WHY-PH1 For your safety, please read manual instruction carefully before beginning installation Please ensure the power being turned off before connecting wires! Technical Specifications Power supply: 12-24 VAC/DC or 1.5 v LR6 AA Power absorbtion: TX ≤8 mA RX ≤40 mAWavelenght: 940 nm Nominal range: 20 m Working temperature: -20º/+60°C Relay contact: max 500 mA and 48 VAC/DC Size: 127 x 50 x 35 mm