FW521 Heat Detector

The FW521 is an intelligent heat detector with both fixed-temperature alarm at 135°F (57°C) and rate-of-rise alarm characteristics at 15°F/min (8.3°C/min), UL/ULC listed according to UL 521 and ULC-S530 for fire protective signaling systems and indoor use, plus FM approved. It features a slim design combining visual appeal with high reliability standards.

The detector incorporates a microcontroller unit (MCU) that performs comprehensive self-diagnostic tests and result analysis, ensuring consistent performance in heat detection applications. Operating on 24 VDC nominal voltage (17.6-28 VDC range) with minimal current draw of 0.1mA standby and 1mA alarm, the FW521 provides dual detection methods for enhanced fire safety.

The intelligent, addressable detector takes one address on the signaling line circuit (SLC) of the fire alarm control panel and can be wired in Class A or Class B configurations. Suitable for ceiling-only mounting with 50-foot spacing, the detector operates reliably in temperatures from 32°F to 100°F and humidity from 0% to 93% RH, making it ideal for areas where smoke detectors may not be suitable due to ambient conditions.