MRI-5251B Low Profile Intelligent Thermal Sensor, FT 135F

Model MRI-5251B uses an innovative thermistor sensing circuit to produce 135°F fixed temperature detection in a low profile package.


These thermal detectors provide cost effective, intelligent property protection in a variety of applications.

Plug in. Requires a Low Profile 200 Series Base.


  • Sleek, low profile design
  • Detectors are equipped with a built-in analog communications module
  • Smoke detectors are available with photoelectric or ionization technology
  • Photoelectric detectors are available with additional fixed temperature detection
  • Heat detectors are available as fixed temperature or fixed temperature with rate-of-rise detection
  • Dual LEDs indicate communications and activate steady when in alarm
  • Low profile base provides easy interchangeability
  • Low standby current
  • Rotary address switches
  • Magnetic test feature
  • Superior EMI protection
  • Sealed against dirt, insects, and back pressure

Product Documents