Hi everyone.
I'm a new member, just bought TB6560 Driver and 3 Nema 17 steppers on e-bay for my first CNC.
Construction is nearly done, but I wanted to test the electronic.
I connected the driver to PC and started Mach3 mill.
I've configured it like the manual says (the one I got with the driver)
I've loaded roadrunner.tap G-code and started it.
The motors started turning, and everything looked fine.
I took about 6 minutes to complete.
But there's a problem.  The motors heat up really bad.
They are cold when they work, but when they stop they get hot pretty quickly.
In those 6 minutes they were cold, but when the program ended they heated up
in like 5 minutes so hot I couldn't touch them for more than half a second.
I use 24V 10A power supply but I've set voltage to 9V (checked with multimeter)
On the motors it says 11V
Motors are 17PM-K301-11V
They have 6 leads but I've connected 4 (4 connectors on the board for each axes)
I've connected leads like this

1 - A+
2 -
3 - A-
4 - B+
5 -
6 - B-

So 2 and 5 are not connected to anything.
All leads are colored gray, but I've checked short circuit with multimeter on A+ and A-
then B+ and B- to be sure they are of the same coil and they are.

How can I fix this?
I don't think a machine should work with motors so heated up.

Oh and one more thing.
I've just clicked "REF ALL HOME" in mach3 and Z axis motor started turning, others were still but had a good hold torque. I left it to turn for a few minutes and it remained completely cool but other two started getting warmer. While it was turning I've checked voltages between A+ and A- then B+ and B- on each motor.
Those two that weren't turning had 8V between A+ and A- and 8V between B+ and B-, but Z axis motor that was turning showed 0V on all.

I've set current setting on 25% (lowest) and decay mode on SLOW on the driver dip setting board
Micro step setting is 1

Did you purchase the "optional" step current board so you could reduce the current.
Post you manuals for the driver and board.

RICH

No.
There are dip switches on the controller board that are used to regulate current.

Current may still be to high for the motors even at 25%. They are realy small steppers.
RICH

THX Rich.
You were right. The current is too high.
But I bought 2 stronger motors (1.2 Nm) with higher current rating and now it seem that the smaller motor isn't heating up anymore, nether are 2 new motors.
Problem solved.