Notifier by Honeywell NFXI-TDIFF Addressable Heat Detector + B501AP Base

The Notifier by Honeywell NFXI-TDIFF combined with the B501AP addressable mounting base is an advanced analogue-addressable thermovelocimetric heat detector engineered for commercial, industrial, and institutional fire safety installations. Equipped with low-mass thermistors and microprocessor-controlled evaluation, the unit detects rapid temperature increases exceeding 10°C/minute as well as a fixed 58°C thermal threshold (Class A1R). Designed for environments where smoke, dust, or steam make optical detectors impractical, it operates over a 15V to 28.5V DC range on the Notifier Opal digital protocol. The detector features integrated short-circuit loop isolation, two 360-degree tri-color LEDs, rotary decade switches for quick address configuration (01–159), and EN 54-5 and EN 54-17 certifications.