Siemens (Pyro) | HI921

Siemens HI921 Intelligent Addressable Thermal (Heat) Detector

The Siemens HI921 is an intelligent, addressable thermal (heat) detector designed to provide advanced fire detection through precise temperature monitoring. Incorporating state-of-the-art thermistor technology and microprocessor-based signal processing, the HI921 ensures high reliability and accuracy in various environments. 

Key Features:

• Field-Selectable Temperature Settings: Offers seven pre-programmed temperature settings ranging from 135°F (57°C) to 174°F (79°C), including both fixed and rate-of-rise options, allowing customization to specific application requirements. 

• Low-Temperature Warning: Capable of providing a warning signal at 40°F (4.4°C), aiding in the prevention of water freezing in sprinkler systems, in compliance with NFPA 72 standards. 

• Tri-Color LED Indicator: Equipped with a 360° viewable LED that flashes green for normal operation, yellow for trouble conditions, and red for alarm states, facilitating easy status monitoring.

• Built-in ISOtechnology: Features integrated isolation technology to enhance system reliability by isolating short circuits on the signaling line circuit (SLC), supporting True Class-X SLC operation. 

• Polarity-Insensitive Wiring: Supports polarity-insensitive wiring configurations, simplifying installation and reducing potential wiring errors.