The GRD-4GM series data loggers are designed for remotely monitoring sensors and other instruments with cellular & satellite connection to a remote server for data logging and control. GRD units are available with 0-10V, 4-20mA, digital state and pulse inputs, and digital outputs as well as serial ports for Modbus Master/Slave communications and connection of a satellite modem. Data is sent from the units to a remote server, where the Middleware software creates a MySQL ...