The ACI High Temperature Immersion Series sensors and transmitters are a single point immersion sensor featuring a three wire RTD sensor assembly using Nickel Fiberglass Lead wires, a 316 Series stainless steel probe, and a Machined 304 SS Steel thermowell. The “INW” version of the product can be ordered without the thermowell for applications in which there is an existing thermowell, increased design parameters or other materials are required for higher corrosion resistance. The three wire sensors can be used with a two-wire transmitter by connecting the two (Red) colored wires to one of the RTD Terminal blocks with the 3rd wire (White) wire going to the second RTD Terminal block. The purpose of the 3rd wire is to compensate for external lead wire resistance that will affect the accuracy of your sensor output when using with a three-wire temperature transmitter or sensor configuration on your Building Management System or PLC (Programmable Logic Controller. ACI recommends the use of 18 AWG lead wires to reduce the external lead wire resistance when using a Platinum RTD. The operating specifications are for both the sensor and transmitter as designated in the specification table. Standard enclosure options include the “-GD” Galvanized or “-BB” Aluminum weather proof enclosure. NIST Certificates are available for all of the configurations listed in the ordering grid on the back of the product data sheet. For best accuracy, ACI recommends the use of the TTM100 or TTM1K Series Matched transmitters with a 3 or 5 Point NIST Calibration Certificate since they include a second calibration step in which the RTD and transmitter are calibrated together as a system, which removes most of the sensor error over the calibrated temperature span of the transmitter. Applications: Burners, Boilers, Stacks, Exhaust, Incinerators, Ovens, Plastics Processing, Process Heating, Process Control, Steam Lines