The SM-420 adaptor has been designed to interface from any 4 to 20 milliamp tank sender unit to the Smart Switch Technologies HT-100 or HT-100/P Tank Control System.
Wiring Diagram:
Calibration:
The tank calibration is preformed inside the HT-100 or HT-100/P therefore before starting ADJUST the tank sensor probe for the FULL 4 to 20 milliamp current swing. Calibration can now be done as per the manual for the TC-8000 or TM-4000 unit.