I bought a 6560 board and motors getting burning hot

I bought this board, a 6560 3 Axis board.
I put 12 volt supply and tested it with only 1 nema17 motor on the X axis.

the jumpers on the board are set to the lowest current, 20%, which say its for giving out 25% of current, which shuold be about 1.5A per motor,suitable for nema17 motors. The range of current being 1.3 to 3Amps.

I left the motor connected. In about 5 minutes, I could not touch the motor without getting scalded. A little more and perhaps I was about to see smoke.

Immediately i disconnected all power and put the motor on a cool metal object to take out as much heat as possible, hoping i did not do any damage to my motor.

Can someone tell me why my motor got so hot, nearing burning temperatures?

Also has anyone used Mach3 to control this board and what settings they are using or recommend?

Thanks

depending on which manufactures data sheet you look at
stepper motors run at 70 to 80 centigrade !! too hot to touch for long

this is why many stepper drivers reduce the motor current when the axis is idle

Do you have the specifications for your motors ?

Usually you should have the motor current , the coil resistance , inductance and voltage
(the voltage is the DC voltage to get the rated current to flow through the coil)

ideally the inductance should be about 2 to 3 mH , to work when using a 24V to 34V supply for the TB6560 board
the 36V power supply found in some kits is over the maximum voltage for the TB6560

Attachment 386660

To achieve a reasonable motor speed
the TB6560 supply voltage will be several times the motors rated voltage , the current being limited by the stepper driver
the supply voltage required is related the motors inductance

the higher the inductance, the higher the stepper drivers supply voltage will be required to force the current through the coils as motor speed is increased


john