an arc fault. A secondary solid-state trip circuit provides a redundant trip path. The AF0500 relay includes an Ethernet interface and supports Modbus® TCP communication. Zone tripping, upstream breaker tripping, and tie-breaker tripping applications can be easily configured. A USB port is used for configuration and access to event logs. This series is well suited for switchgear, transformer, and power converter applications.

Sensor Placement

The AF0500 arc-flash relay and sensors are easily installed in retrofit projects and new switchgear with little or no re-configuration. Simple applications work straight out of the box with no need for PC 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.