The PSR-1 is a Light Sensitive Resistor that may be used as an input to indicate the presence of light at the sensor location. The PSR-1-T is a PSR-1 coupled with a B420-P transmitter.

The PSR-1-T produces a 4 - 20mA output signal. The sensor is designed to be mounted in the end of a weatherproof conduit box.

The PSR-1 has a resistance in darkness in excess of 1 Mohm and resistance in bright light of less than 1.5 k ohm.The PSR-1and PSR-1-T indicate the presence of absence of light.

They should not be used for foot-candle control of occupied spaces. The PSR-1-T is calibrated for 4mA in bright light > 100 foot candles and 20mA in darkness < 0.1 foot-candles.

PSR-1
Output (non-linear)	>1 M ohm in dark <1.5 k ohm in bright light
Temperature	-25｡紊 - 75｡紊 (-13｡紮 - 167｡紮)
PSR-1-T
Power	12 - 35 VDC
Max current draw	22mA
Output (linear)	4 - 20mA(current limited to 22mA)
Temperature	-25｡紊 - 75｡紊 (-13｡紮 - 167｡紮)