... RTU).It has multiple functions (analog input,relay output, digital input, digital output, pulse ... automation, telemetry, finance, POS, water supply, environment protection, post, weather, and so on.Product Feature ... extended protocol.When reporting acquisition data failure, acquisition data are saved to 2M ... 900/1800/1900MHz(optional)Compliant to GSM phase 2/2+GPRS class 10, class ...