connecting DC motor to acorn cnc analog output

[myths420]

hello im almost finished converting my mill to cnc with Centroid Acorn. I've followed the guide posted below. Now I've done a lot of research the last year prior to build and from my understanding one of the reasons people upgrade spindle motor to ac and vfd besides more speed is that vfd accepts 0-10v to work correctly while DC is 0-5. after hooking up an isolator board that seems to be bad and lots of time with the volt meter out i noticed Acorn CNC12 software has an option to reduce the 0-10 to 0-5v and noticed its outputting the same volts as the signal isolator does on different speeds. So with this setting enabled what would stop me from just using the Acorn spindle output? is this a new feature? as in the last year of research I've never come across anyone saying anything about this. They only just talk about dc doesn't accept 0-10v.

https://www.dropbox.com/scl/fo/r91o1pw1 ... cd513rwe3t

[cnckeith]

viewtopic.php?p=52936#p52936

[cnckeith]

viewtopic.php?f=61&t=2027&p=16108&hilit=kb#p16108

[martyscncgarage]

You mention nothing about the mill, no pictures, you don't say what spindle drive you have, what kind of spindle motor you have. We can not "See" what you "See"
Take pictures of everything, upload to a Google photo album and share a link here.

The only purpose for KBSI-240D is a signal isolator. The Acorn analog voltage level going into it should be very close to the same that comes out of it.

If you need 0-5vdc analog signal for your spindle drive, you have to select that in the Spindle section of the Acorn Wizard
Marty

[myths420]

You mention nothing about the mill, no pictures, you don't say what spindle drive you have, what kind of spindle motor you have. We can not "See" what you "See"
Take pictures of everything, upload to a Google photo album and share a link here.

The only purpose for KBSI-240D is a signal isolator. The Acorn analog voltage level going into it should be very close to the same that comes out of it.

If you need 0-5vdc analog signal for your spindle drive, you have to select that in the Spindle section of the Acorn Wizard
Marty

sorry i had thought the link i provided in post listed the mill details. its a pm-30 2hp dc motor and the control board regulates the speed with a 0-5v signal. so im mainly asking is their a purpose other than reducing a signal from 0-10v to 0-5 the signal isolator does sense acorn has a setting now to control 0-5 in software. when i purchased this control board a few months back i also broght this up with acorn support and was told the reason i would need a something else is because acorn is 0-10 so im guessing this must be a newer feature?

[myths420]

viewtopic.php?f=61&t=2027&p=16108&hilit=kb#p16108

ty i have watched alot of their videos and read documentation over the last few months but they are years old before acorn could reduce the spindle volts via the software. so now that this is an option trying to find out is there still a need to run the line threw these boards to reduce the volts.

[martyscncgarage]

viewtopic.php?f=61&t=2027&p=16108&hilit=kb#p16108

ty i have watched alot of their videos and read documentation over the last few months but they are years old before acorn could reduce the spindle volts via the software. so now that this is an option trying to find out is there still a need to run the line threw these boards to reduce the volts.

Again, WHAT version of software are you running? Get it up to date before moving forward. DO not install a new version over the top of the old version.
Hopefully you have taken screen shots of all your Wizard pages so you have them when you do a FRESH install.

You need to use the KBSI-240D or risk severely damaging Acorn.
I have seen users do it more than once.

Marty

[myths420]

the newest version im just starting my build. and yes i have seen people damaging boards because they were hooking dc motors up to 10v. my question is the same. if acorn can now supply just 5v. what exactly is the purpose of the kbsi board? from everyone who talks about it or writes about it the sole purpose is to convert a 10v signal down to 5 volt. also to convert signal to a +/- if its needed. as this board doesnt require the signal converted from my understanding. the only thing the kbsi does is the same thing acorn does now. so im trying to understand why its needed anymore?

[myths420]

i also already have the mill hooked up threw a kbsi-240D but it doesnt function correctly. if i unhook the kbsi from the mill i set the min to 0 and the max to 5.06. once i connect the board to mill it cannot be set to 0. it starts off at 2.5v and then goes to 5. lowering the volts on the min side only teleports the volts down to -47. cant be adjusted to 0 with a load on it. the volts also pulse between 2-4v by .2. very unsutable for milling. yes it is wired correctly. all volts going into kbsi are correct and stable as well.

[martyscncgarage]

the newest version im just starting my build. and yes i have seen people damaging boards because they were hooking dc motors up to 10v. my question is the same. if acorn can now supply just 5v. what exactly is the purpose of the kbsi board? from everyone who talks about it or writes about it the sole purpose is to convert a 10v signal down to 5 volt. also to convert signal to a +/- if its needed. as this board doesnt require the signal converted from my understanding. the only thing the kbsi does is the same thing acorn does now. so im trying to understand why its needed anymore?

Simply put you are connecting two different electrical systems. There can be a huge energy potential between the two that can cause damage to the circuitry. The KBSI-240D does exactly that. The two systems are never physically tied together. The board takes care of that.

Unless you get something from the manufacturer that ensures the DC motor controller you are connecting to has an isolated analog input, you should use the KBSI-240D. Otherwise, take the chance and let everyone here know how it works out or didn't work out. It could be a costly gamble.

Is your machine a Precision Matthews? Call them, ask their support staff. I always question Chinese quality drives. They will literally try and save a few cents on every board rather than designing them correctly.

Marty