[tamtoucan]

I bought a CN3018 and it works fine, however I then fitted the ER11A holder and the motor pulses i.e. it starts to spins then stops, then starts again, stops etc.

If I unscrew the bottom of the ER11A then the motor spins fine, so I assume the extra weight of the ER11A is just slightly too much for the supply. The kit came with a 24V 4A supply, I had a 24V 5A which I've tried but it doesn't work either.

Any suggestions on a supply to get?
Thanks.

[john-100]

I assume your 24V supplies are switch mode power supplies

does the CN3018 have a speed control for the spindle motor or just on/off control ?

if it only has on/off control ,
the higher the inrush current with the extra inertia must be tripping the power supply over current protection

what does the control board look like ?

John

[tamtoucan]

No they're just power adapter type (like a laptop charger). The 3018 has no speed control, you can see the power control here
https://www.youtube.com/watch?v=hB4Cvbtu-lA&t=1m22s

[underthetire]

I'm thinking your GRBL settings are wrong. I used to have one of these but slightly smaller I gave my nephew, and it had the same power supply and had no problems turning with a ER11. I did have the woodpecker board version though with PWM spindle control, but same laptop supply.

[john-100]

now I can see the original CNC 3018 board
Attachment 424768
just has on/off control of the spindle

what happens with if you unplug the 3 stepper motors to reduce the load on the power supply ?

if that works
what's the output voltage at the spindle motor terminals ?

may be you can use an extra relay connected to the control board motor terminals to switch a second power supply to switch the spindle motor on and off

or replace the control board with the later version

Attachment 424766

John

[tamtoucan]

Still doesn't work with the motors off. However with the motors off and the collet off, but the nut part still on (so slightly less weight) it does work. The voltage across the the terminals is 24.6V
Thanks.

[tamtoucan]

Just to say for anyone finding this thread I bought a cheap 24V 15A power supply and it now spins fine.

[john-100]

good to see you have it working
it looks like the higher the inrush current due to the extra inertia was tripping the original power supply over current protection as expected

John