Features: * It can be operated anywhere, and no distance limit. * Up to 200 authorized phone numbers. The 1st ~3rd user numbers can receive SMS, and the 4th ~6th user numbers can receive calls when alarm occurs. 1~200 authorized phone numbers can call T201 to turn on/off the Relay0. * External AC/DC power status monitoring, AC/DC power on/off will send SMS and immediately call 6 preset mobile phones. * Timer report can be set every few hours, and its status/value will be automatically sent to 6 preset mobile phones immediately. * Support remote reading of historical data via SMS. * Automation system, when the temperature, power supply alarm or normal, it can link to Realy1 for operation. * Alarm output, when alarm occurs, it will output for 30 seconds. * Internal rechargeable battery can be used continuously for 6 hours. * Safe, use caller ID and password for identification, unknown callers will be ignored. * It can be programmed via SMS commands with password protection. * Based on GSM web, suitable for many applications. (Temperature, power status, solar panels, DC voltage). Tips: 1. Please read the user manual carefully before installing and setting up the control unit. 2. Install the system in a hidden place. 3. Avoid pouring water into the control unit. 4. Ensure that the connection to the main power supply is secure. Specifications: Product name: Monitoring Relay Rated voltage: DC 9V~24V / 1A Working temperature: -10℃~+60℃ Storage temperature: -20℃~+60℃ Relative humidity: 10-90%, no condensation Working frequency: GSM: 850/900/1800/1900MHz 3G WCDMA: 900/2100 MHz UMTS 3G CDMA2000: 850/1900MHz UMTS 3G: 850/2100MHz UMTS Communication protocol: GSM PHASE 2/2 + (including data service) Relative voltage of output relay: 3A / 240V AC SIM card: Nano type, 3V Antenna: 50Ω SMA Wired switch: support Temperature sensor: Temperature: -55℃~+125℃:0.1℃ Alarm output: output voltage = DC input voltage, current: