Converting an RP06 from Three-Phase to 220VAC Single-Phase

These modifications are completely reversable!

RP06 disk drives are normally powered from a 208 VAC three-phase delta circuit in North America, or Wye for European use. The power cord on the drive connects to all three phases but the drive only uses phase A and phase B. You can daisy-chain the power on two RP06 drives and the second drive uses phase C.

Three-phase power is unusual in a USA residence so the drive must be modified in order to run it in a home. There is a Phase Jumper installed into the left side of the Power Distribution Unit that selects between Delta and Wye power sources. You can modify this phase jumper and the wall outlet wiring so you don't need to modify any of the wiring inside the drive.

The drive normally uses the Delta plug so I modified the Wye plug. This will let me easily put the drive back to original condition. I moved some of the original wires and soldered three wires together. The final version of the plug has pins 1 & 2 connected together and pins 5 & 7 & 8 connected together.

Note: I could have connected 4 & 5 & 7 & 8 together and only fed power through the Phase A and Phase B wires. I was a little concerned about the amount of power that the spindle motor draws so I fed the spindle motor through the Phase C power wire.

I used a three phase AC outlet so I didn't need to modify the power cord on the RP06. In the power outlet I connected Phase A & C to one side of the 220 VAC circuit, Phase B to the other side of the 220 VAC circuit, and connected the ground. I did not connect the neutral on the outlet.

Click on the diagram below to see a larger version.

This modification worked for me. Let me know know about improvements, suggestions, and comments to this procedure.