Help with CandCNC Feather Touch Ohmic Sensor

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Njcnc
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Help with CandCNC Feather Touch Ohmic Sensor

Post by Njcnc »

Picked up one of these units for my homebrew table after looking around for an ohmic sensing unit. I have it wired up, put power to it, green light is on. I've wired a common from my BOB which is 5v and my float switch into the unit. When I trip the float switch, I can see in linuxcnc the signal go from false to true so all is well. When I trip the ohmic sensing, the sense light lights up orange but I get no output on the "Z home" orange wire.

Am I doing something wrong here? Is the unit supposed to pass the common pin through the Z home wire or something else? I flipped through the manual and couldn't find an explanation on the logic. Also tried to join the candcnc forum but keep getting errors so posting here.

Thanks in advance for any help.
-Stefan
tcaudle
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Re: Help with CandCNC Feather Touch Ohmic Sensor

Post by tcaudle »

The Output is am open collector transistor. The input has to have a pullup and it shorts it to common. A basic NPN typ configuration. Common is to the input common of the BoB.
Njcnc
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Re: Help with CandCNC Feather Touch Ohmic Sensor

Post by Njcnc »

Thanks for the info, just rewired and tested it now, works excellent.

Thanks again
Stefan
Njcnc
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Re: Help with CandCNC Feather Touch Ohmic Sensor

Post by Njcnc »

Disregard the bump, was having noise issues and was going to post for some help but found the issues with my logic, need a little debounce in one path is all.
tcaudle
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Re: Help with CandCNC Feather Touch Ohmic Sensor

Post by tcaudle »

Input to BoB must not be isolated or have noise suppression. Takes a LOT of noise to light an Opto!
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