Centroid Community CNC Support Forum

Upnorth wrote: ↑Mon Jul 18, 2022 5:40 am I think the increment on mine is .0005". A complete rotation of the needle is .030".

I looked them up, probably worth having one at at some point. thanks for the input on these I did not know they existed.

martyscncgarage wrote: ↑Mon Jul 18, 2022 5:44 am It looks like the spindle speed range for the Sherline with the belt in the "Normal" pulley position is about 75-2800RPM. You have 0 programmed in the Min Spindle High Range in the Wizard.
When you ran the spindle bench test, I assume you had no wires connected to Spindle Analog output other than your meter correct? Do not try and run the spindle speed bench test with it connected to the KBSI-240D

Here is an old video I made setting up a KB Electronics Drive:


You need to make sure that the drive itself has all its pots set to the factory settings first. (WHICH KB Electronics drive are you using?) I see you are using the KBSI-240D Signal Isolator.


DO keep in mind that an encoder on the spindle does not close the spindle speed loop in CNC12. That is, if you call an M3S1000, CNC12 does not attempt to maintain 1000rpm at the spindle. The purpose of the encoder is to display actual spindle speed and to slave the Z axis for tapping and threading.

DC Drives can be finicky to setup.

You might run your spindle speed bench test again, with and without the KBSI-240D analog inputs connected to Acorn to see how close the values are as well. (the may differ slightly)

Marty

I provided all the docs for all the speed control components in my systems. The DC drive is a KBIC SCR DC Motor Speed Control Which is the original Sherline OEM motor speed control, that originally was used manually. I need to look to see the exact model I'm not sure. ?

I will get in touch with KB again see what input they have, Also Sherline.

BillB wrote: ↑Mon Jul 18, 2022 12:43 pm

Upnorth wrote: ↑Mon Jul 18, 2022 5:40 am I think the increment on mine is .0005". A complete rotation of the needle is .030".

I looked them up, probably worth having one at at some point. thanks for the input on these I did not know they existed.

They have many uses but in my case are most often used to align the fixed vise jaw on the milling machine. Very accurate.

My personal favorite of dial test indicators is the Interapid 312B-3. It is a 0.0001 (0.004" per rev) DTI but has the most "travel" of all of the tenths indicators - 0.016" total.
https://www.mcmaster.com/19515A53/
https://www.mscdirect.com/product/details/06442842

The only thing that I do not like about it is the stem type mounting instead of a dovetail. Here's my fix:

[/quote]


I provided all the docs for all the speed control components in my systems. The DC drive is a KBIC SCR DC Motor Speed Control Which is the original Sherline OEM motor speed control, that originally was used manually. I need to look to see the exact model I'm not sure. ?

I will get in touch with KB again see what input they have, Also Sherline.
[/quote]

You did.
Point being is that if you have 0-10VDC going into the KBSI-240D, it should come out nearly the same going to your KBIC speed controller.
Spindle Speed adjustments should be done on the KBIC drive itself.

Marty

martyscncgarage wrote: ↑Mon Jul 18, 2022 5:12 pm

I provided all the docs for all the speed control components in my systems. The DC drive is a KBIC SCR DC Motor Speed Control Which is the original Sherline OEM motor speed control, that originally was used manually. I need to look to see the exact model I'm not sure. ?

I will get in touch with KB again see what input they have, Also Sherline.
[/quote]

You did.
Point being is that if you have 0-10VDC going into the KBSI-240D, it should come out nearly the same going to your KBIC speed controller.
Spindle Speed adjustments should be done on the KBIC drive itself.

Marty
[/quote]

Wait a min is this a typo? All the adjustments we have been making are via the min & max pots on the KBSI240D not on the KBIC board? We did look at that BUT the pots on the KBIC board seam to be fixed in place by the factory. In fact my friend broke one trying to turn it. IF that is the case how do you dial in the KBSI 240D before you dial in the KBIC? Where do you start on the KBSI 240d?

BillB wrote: ↑Mon Jul 18, 2022 11:42 pm

martyscncgarage wrote: ↑Mon Jul 18, 2022 5:12 pm

I provided all the docs for all the speed control components in my systems. The DC drive is a KBIC SCR DC Motor Speed Control Which is the original Sherline OEM motor speed control, that originally was used manually. I need to look to see the exact model I'm not sure. ?

I will get in touch with KB again see what input they have, Also Sherline.

You did.
Point being is that if you have 0-10VDC going into the KBSI-240D, it should come out nearly the same going to your KBIC speed controller.
Spindle Speed adjustments should be done on the KBIC drive itself.

