Visually monitor signal calls from the furnace/air handler circuit boards
Interrupt those signals and send the motor any signals you desire, to observe motor operation
Get a visual display of motor RPM and the calculated CFM (on most systems)
Get a visual readout of all 4 system taps
Get a direct readout of the control voltage in the motor (low voltage here causes erratic operation)
If a problem is traced to the motor, one switch press starts an automatic analysis to clearly indicate if the problem is in the motor's electronics, or one of seven possible winding problems
Microprocessor controlled, but easy-to-use, only 4 switches
Rugged case with carry handle and lead storage compartment