The ACI DRN3.1 Series Electronic Transducer is an interface that allows microprocessor control of a variable resistance. The DRN3.1 has on-board fail-back relays that lock out the original resistive signal during DRN3.1 operation. An easy local override can be made by placing a fixed (or variable) resistor between W and R Fail-safe terminals. There are LED indicators for power and input signals. The DRN3.1 accepts an ANALOG, PULSE, or FLOATING POINT input signal (including triac) and converts it into a proportional resistive output. The output resistance does not wrap around if the input signal exceeds the highest or lowest selected input value.