Problem with the 500Wspindle and Ramps 1.6 plus start to reset

Hi all, please help.

I have the following problem with the 500 w spindle and Ramps 1.6 plus:

When the spindle does not work, the MPCNC works perfectly, when the spindle is switched on, the ramps start to reset.

Уou can see here:

My wiring schema:

I tried to feed Ramps with another 12V 6A power supply, like this:

The two power supplies were connected to different sockets, but the result was the same.

I’m just a hobbyist with electronics, but when I’ve had this kind of problem, my go-to solution is to add a capacitor. In this case, I’d put a capacitor between the screw terminals of the Ramps 1.6 board. Someone with more electronics education could probably give you better capacitor specification(s), but I would put on a 25V or better, 1000uf to 3300uf electrolytic capacitor.

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Or separate the lines mine are hung from above for the spindle stopped the problem for me :grinning:

If you had an oscilloscope and could see the waveform coming out of the spindle power supply you would understand why these spindles are so noisy electrically. Isolate the spindle power supply and wiring as much as possible from any and all control wiring, even going as far as using shielded cables to the spindle. Definitely do not cable wrap the spindle power wiring with the Z stepper wires :-).

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Hi guys, thanks

I will try everything, but I will start with the easiest.

I wrapped the cables very well, all the way. I don’t have oscilloscope.

I have a few questions because I know what the board does, but how it does is magic

Robert is that what you mean ?

Is 25V capacitor suitable for 12V power supply? (Question from a layman)

Could any of these do the job?

Capacitors are rated for the maximum voltage they are designed to handle. I’m just a hobbyist, but from my reading, you want to install capacitors with a rating of at least 1.5x the voltage you use in your project. That is why I suggested a 25V capacitor. If you happen to find a 35V or 50V or 100V capacitor, it will be bigger, more expensive, and work the same in a 12V circuit as a 25V capacitor. Note that the capacitors in the picture of your Ramps 1.6+ board are rated at 35V volts, though you are running the board at 12V. I’m guessing the board is rated to handle up to 24V.

I don’t have any engineering experience on how to determine the ideal size for the capacitor. I’m just guessing at 3300uf based on playing around with some projects. The next size up is 4700uf. I don’t think it can hurt to use a bigger capacitor, but bigger is more expensive, and if it is not needed…

Note the capacitor is intended to address the issue of a voltage drop due to the spindle kicking on. If a voltage drop is not the cause of your problem, it will not help. If the issue is a voltage drop, a smaller capacitor may not provide enough power to bridge the gap.

The capacitor there will absorb voltage spikes and fill in voltage drops (for a moment). It has to be a pretty big cap (in terms of farads) for a board like the ramps.

There should not be much getting through that mess to the ramps though. That is very surprising.

I understand, I’m going to try now. On Saturday I will be able to tell you the result.

That is not what I suggested…separate your spindle power feed from all other wiring. I doubt changing your power supply for another one will help, especially as one of your previous ones had a choke in the lead (who’s job it is to suppress wire borne noise from travelling up the power lines to your control board). A pound to a pinch of poo will have your problem being noise induced from the spindle power lines into the stepper wiring and hence into the MCU via the stepper drivers.

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Yes, I will, but I suspect that is not the only reason. The reboot occurred for the first time while the cables were scattered in all directions on the floor.
Question, is it possible to insulate the cable with metal foil, for example, as a coaxial cable.

You could also run a ground wire from the case of the spindle power supply to the spindle motor case to ground the motor

I find that when the spindle power supply is on set z fails. For sure caused by noise on the feed cable to the motor. I have strung the motor cable 180 degrees away from all the rest. Try two core shielded cable with the shield to ground on the supply. Should help


Hi guys, thank you all.

I figured it out.
First I separated the motor cables and z axis – it didn’t help.
Second I put a capacitor between the screw terminals of the Ramps 1.6 board. More precisely, I tried 3 different ones, 25V 3300µf, 25V4700µf and 35V 4700µf. Didn’t help, continues to reboot

I decided that the board was damaged, I had spare Arduino and Ramps boards, replaced them. Still restarting.

And then it dawned on me, on the remote control (seen in the video) besides the joystick and the screen I also put the potentiometer of the motor, you know for more convenience. I separated the cables of the potentiometer and the screen and … Eureka!!! …everything worked properly.