Littelfuse Blog

Littelfuse Makes Electrical Safety Accessible and Affordable with New AF0100 Arc-Flash Relay

Littelfuse 3/2/2017

AF0100 Arc-Flash RelayNow available from Littelfuse, Inc., the global leader in circuit protection, 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 new AF0100 meets a real need in the marketplace to address budget and space constraints,” said Dean Katsiris, product manager, Industrial Business Unit at Littelfuse. “The AF0100 overcomes both challenges by delivering industry-leading arc-flash technology at a fraction of the cost and space required by traditional relays.”

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.

“Generators produce a lot of energy that can directly feed an arc flash and self-destruct not only the generator, but the mission-critical application relying upon it for power,” continued Katsiris. “One customer estimated they could outfit their entire fleet with the AF0100 and get a full return on their investment in about a year, plus save money versus doing nothing. This means a safer and more reliable generator for them and for their customers, and at a net cost savings.”