Kalimero
Any wires that are not being used should be individually insulated and secured against accidental contact.

Kalimero,

Those extra wires were intended for other functions that have not been completely worked out yet.

Kalimero,

As Heath wrote, you need to individually tape the ends of each unused wire (or use a wire nut on each unused wire) to keep them from shorting together.

An eight lead motor can be used in Half-Coil mode when you don't have adequate Amps available from the power supply, otherwise, I would suggest that you use all eight leads to take full advantage of the motor. The wiring diagram that Gerald posted at the top of this thread shows the correct method to use to connect an eight wire motor.

Thanks..

6 wire half coil?
 

I have the PK296A2A SG7.2 with 58 Volt PS
6 wire

With a 6-wire motor you can wire them either:
- UNIpolar (use half the motor), or
- BIpolar series (UNIvoltage X 1.4 and UNIcurrent ÷ 1.4) ?
(only 4 wires will be connected - 2 wires will not be connected)

diagram C Using Trem #3 Black ,Trem #4 green , Trem #5 red and Trem #6 blue. As shown in
The wires which are not connected, are separately(individually) insulated.
Hooked a motor this way and get a green light on the 203v. green lights on J1 PMDX 122 motor will not move. Has holding torque

#20 Mike uses-
For half-coil connections with a Gecko G202 or G203, I use the Black wire and the Yellow wire for the A coil and the Red wire and the White wire for the B coil. i.e. Term #3 = Black wire, Term #4 = Yellow wire, Term #5 = Red wire, and Term #6 = White wire.
Hooked a motor this way and get a green light on the 203v and green lights on J1 Pmdx 122 motor will not move. Has no holding torque.

In diagram B what do you mean center taps?

I have the same setup with 58v, Geckos, OMs. Here is my setup:

Gecko = Motor
A- = Green
A = Black
B- = Red
B = Blue

White and Yellow are not connected.

Geckos all have 33K resistors (Orange/Orange/Orange).

Everything on mine works fine.

A good solution here is to just trim off the two extra wires at slightly different lengths, then shrink wrap the entire bundle of wires.

Ill check the resistors tomorrow.
Thanks

Be sure to jumper the PMDX-122 correctly for the G203v. You MUST connect terminal #10 on the G203v (Common) to Ground on the PMDX-122. The PMDX-122 must pull the step and the direction signals High when it sends step pulses to the motor.

(My PMDX-122 came jumpered from the factory ready for use with the G201 and the G202 stepper drivers, not for the G203V stepper driver. JP1 is the jumper to check.) Rest of PMDX discussion moved to:
http://www.mechmate.com/forums/showthread.php?t=346

When wired half-coil (Black/Yellow, Red/White), the maximum voltage for the PK296A2A-SGxx motor is about 38V. If you're using a 58V power supply, you will need to wire the motors using the Black/Green, Red/Blue wires, otherwise the motors will get too hot.

I'm looking over the manual here, and wiring the 7.2 geared OM's bipolar from the Oriental Motor site and I'm seeing-

A- = Green
A = Black
B- = Blue
B = red

I swapped the red and blue on the coils. Does this just change the direction? So on the X axis one motor will have swapped wires?

Same holding torque but different number of leads...
 

hi,

Suppose we have 2 motors with the same specs, but one has 6 wires and the other has 8.

Would there be a difference in torque between the two motors when running them half-coil? Will both of them theorically have exacltly 1.4x less holding torque than if they were to be wired "full coils"?

thanks,
francis

Theoretically speaking, yes, as long as the construction of the coils are the same.
Again, 1.4X is only an approximate/general number, there are many other factors involve too, i.e. the corner frequency, the coil internal resistance... etc etc... Just to confuse you further :p

thanks ken,

I have another question,

I have only a 56VDC power supply. Can I alter the amperage feed to the motor instead of the voltage to find a "perfect balance" between performance and overheating?

Richards posted earlier on this thread that he runs his PK299-F4.5a at 35VDC and 6.3 amps, bipolar paralell, and the motor runs much smoother than at 60VDC, as he first tested.
Could I run the same motor at 60VDC, for example, and lower the amperage instead of the voltage, and get a better balance, just like Richard got, using 35VDC?

Thanks again,
F

Francis-

Mike (Richards) and others are actively discussing that sort of question starting around post #40 here.

Francis,
I'll leave a post in the other thread that Brad highlighted to respond to your question.

Francis, a very common misconception is that the published holding torque of a motor is the important criteria for a router.

The important torque is the one at higher speeds, when the machine is cutting.

Fransic, like all other electrical machine, you cannot just alter the current of the motor, electric motors draw current when they need it even if it means self-destruction & the only thing we can do is to LIMIT the max supply current, just like restricting the fuel line of an engine. AND it is almost impossible to have a "perfect balance" all the time, due to the vast variate operating condition of stepper motors in an CNC machine (speed change, accelerare, decelerate....etc etc). You can only work within a safe operating "ZONE" at best.

To confuse you even further, the other factor which contributes to load current are voltage, frequency, coil inductance, coil internal resistance, coil capacitance, magnetic flux of the magnet & external loads such as friction... etc etc etc... not all necessary to know to operate a motor properly...

Thank all,

It's really worth it having a look here (same link bradm showed me) on the posts about motors electrical characteristics and playing with what you have to keep the heat down and have enough power available...
f.