How to use it?
<br />1.Install each pair at the opposite positions.Then there is a infrared area between these two detector parts. When someone passes the infrared region, the detector will send alarm signal to the security alarm host (which not included here).
<br />2. Install Distance(Max.)in the above chart means the maximum install distance between the two detector parts.
<br />3. Great to be installed for security system in school, office building, hosipital, home yard, etc.
<br />4. Detecting range can be reduced to 30% in bad weather conditions, like rain, dust, etc
<br />5. English Usage Manual included in the pack. It will give you detailed instructions.
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<br />Technical Parameters
<br />Detecting Range: Within 15m
<br />Work Voltage: DC/AC 12-24V
<br />Relay Output : N.C/N.O.
<br />Wave Length : 940nm
<br />Operating Temperature : -25 ~  +55
<br />Dimension : 49.2 x 75 x 29.6mm
<br />Water Proof, UV proof
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<br />Package include:
<br />1 x Infrared sensor (transmitter & receiver)
<br />Some Mounting screws