Bench testing here again . Appyling your shop power of 120 (?) volts to the Orange wire is fine. Connect the Orange wire in the same steps as before, disconnect the Orange and the Black/Red from the transformer and connect the Orange wire to the Black/white #4 pinout wire of the transformer . Check at the output for 115 volts at # 10 & 11 which is the isolated supply for the monitor. What is your shop voltage? There is mention of an output of 18.5 volts rather then 21 volts at pinouts # 6&7. The ouput on the secondary will be affected by the input on the primary. If your input is less then 110 volts the secondary will be lower than rated. Pin outs #3 & 5 are the neutral input connections for the transformer. Pinout #4 is the Hot wire input to the transformer. Your shop 120 volt wiring is Black = Hot and White = Neutral.