The most common use of the SEM1010 is to provide isolation between a field mounted, two wire, (4 to 20) mA transmitter and a PLC type device with a common power supply.

The two wire transmitter connected to the input terminals of the SEM1010 does not require a power supply. The supply required to drive the transmitter is obtained from the power supply connected to the output terminals.

Total isolation is maintained between the power supply on the output and the two wire transmitter.