The load applied to the DUT is equal to the total equivalent series resistance between the positive terminal of the apparatus and GND in addition to the resistance of the leads connecting the DUT to the apparatus. The resistors on the resistive track all connect to each other in series, forming an open loop where there is no direct connection between the first and last resistors. The stepper motor moves a mechanical arm assembly that connects one node of this resistive track to GND and acts similarly to a wiper on a rheostat. This mechanical arm contacts the resistive track via high-current pogo pins. The mechanical arm assembly is connected to the rotor of the stepper motor, and is fixed in place using a set-screw. Between the connection point from the resistive track and the rotor, the mechanical arm makes another connection to an elevated copper base plate via additional pogo pins as shown in Figure 3-5. By using the mechanical arm to set the load, one end of the resistive track can be used as a load, while the other end can be used to apply positional feedback. The mechanical arm assembly allows the input terminals of the resistive load to remain stationary and eliminates the need for a slip ring.