Marty
[/quote]

Wait a min is this a typo? All the adjustments we have been making are via the min & max pots on the KBSI240D not on the KBIC board? We did look at that BUT the pots on the KBIC board seam to be fixed in place by the factory. In fact my friend broke one trying to turn it. IF that is the case how do you dial in the KBSI 240D before you dial in the KBIC? Where do you start on the KBSI 240d?
[/quote]


The primary job of the KBSI-240D does is isolate the control signal (0-10VDC in this case) signal and allow the user some flexibility on the input and output signals.
From the manual, http://www.kbelectronics.com/data_sheets/kbsi240d.pdf:
"The KBSI-240D Signal Isolator is used to isolate, amplify and condition DC voltage and current signals from any source (motors, tachs and transducers) which will drive most variable speed motor controls with a voltage following input."

The Sherline KBIC controller likely use a potentiometer previously to control speed. Now you are using a 0-10VDC analog signal to control motor speed.
The KBSI-240D needs to be setup to use voltage following (J1 set to VOLT) and to take Acorn's 0-10VDC analog input and output the same 0-10VDC You will use its min/max speed pots to adjust the output to be close to the input voltages. For example, if Acorn spindle analog output is 1V, then you want the KBSI-240D to be 1V. If Acorn spindle analog output is 5V then you want KBSI-240D to be 5V

Sounds to me like Sherline glued the speed pots on the KBIC speed controller, so once they were adjusted at the factory, the user could not adjust them.
While I understand why that did that, it was a mistake because now the KBIC drive input signal is different than what was originally used and needs to be adjusted like I did in the video. The drive I used in the video had a signal isolator designed to be plugged on the drive itself. (If you have a KBIC drive, I believe its companion Signal Isolator is the SI-5. That why I asked for the model number of the drive. There is usually a label on the end of the drive with that information) This is an example: https://www.ebay.com/itm/275352784685

Per the KBSI-240D Manual: https://acim.nidec.com/drives/kbelectro ... anual.ashx
(take a look at pages 7 & 8)

Acorn should be connected to KBSI-240D input terminals 5(AN Ground) and 6(AN Out)
KBSI-240D analog output to your KBIC drive should be 9(-) and 10 (+)

Do this,
Disconnect the KBSI-240 from the KBIC Speed control by disconnecting the KBIC from terminals 9 and 10.
Go into the Wizard, set the max spindle RPM to 10,000 (every 1,000rpm will equal about 1VDC)
Power up the KBSI-240D
Put your meter on Terminals 9(-) and 10(+)

Reset CNC12 to put it in the ready state.
Home the machine
Go into MDI
Call up M5
That should be very close to 0V
Check the meter, what does it read?
(Adjust the min trim pot on KBSI-240D to get it close to 0V)

Call up M3S10000, that should be about 10V
Check the meter, what does it read?
Adjust the KBSI-240D MAX Trim pot until you get it as close to 10VDC as you can.

Now call up M3 S5000, that should be about 5V
Check the meter, what does it read?
It should be fairly close to 5V or so

KBSI-240D should be now calibrated to accept a 0-10VDC input and output the same. Now you have to calibrate the KBIC speed controller like i did in the video.

Hope this helps.....
Marty

The latest development on my build is now my lathe Acorn is dead. Saturday we ran both machines and controls all day trying to get the spindles dialed. All was good. Sunday I go out to the shop and power up both controls and lathe Acorn is completely dead, I check around for disconnected plugs then take some voltage readings and figure it’s the PSU because I’m getting no voltage to v1or2 & com on PSU. I contact Centroid Monday they send me out a new PSU, (thanks guys) I install it tonight, still dead! WTF!!!! Sorry so frustrated?!!!! I check voltage on main 24v & com connections on Acorn H9 and H4, nothing but its jumping from 0 to maybe a 1 1/2 V but nothing steady, no voltage on my terminal blocks, and no voltage at the NEW PSU. HOW is that possible? I checked V1&V2 & COM. On V1 I get a jumping voltage from 0 to 2.5 or so nothing steady and not the 5Volts that leg should have. Green LED on PSU is flashing not solid like it should be. And I have no LEDs at all on Acorn.

I checked continuity on the PSU power cord it is good. I didn’t not check AC lines coming into the PSU not ready to start poking around AC just yet

Is this Acorn toast?

But wait it gets even better. I go to work on the mill and now I have no spindle running on that control when just the day before I did! Is the KBIC dead on this one?

My friend questioned if we had a power serge or brown out in our area, how can I have 2 major failures over night ? I have no idea.
Everything is only plugged into standard plug strips, no surge protectors?

Disconnect all from the acorn board and plug in only the PSU.

If one of the Inputs is shorted, acorn will not start.

Uwe