Littelfuse Launches Its Most Compact Arc-Flash Relay for Tight Spaces

News Beat
News Beat

CHICAGO, September 27, 2023 — Littelfuse, Inc., (NASDAQ: LFUS), a diversified, industrial technology manufacturing company empowering a sustainable, connected, and safer world launches its AF0025 series, a cost-effective arc-flash protection solution in our most compact package for OEM applications. The arc-flash relay significantly reduces arc-fault damage in ac and dc compartments by detecting the light from an arc-flash and rapidly providing a trip signal. With a depth of only 1.82” (46.23 mm), the compact design can be surface or DIN-rail mounted in the smallest places. This makes it ideal for renewable energy applications such as combiner boxes and inverters, industrial applications including uninterruptible power supplies (UPS) and variable frequency drives (VFDs), as well as junction boxes and panels where space is limited.

The use of one or two sensors makes the AF0025 series suitable for small or medium-size panels, with onboard or remote reset capability. Since no settings or computer are needed for setup, this arc-flash relay is quick and easy to install.

“The damage caused by an arc-flash event can be costly both to personnel and equipment. And, depending on the power of the arc-flash, it can take months to repair,” stated Richard Dale, Product Manager, Littelfuse Industrial Business Unit. “The compact AF0025 arc-flash relay detects the problem within five milliseconds and sends a signal to cut the power to reduce or even eliminate the risk to personnel and equipment–saving lives, expensive repairs and decreasing downtime.”

Additional AF0025 arc-flash relay features include:

  • Fixed light sensitivity which does not require adjustments during installation
  • Internal fail-safe design providing redundant solid-state circuitry
  • Selectable fail-safe and non-fail-safe operation so trip output can be configured to work with shunt-trip or undervoltage-trip devices for added flexibility
  • Error output confirmation to indicate if arc-flash is experiencing an error or is actively providing protection
  • Conformal coating to protect product from harmful environmental conditions

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Littelfuse (NASDAQ: LFUS) is a diversified, industrial technology manufacturing company empowering a sustainable, connected, and safer world. Across more than 20 countries, and with approximately 18,000 global associates, we partner with customers to design and deliver innovative, reliable solutions. Serving over 100,000 end customers, our products are found in a variety of industrial, transportation and electronics end markets — everywhere, every day. Learn more at