[Mariss Freimanis]

"I took it as "Not Connected", but wanted to be absolutely sure"

I'm glad you checked and verified. I run into this all the time when it comes to IC pin designations. I err on the side of caution and assume the prohibitive meaning unless the datasheet expressly indicates the "pin not connected" definition. The error in writing a manual is in assuming a familiar convention translates elsewhere and carry the same interpretation.

Your original question was regards to "parking" unused unipolar (6-wire) motor wires; please leave them unterminated and insulated at the motor end. While I'm at it, I'd like to just mention a few other things may have already taken care off:

1) If you run a 6-wire motor in the 'half-winding' mode, set the current to the motor's rated current. If you run the motor in 'full-winding' mode, set the current to 1/2 the motor's rating.

2) Use 18-gage wire for the motor cable. Any wire-gage substantially less than that will cause the cable to overheat. Do not use manufactured connector and cable sets marked 'serial port cables'. They are intended for milli-amp loads like mice and use 28 gage wire.

3) Use the mating DB-9 connectors we supply with the G540. DB-9s come in 1 Amp and 5 Amp per pin flavors and you can't tell the difference by looking at them. The 1 Amp ones will overheat (3.5A being pushed thru a 1A pin) and damage the mating G540 DB-9 connectors.

4) Place the current set resistor on the G540 end DB-9 cable connector. Putting it at the motor end results in noisy motors because the motor wires in the cable inject noise into the current set connections.

5) Do not use a power 'On/Off' switch the DC side from your power supply. Put the 'On/Off' power switch on the AC side going into your power supply.

6) Have the power supply near (1ft or 300mm) the G540. If it must be further away, Place a 2,200uF to 4,700uF capacitor rated at 63VDC across the G540 power input terminals. Mind the capacitor's +/- voltage polarity.

[Devastator]

2) Use 18-gage wire for the motor cable. Any wire-gage substantially less than that will cause the cable to overheat.

That got my attention for sure. I've been using 20 gauge for the past two years to run 3A motors. In addition, a couple of the cables are 12 feet long. Haven't noticed any cable heating even on cut files of 12 hours or more. That doesn't mean it is not happening, I just haven't noticed it. I'll shop around for new cable.

Thanks for the info on the DB-9's, I had no idea there were different versions. Where is the best place to order extras?