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home/limit switch problems
« on: November 06, 2016, 12:11:10 PM »
Decided to go with PNP NO prox's for limit and home switch's. Using a C10 BOB, ive got the xyz+ wired together in parallel to one input, xyz- all have there own input but each switch is a shared limit/home switch. input resistor is set pull down. Powering the switch's with a 12vdc Omron power supply, 10kohm resistors between the prox signal cable and the input point. All in all these are working awful. In the diagnostic screen they flicker on and off, and I can change the rate of flicker by adjusting the debounce interval. with the debounce interval set to 50000, yes, you read that right, 50000, the flickering seems manageable. Thinking about abandoning the last 2 weekends of work and putting in dry contact micro switch's. wish I had a treid it before I ran all the cables in the cable track.
Whats the downside to having that high of debounce interval?
What am I doing wrong?

Offline ger21

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Re: home/limit switch problems
« Reply #1 on: November 06, 2016, 12:56:32 PM »
Quote
Whats the downside to having that high of debounce interval?
A lengthy delay before Mach3 sees the switch activation.

Quote
What am I doing wrong?

Shielding and/or grounding?
Gerry

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http://www.thecncwoodworker.com/2010.html

JointCAM Dovetail and Box Joint software
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Re: home/limit switch problems
« Reply #2 on: November 06, 2016, 01:26:20 PM »
noticed the long delay.......its to long to avoid a crash, can leave the debounce at 0, and change it every time I need to back of a switch????? haven't treid refercing yet, got the Z axis motion backwards..the prox cables are not shielded..................motor cables are, that's all that's running side by side in the track. if I switch to dry contact micro switches should those cables be shielded? do you think shielded prox cabels would fix it?

THANKS for your help!

Offline Davek0974

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Re: home/limit switch problems
« Reply #3 on: November 06, 2016, 02:02:30 PM »
if these are the cheap proxies  from eBay i had the same issue exactly - it only worked properly when i switched to a 24v supply to them.

It says 12-24v i think but they flickered like hell on 12v, perfect on 24.

What s the reason for the 10k on the inputs?

Offline ger21

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Re: home/limit switch problems
« Reply #4 on: November 06, 2016, 02:17:25 PM »
5V inputs
Gerry

2010 Screenset
http://www.thecncwoodworker.com/2010.html

JointCAM Dovetail and Box Joint software
http://www.g-forcecnc.com/jointcam.html

Offline Davek0974

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Re: home/limit switch problems
« Reply #5 on: November 06, 2016, 02:20:29 PM »
5V inputs

ah, ok.


;)

Thats why i prefer NPN - does not matter what the supply voltage is so going from 12 to 24v is easy.

Found an old video of my proxy weird behaviour...
https://youtu.be/S5PP5sQh5Vk
« Last Edit: November 06, 2016, 02:31:12 PM by Davek0974 »
Re: home/limit switch problems
« Reply #6 on: November 06, 2016, 03:00:15 PM »
So I could bump up the resistors to a 25kohm and switch to 24 vdc power supply. That would be the easiest since I already have the power supply, just need the resistors. That worked for you?

THANKS for the help!
Re: home/limit switch problems
« Reply #7 on: November 06, 2016, 03:05:33 PM »
my led's on the sensors don't flicker, its the indicators on the diagnostic screen in MACH3 that flicker. I bought them from Automation Direct. The installation was so clean with the 90 dgree screw on cable connectors. hate to tear them off. Think the 24vdc power supply and different resistors will work?

Offline Davek0974

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Re: home/limit switch problems
« Reply #8 on: November 06, 2016, 05:03:04 PM »
Hard to say - your case is a little difference as i used NPN and you have PNP, my led's flickered on the sensors, yours do not.

Might work but i have doubts due to your leds' not flickering.