the connection board is likely failing to bridge the communication gap

The Reznor 10120 Blower Shaft is a precision-engineered 1-inch diameter replacement shaft measuring 39

or Hytrel sleeves

you will see an open circuit (infinite resistance)

Nidec-US Motors LX7930 Motor R-407C the connection board is likelyThe Nidec US Motors LX7930 is a heavy duty direct drive blower motor engineered for commercial and industrial HVACR applications requiring a 460V single phase power supply. Rated at 3 4 HP with a synchronous speed of 1075 RPM, this 3 speed motor allows for precise airflow modulation to match system static pressure and load requirements. Built on a 48Y NEMA frame, it features an Open Air Over (OAO) enclosure designed for continuous duty in the blower's