TB6560 Blue dummy "load" to prevent damage.

Hello,

I have one of those 3 axis blue TB6560 ebay jobbies that I would like to run with only one motor. It's my understanding that you shouldn't power it on without a motor(s) attached or it will damage the driver. As I am an electronics newb, what can be done to prevent this so I don't have the unused motors hanging off it unnecessarily? I won't using those 2 axis at all so I don't believe it needs to be an actual "load". I'd like to keep the driver fully operational for potential future use.

Thanks
Dan

While I know that you don't know electronics, you really, REALLY, REALLY, should to mess around with these cheap hobby drivers.

You DO NOT need a dummy load. That said, DO always follow the instructions and NEVER, EVER unplug or change motor wiring while the driver has ANY power applied. The sudden change likely will blow it sky high.

The logic and reasoning is that modern stepper drivers are chopping current drivers. What that means to you is that you should be using motors "rated" at a low voltage (generally indicates a low inductance and low resistance coil) VS a higher power supply voltage feeding the driver. This allows the driver to chop the on/off time of the coils in the motor to regulate to the desired set current rating of the motor. As the motor moves and commutates (switches the 2 phases on and off) the faster you go, the more the inductance rating of the motor tries to limit current impulse through the coil and thus the drivers can modify the on time (PWM) to keep the current near the desired setpoint during high speed motion. Obviously, there is a limit and we know this as the speed VS torque curve.
The point being, the driver is actively sensing the current through the coil. If you disconnect the coil while energized, this can destabilize the current feedback loop and the driver self destructs. And note, it's not just the output wires, but also the input wires. This is why you NEVER put a switch between the PSU and the driver. Opening and closing that switch during operation can lead to a massive voltage spike that blows the system sky high as well.