221-2/3 High Temperature


221-2/3 High Temperature

121-2s Spark Detector

The 221-2 and 221-3 are similar to the 121-2 and 121-3 but are designed to interface with fire alarm control panels, PLC's, etc.

The 221 requires 24 VDC and provides an open collector control for powering various devices.

The 221 offers a standard 4 wire interface with normally open, dry contacts.
The 221-2 has two fiber optic probes and the 221-3 has three.


Response less than 1 millisecond

Sensitivity less than 100 nano watts

Broad Spectral Response

Wide field of view (70º per probe)

Easy mounting

Smooth surface to help self clean

Two or three probe versions

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221-2/3 High Temperature