Centroid Community CNC Support Forum

Hello
I can use some help


I'm in the process of building up a Sherline Ball-Screw Mill with an Acorn setup and purchased a KP-1 probe.

I purchased the Probe new from the Centroid shop this past Dec but wasn't able to test it until this past weekend. I have been assembling parts over the past year and testing the Mill and now ready to try the probe. The probe was stored vertical as per the manual.

I was running an older version of CNC 12 previously but just upgraded to CNC v5.30 in order to see the KP-1 option in the probe menu. I have the Pro license installed. I have read through the documentation and unable to get the probe to function. It reports errors no matter what I try.

I'm using the KP-1 Flying lead cable I purchased with the Probe.


I attached an image I created showing the exact wire connections to the acorn board and pictures of the probe hooked up along with error messages. I noticed Centroid soldered lead wires to the end of the stock cable they sell so I removed the shrink wrap and carefully checked the spliced wire area for any damage to make sure that was not an issue. I show the wire setup that came with the cable to verify it's correct. I noticed the stock plug wires are Black, Red, White and Green with a bare metal ground wire. Centroid splices pigtail wires to the cable with (red -to- red, black -to- black, white -to- white, green -to- yellow and bare metal -to- Green.


Using a multi-meter, I tested continuity on the pigtail leads with the cable plugged into the Probe (Not powered up). With the probe in rest (No deflection) I see continuity with the Black and Yellow wires. When I press on the probe ball, I see the same continuity between Black and Yellow wires. No other wires show any continuity in rest or deflection of the probe ball.

With the probe connected to the acorn, the Green light is shown in rest. When deflected the red light turns on and will return to green when the probe is released again.


I'm not sure if there is something wrong with the Probe, or I'm simply missing a setup step somewhere in the software, wire connections etc. Not sure what to test next?

Thanks

Don't you need a +24v supply wiring to the H1 "24 IN" connector so it has a voltage reference signal to pick up the probe detect and probe signal? Sorry I have an Acorn6 so might be different but that is the case for the 6.

Wiring:

https://www.centroidcnc.com/dealersuppo ... 262.r1.pdf

Yes there must be +24V on 24 IN, otherwise the inputs will not work.

Uwe

Here's a schematic for Acorn and KP-1 that includes the power supply:
https://www.centroidcnc.com/centroid_di ... erm=S15261

Hello,

I agree with the others - you need to have +24V going to tone of the 24IN terminals on the input headers.
I would also make sure to check your force/invert settings on the inputs - the behavior seems a little odd even considering that the inputs are floating.

Several things to note:
KP-1 will have continuity between the yellow and black wires all of the time. They are shorted internally and provide the probe detection signal.

Without powering the probe, you will not see any other continuity. When the probe has +12 to +24 VDC between the red and black wires, you will be able to measure continuity (if not connected to a PLC input) or voltage changes from the white to black wires when the probe is tripped.

Hello
Thanks for reply’s

My schematic above was only showing the probe wiring and was not a complete drawing. Sorry for confusion.

A full schematic for the board and back panel can be found here:

https://www.sherline.com/wp-content/upl ... config.pdf?

This acorn was purchased from Sherline and wired by them.

I also attached a closeup of the lower power hookup here to help show how my board is powered


From the DB9 plug, I verified inside it connects to Acorn

Pins
1 - IN5
2 - IN6
3 - IN7
4 - Empty no wire
5 - Ground Chassis H9
6 - Empty no wire
7 - Empty no wire
8 - 24v H9
9 - COM H9

Green is not tripped and red is tripped.

Make sure with ALT+I the Probe Tripped Input is changing if the probe is red (tripped)

Uwe

Tested in PLC debug menu tonight

Software settings
Inputs:
IN6 - Probe Detect
IN7 - Probe Tripped

Probe Configuration:
I selected KP-1 Probe from the drop down menu


First image has no changes in PLC menu
Second image shows results after I inverted IN7 in PLC

I attached a 3rd image from the KP-1 manual showing what a working probe should look like.

All my images have a variety of items that are different from the manual. For example the "Probe Detected Spindle Inhibited" message should appear in both rest and tripped conditions. That message only shows up when probe is deflected in both examples. The little dot on the probe graphic in the software should change colors (Green/Red) as shown in the manual similar to the LED light on the probe. Mine stays the same color in rest and tripped conditions, etc.


Could I have received a bad Probe? What would happen if the wire for IN6 and IN7 were flipped inside my probe cable for example, could that cause these issues? Not sure what I should test next.


Thanks for everyone's help.

It looks to me like when you trip the probe it's changing input 6?
What if you go in the wizard and swap input 6 and 7 around?

When plugged in, "ProbeDetect" input should be green at all times
When not tripped, ""ProbeTripped" input should be green
When tripped, "ProbeTripped" input should be red

It looks like the signals are somehow switched even though your cable matches my schematic. I recommend double checking your wiring to that DE9 connector.

Does it behave the same if you flip the USB-C connector 180 degrees and re-insert? This will show if there is an issue with the connections between the USB-C header and the board. Cables typically have wires on only one side of the connector so flipping it over will use the other contacts on the header.

Regardless, I'm not sure how such an issue would have made it past our production testing. The KP-1 PCB is tested after the components are populated, the cables are tested after assembly, and the probe itself goes through a comprehensive test as well.