System Sensor 5151 is a combination fixed and rate-of-rise, plug-in heat detector.​​

The 5151 thermal detector meets the needs for applications where rapid response is vital and rapid temperature increases would only be caused by a fire emergency.

The detector initiates an alarm in response to both rapid rate-of-rise conditions (increases in excess of 15°F per minute) and fixed heat (135°F). This enables the heat detector to communicate an alarm to the central control panel prior to reaching its fixed set point for high rates of rise, providing a timely response to both rapid and slow temperature increases.

A full line of accessories are available for this product.

Features
• Low standby current
• Compatible with 400 Series product
• Two visible LEDs “blink” in standby and provide a 360° field viewing angle
• Detector head plugs easily into base
• Built-in test switch
• Wide variety of mounting bases with built-in shorting spring