Speed Control for DC Motors/Speed Controllers

[arturoduncan]

Some have asked on how to wire a DC Speed Controller to the MASSO. These speed controllers usually take AC voltage, rectify it and supply voltage to a DC motor which varies proportionally to the commanded speed. The problem with this speed controllers, is that the negative of the motor becomes common with the common for the analog and PWM control signals as they are not isolated and will damage the MASSO if trying to use it to control the spindle speed that comes with the MASSO.

Smaller chineese import machines, like Grizzly, Harbor Freight, Littlemachine shop come fitted with these speed controllers. Some very poplar models are the KB120 from KB Electronics or the MINARIK.

I posted a wiring diagram in our website on how to use a C41S to control these speed controllers:

https://cnc4pc.com/c41s-pwm-variable-speed-control-board.html

http://cnc4pc.com/Tech_Docs/WS_57.pdf

In our website we have wiring diagrams available for different speed controllers. Feel free to post questions on specific controllers here or open a ticket in our website for support.

https://cnc4pc.com/contact/

Arturo Duncan

https://cnc4pc.com

 

[skibbe]

Thanks for posting this, @arturoduncan. I need just this solution for converting a LabVolt (Sherline) machine which appears to be using a 0-10V input to the existing spindle driver cards. I picked up a C41S per your recommendation and am just starting to wire it into the MASSO.

Wish me luck!

 

[arturoduncan]

Let me know if you need help with this.

 

[shaun]

https://www.homanndesigns.com/index.php?main_page=product_info&products_id=21

I used one of these on my Sieg SX2 mini mill conversion.



Same idea. Homann Designs is Australian based too, so might be useful to Aussies. Getting parts from the US can be slow and expensive.



Cheers!

Shaun

 

[dup]

Hi @arturoduncan

Can I use the C41S-PWM VARIABLE SPEED CONTROLL BOARD to control spindle speed on my Sherline mill. If so,could you assist with a complete wiring diagram to achieve this. Also will the M03 and M05 commands switch spindle on and off. I did follow the links you gave but could not find this exact board.

Thank you

Regards

Andre

 

[arturoduncan]

Yes, it is very doable. The Sherline Speed Controller is aKB120. Follow this wiring diagram: https://www.cnc4pc.com/pub/media/productattachments/files/c41r2_and_kb120_v1.pdf

 

[dup]

Hi Arturo

My C41s rev 1.1 control board finally arrived....Thank you

Just to refresh...I am wanting to connect the Sherline DC motor to my Masso to give me spindle control. On one of your wiring diagrams you show a 5V power supply to the C41s board.

I have a 24V power supply to my Masso. Can I take power from here to the board. I see there is a 2 pin connector block marked 12v/24v/gnd which is next to the 5v/gnd 2 pin connector block.

Or must I have a separate power supply to the board.

Thank Arturo

Regards

Andre

 

[arturoduncan]

Andre,

The C41S does require a +5vdc power supply that can deliver up to 300mA. The board cannot be powered with +24vdc.

Here are some ideas:

• You could steal +5vdc from the MASSO's USB port as it only uses 300mA.
  
• You could use an old cell phone charger.
  
• Get a standard +5vdc power supply.
  

I am getting notifications from this channel, so do not hesitate in contacting me through here is you have additional questions.

Arturo Duncan

 

[dup]

Thank you Arturo. So I hooked the CS41 board up with a variable power supply set at 5V for now and completed the wiring as per your diagrams to the Masso and the Sherline board attached to the motor.

Guess what? It works!!! M03 and M05 start and stop the spindle. Speed commands (S1500 M03)vary the speed of the motor accordingly. However, I am not sure that I am getting full revs from the motor

by just comparing a standard Sherline motor,s sound at full RPM compared with the one running on the CS41 board and Masso. Unfortunately the encoder on the mill software is not yet operational and so I cannot

see on the screen what RPM the spindle is actually doing. I shall need to order a 5V power supply once the lock down is over

Thank you for your help Arturo

Regards

Andre

 

[arturoduncan]

Andre,

Thanks for the feedback. To verify the speed controller is getting the appropriate voltage, measure the voltage across P1 and P3 of the original speed controller and that would be voltage that P2 is expecting to deliver full speed. Then verify the voltage the C41S is putting out.

Arturo Duncan

Welcome to CNC4PC

cnc4pc.com