G540 powersupply question.

[Alekoy]

Hi.
just about ready to fire up my CNC6040 Chinese mill that I bought on Ebay, after reading other users experience with it, I decided to buy it without the control box and the VFD.

So instead I'm using a Danfoss VFD I already had, and a G540 driver.

the steppers on the mill is rated at 3A each, so I soldered some 3K resistors in on plugs.
The question I have is, what PSU should I get.
since each motor is 3A, and I plan on adding the 4th axis a little bit later, I guess I need at least a 12A supply, looking at probably 15A.

The next thing that has me confused is the voltage.
I measured each of the coils in each of the motors to be a little bit under 2mH, 1.9mH to be exact, I know the manual says that you should take 32 and multiply it with the root of the mH.
what it does NOT say is if it is the mH of one coils, or the mH of both coils in parallel or series...

And while we are at it, should the supply voltage be set exactly at the calculated voltage?

[ger21]

The maximum the motors will draw is 2/3 the rated current of each motor, so you really don't need more than 8 amps.

If it's a 4 wire motor, then one coil. If it's an 8 wire motor, then measure it as it would be attached to the drive, either series or parallel.

A 48V supply would work, but the motors may run a bit warmer. Maximum speed is proportional to voltage, so as you decrease voltage, your potential maximum speed will decrease.
How the machine is geared and driven may have an effect on this as well. If you're not using the maximum available speed of the steppers, then you may not see any difference from a lower voltage, other than cooler motors.

[Alekoy]

Thanks, 48V supply ordered.