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I'm testing a stepper motor (NEMA 34, variable 30-100v, 6 amp stall current). I'm using a variable DC power supply (Korad KD3005D, up to 30v, 5A) to power it. When I supply power to the motor (through the driver, 2HSS86 hybrid driver), as I increase the voltage, at around 15v, the constant voltage (cv) and constant current (cc) LED indicators start to blink (first one, then the other) and the power supply makes clicking noises in time with the lights. The motor driver LEDs (power and alarm) flash with the same pattern. This continues as I raise the voltage up to the power supply's peak 30v (which is within the motor's voltage requirement).

Just to make sure the DC power supply wasn't bad, I hooked the motor up to another one in the lab I work in (Kungber SPS605, variable 60v, 5A). It started spinning at around 15v. No lights or clicks. I think this means the wiring between the motor and driver is fine, it's MY power supply that is being silly.

This is my first time using a DC power supply and a stepper motor, so I'm not sure if my unit has some sort of special safety feature or if it's just bad.

Any idea which it is? Do I need to push the buttons in a different way or get a new one?

The manual is pretty sparse, and I couldn't find any alarm codes or fault indicators: https://www.sra-shops.com/pub/media/docs/srasolder/instructions/kd3005d-user-manual.pdf

Here's the unit: https://www.sra-solder.com/korad-kd3005d-precision-variable-adjustable-30v-5a-dc-linear-power-supply-digital-regulated-lab-grade

And the power supply in my lab: https://www.amazon.com/dp/B08DJ1M42H/ref=cm_sw_r_apan_glt_fabc_1VEQRB9AH6DAW38V7GBV?_encoding=UTF8&fbclid=IwAR1S-_1Qp2b2SUkekjaoMF6xVkpeW89uRI7SjeHTqcfbTtp_SvHPR-p_L9c&th=1

Thanks!

asultan
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Your motor driver is pulsing (pwm) the current to the motor and is insufficiently filtering the input power. This causes the current pulses to continue to the power supply.
Not much of a problem on a open frame power supply without current limiting and hickup protection, as is typically used for drivers, eg: meanwell.

A bit of a problem with a power supply that switches to constant-current when you go over the set limit. It probably also causes the internal transformer tap switching to go clickety-click-click.

Try to set the allowed current to the maximum of the power supply, if it still triggers the CC, then consider adding a power supply filter with a decent capacitor (several hundred uF) to the motor driver.

Jeroen3
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  • Thanks for the quick response! I want to make sure I understand what you're suggesting before I go for it; please forgive my lack of experience! Are you suggesting I set my power supply to it's maximum current setting (5 amps) in "constant current" mode to power the motor driver? – asultan Aug 19 '21 at 23:37