Boy says it hits a limit switch

[bill_moore]

I have my new bot up and running. I am slowly going around the learning curve. One problem happens EVERY time I use it. After less than a minute into each project it stops and the hit limit switch bubble apears on the monitor and I'm not near one.I hit resume and it finishes the cuts but it is overriden and I would rather find out why instead of risking disaster running it without the safety of the limit switches. Any suggestions.
Thanks

[bill_moore]

I didn't proof read that very good. BOT hits limit switch DUH

[drodda]

When it says this does the red light on the limit switch actually come on?

[rob_jones]

Go to C:\program files and delete the folder "Shopbot" use your CD to re-install the software. If you have the code numbers handy, it shouldn't take too long to do this. This is what solved it for me.

[paco]

This might a case of false trigger. The sensor/switch get a very short signal from electrical noise or static and it's enough for the control software to assume a limit switch trigger.

You can try running the tool without dust collector, then no spindle/router running, then no vacuum, then disconnect the proximity/limit switch to sort out the cause of the problem.

This was my fix...


8011

... you may want to contact SB support for update on this regarding current control box. It's actually advisable to have such a filter to cancel false trigger. This wont block real trigger.

[bill_moore]

Thanks to all that responded.
Reloaded control files: no help
No vac: no help
Dave : The only indication I get besides the limit warning is the green lights on 2&3 turn yellow for a moment then back to normal.
Paco: thanks I will check with shopbot on my setup. That is close to over my head in electronic knowledge. I wouldn't even know where to get those items. Radio Shack?
Thanks

[Gary Campbell]

Bill...
I bought mine at Radio shack using SB Tech Supt specs. Dont know if the new boards need them. We had numerous stop switch hits and lost position errors. Read this post, it may help.
http://www.talkshopbot.com/forum/messages/26/23079.html?1194144245
Gary

[zeykr]

Shake the wire a little right at the prox switch while watching the input lights. I've seen one bad prox switch on an alpha and it was inside the switch somehow - movement of the machine would set it off occcasionally.

[bill_moore]

Talked with ShopBot today. They suspected a switch as Ken suggested. Did some troubleshooting by disconnecting 1 at a time. The X axis switch was the culprit. New on on the way.

[phardy79]

I am having the same problem as described. What kind of machine are you running?

[sagreen83]

I am having this problem as well. My machine at random times says that it has hit a limit. This all started soon after I upgraded to a Spindle and 7.2 motors. I'm going to try the cap / resistor thing to see if that helps.

Scott...

[andre]

Ok this is a strange coincidence
This week my prs alpha was possessed and was doing things like stopping in the middle of a file but the router would stay on. then it would lose its com port connection and could not find it again until i rebooted. First problem was a shorted prox switch. I disconnected it and the problems continued with hitting limits in the middle of the table and then resetting its location where it stopped. I tried to jog home after one of these incidents and the router plunged through my spoil board and 1/2 way through the plenum. After 2 days of head scratching, calling Sb and talking to Scott, and some choice words to my self, I discovered several things, first, was dust in my computers MOBO which must have been causing the Sb to loose port connection. Second the grounding wire on my dust hose to the router was disconnected, causing static elctricity, which was causing communication problems, and 3rd, I have an electric heater in my office 20 feet away which may have been causing electric noise and interfereing with things. Any ways I thought I would share. Hopefully the problems are gone, I will see this weekend.

[bill_moore]

Paul I have a new PRS Alpha 2 months old. Got the new switch today. If you troubleshoot by disconnecting 1 at a time you need to change the one you disconnect to normally open in the control panel.

[bill_moore]

Scott & Andre
My spindel stays running and when I hit resume it finishes the job with no further problems. The light in the switches do not go out. Shopbot said they have had several switches that are bad internaly lately. I will install it tomorrow and report the results

[andre]

Bill
the first prob i was having was that the machine would just stop with no error report and the router would stay on, even after I closed down the control software. I had to shut the box off and then reboot the computer in order for it to find the machine again. One instance the control software showed the tool was still moving but it was not. Ghost in the machine?
I dont think this part of my problems was due to the prox switch, I think it was computer issues.
This stuff is a pain in the you know what but teaches you something. ( I'm not sure what yet, but I will let you know

[bill_moore]

Andre Mine did the exact same thing when moving in keypad mode though. If cutting or moving on command it said it hit a limit. I put my new X position switch in today and everything I did after that worked perfectly. I would recomend you eliminate them as the cause before you do too much

[andre]

Bill
I think I did fix that problem.
I'm not getting prox switch warnings any more. The machine would just stop with no warning windows indicating why. I did some air cuts with a table surface routine and things moved fine. I regrounded the dust hose and the table itself. I will be cutting some stuff this weekend, so I will see then.