contactor and spindle board questions

[94cobra]

hey guys, been working on converting a manual mill to CNC. I purchased the acorn a little while back and got it all bench tested etc. I am installing all the electronics in a PC case and am getting close to finishing and have some questions that i cannot figure out. hopefully I can explain without confusion.

question #1 - the contactor switch I have is 24v activation as recommended by DMM, where I bought the servos. I was under the assumption I wanted the contactor to power the entire electronics system. If it requires 24v then the acorn power supply would need to be still powered on to be able to control it. Should I be using a 110v activation contactor since i will always have 110v inside the case to use? That was everything is controlled through the contactor including the acorn 24v supply?

question #2 - spindle control... I have 2 options it seems. a CNC4PC C6 board that will use 12v to power the board and a KBSI240D which runs with 110v power supply. I will be controlling the spindle speed aswell as direction. The KBSI is about 3 times the cost. Can you guys suggest which way to go on this or is it just a preference at this point?

thank you guys.

[cnckeith]

hello. chiming in on #1...take a look at the typical overall Acorn system schematic attached.

[DICKEYBIRD]

question #2 - spindle control... I have 2 options it seems. a CNC4PC C6 board that will use 12v to power the board and a KBSI240D which runs with 110v power supply. I will be controlling the spindle speed aswell as direction. The KBSI is about 3 times the cost. Can you guys suggest which way to go on this or is it just a preference at this point?

The KBCC-125R has it all, speed control, spindle reversing, braking, heat sink, etc. No worries about reversing w/back emf problems. It's hard (for me at least!) to design circuitry that handles DC motor spindle reversing via CNC in a manner that's free from worry about letting out the magic smoke. The KBCC/KBSI combo works well and used ones are available on ebay for reasonable prices.

Here's a link, 3rd post down: viewtopic.php?f=60&t=1594&start=10

[94cobra]

hello. chiming in on #1...take a look at the typical overall Acorn system schematic attached.

thank you!

[94cobra]

question #2 - spindle control... I have 2 options it seems. a CNC4PC C6 board that will use 12v to power the board and a KBSI240D which runs with 110v power supply. I will be controlling the spindle speed aswell as direction. The KBSI is about 3 times the cost. Can you guys suggest which way to go on this or is it just a preference at this point?

The KBCC-125R has it all, speed control, spindle reversing, braking, heat sink, etc. No worries about reversing w/back emf problems. It's hard (for me at least!) to design circuitry that handles DC motor spindle reversing via CNC in a manner that's free from worry about letting out the magic smoke. The KBCC/KBSI combo works well and used ones are available on ebay for reasonable prices.

Here's a link, 3rd post down: viewtopic.php?f=60&t=1594&start=10

I see that there is 2 KB boards used there. I had stumbled upon this diagram used to control a machine very similar to the one i am using and was hoping to wire it up the same, except using the supplied 8 relay board that was supplied with the acorn.

Do you see an issue wiring it up as shown in the attached diagram without the 125R board? Definitely dont wanna let that expensive smoke out!! lol

[94cobra]

Looks like the diagram didnt get added, here it is

spindle diagram

[GBCues]

Take a look at Gary Campbell's video here:
https://www.youtube.com/watch?v=-kiKIQrRgig&t=215s
It should help you with the contactor question.
HTH
Gary

[martyscncgarage]

Take a look at the schematic Keith posted. Use an Estop switch with two ND contact blocks. Put one NC contact in series with the circuit controlling the coil of your contactor, use the other NC contact block for the Acorn estop input.

Note in the Centroid schematic, they open the common the common that activates the digital inputs of the VFD through a normally open contact in the Estop contactor.

You show nothing telling Acorn that an Estop button has been activated.
Marty