20mA sensor transmitters allows industry standard temperature sensors to be directly connected to PLC 20mA inputs and industrial IO modules. The 20mA sensor transmitters connection is a standard format in industrial measurement and control systems. The 20mA signal allows the temperature sensor measurement to be run much further than the direct connection of the temperature sensor itself. 20mA signals can be run directly for thousands of feet, when using the correct cable and power supply. Many PLC inputs either standardly or optionally can be configured for 20mA, and it is not unusual to find spare inputs in an installation.