The Vehicle Loop Detector is mainly used to detect the existence and passing of vehicles;Reset Switch: The reset switch enables the detector to be manually reset during commissioning and testing. This results in the detector re-tuning the sensing loop and becoming for vehicle detection Selectable Time: This feature sets the length of time the relay will be energized for 1 Second or 0.5 Seconds; Relay : The Relay may be configured to energize on detection of a vehicle or when the vehicle leaves the loop Sensitivity Boost : This feature sets the undetected level to maximum sensitivity and is used to prevent loss of detection of high-bed vehicles Switch Selectable Sensibility: 4 sensitivity setting are available on the switches to allow flexibility in configuration;Switch Selectable Frequency: 4 frequency settings are available to prevent -talk between adjacent loops Filter Option: This option is used to a delay between detection of the vehicle and switching of the output relay . This relay is normally used to prevent detection of small or fast moving objects;Permanent Presence Option : This feature detection of the vehicle will be maintained when the vehicle is parked over the loop for extended periods. Specifications: Supply voltage:220V AC :4.5VA Output relays:240V/5A Operating temperature:-20~65 Celsius temperature:-40~85 Celsius Frequency range:20 kHz to 170 kHz Temperature compensation:50 Celsius/ h Reaction time:10ms Signal holding time:Unlimited/limited Sensitivity:Higher:0.02%/high:0.05%/low:0.1%/lower:0.5% Loop inductance: loop plus connection wiring: 50H to 1000H. perfect is 100H to 300H Loop connection wiring:200 meters long. The resistance is less than 80hm, twisted at least20 per meter Relative humidity:Less than 90%No condensation Weight:283g Colour:black Material:Plastic + metal Package Contents: 1 x Vehicle Loop Detector Only the above package content, other products are not included. Note: Light and different displays may the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.