Littelfuse's AF0100 arc-flash protection relay includes two internal trip paths for greater reliability

April 19, 2017
Now available from Littelfuse, Inc. is the AF0100, a compact, cost-effective arc-flash protection relay sized to fit tight footprints and budgets.

Now available from Littelfuse, Inc. is the AF0100, a compact, cost-effective arc-flash protection relay sized to fit tight footprints and budgets. The Littelfuse AF0100 is the third in a series of arc-flash relays and is 30 percent smaller than previous models. Measuring just 90 mm (3.5 inches) high x 128 mm (5.0 inches) wide x 60 mm (2.4 inches) deep and both DIN-rail and surface-mountable, the AF0100 can be retrofitted easily into existing switchgear or pre-installed in new equipment with little or no configuration.

The AF0100 relay detects light from an impending arc-flash and rapidly trips to reduce potential damage. Its two light sensor inputs accept point sensors and fiber optic sensors in any combination for installation flexibility. What’s more, it provides plants with a cost-effective, energy-reducing arc-flash mitigation system to help comply with the latest National Electrical Code (NEC) requirements.

Exclusive to Littelfuse arc-flash relays, the design includes two internal trip paths for greater reliability. If the first trip path fails, the backup trip path seamlessly takes over and sends an alarm notifying the operator. The backup trip path also initializes quickly upon power up to ensure protection while the system is energizing and when arc-flash risks are higher. Additionally, sensor health is continuously monitored to ensure failsafe operation.

The relay also meets the unique needs of generator equipment manufacturers that need arc-flash protection in a small package that also matches the demanding reliability requirements of their equipment. Two essential requirements involve transportation and temperature because generators travel distances to their destination and are used outdoors where they are exposed to extreme temperatures. The AF0100 was designed to withstand extreme vibration and temperatures ranging from -40°C to 70°C (-40°F to 158°F). In addition, two isolated Form-C contacts are provided for generator applications where multiple devices need to be tripped in an arc-flash event.