Control System Testing: Fucking Machine

Procedure to check the motor control system using a multimeter. Start with the machine unplugged.

1 – Open the hand control’s box, four Phillips screws. Confirm every wire end in there is firmly connected to something.

2 – Check the switch with a multimeter. Set for a 200 ohm resistance. With switch ON, confirm that the two terminals to which wires are connected read near 0.

3 – Reassemble the hand control box if these tests are passed.

4 – Remove the control cover from the Probe-style head (4 Phillips screws) or remove the control box cover from all other machines (4 screws, head may vary). Confirm that everything is connected… three wires from the hand control to the three-position terminal strip on the side, four blade connections across the end of the control.

5 – Set multimeter for 20K ohm resistance. Hand control switch ON, knob to about 5. On the terminal strip, locate little letters at the base of each terminal, H W L. Read for the following:

H / L ~5K
H / W ~2.5K
W / L ~2.5K

6 – If everything has checked out so far, check output power carefully so as not to get shocked. Turn hand control OFF. Plug in machine. Turn hand control ON, knob to about 3. Set multimeter to 200 volts DC. Measure for DC voltage across the terminals where the motor is connected: A(+) and A(-).

7 – Reassembly control cover.