The SERIES 509 was developed specially for use with microprocessor-based systems. The conductors are insulated with color coded FEP. They are then twisted with a copper drain wire. An aluminized polyester tape is wrapped around the conductors and drain wire and then FEP is applied. The finished construction can withstand temperatures in excess of 400°F (204°C). Twisted conductors minimize electromagnetic interference (EMI) and the shield tape eliminates most problems associated with AC “noise” in the sensing circuit.