limit swithes

[mikee]

 not sure where to start
  i have a intermittent problem with limit switches  (EMG RESET limit switch triggered)
  this is the part that is getting me  nothing is lighting up on the diagnostics board
  switches are wired to N/O    help please    i think it is the choice of pins that i am using or the PC is using  i have tried everthing
 

 mikee
 not much land dam few cattle co

[Cosha]

Im not sure , but it sounds like your cables to the limit switches are not shielded?

I think CNC machines put out alot of 'Electrical Noise' that can fool Mach3 into thinking a switch has been hit...


Im *Sure* if you look for a 'Debounce' Setting and change the value to around 2500-3000 it will be fine!

Hope i right, this could be the most useful post i have made to anyone here 

[Cosha]

From Other Sorces On The Interweb


Use Mach 3 Debounce

I put this one first because it is easy to try. Limits and similar inputs can be debounced in software using Mach 3. This can help to reduce noise sensitivity. Most sources recommend trying a debounce value of 1000 to see if it improves the situation. Values as high as 2000 are sometimes recommended.

Sometimes this debounce option can cause problems in homing circuits, such as strange reversals of motion, so be on the lookout. It is not a panacea. Lower values of debounce may make your switches more accurate and repeatable. It's worth experimenting to find the optimum lowest value that eliminates false hits from noise.
http://www.cnccookbook.com/CCCNCNoise.html




Mayve the 2500-3000 value is a little high, so try from low and work your way up?

Also, note that if it is noise from the machine try and run your signal wires and motor wires on different routes, or try get as much distace between them

[mikee]

  index debounce and debounce intervals put 2500 in both boxes no change
 I'm getting my butt kicked bad
 I'm about as new to mach3 and machining  as they get
 hard to explain
 I'm getting the emg limit switch  trigger    i get this when there is no power going to my AC 110 to 36 DCV converter  nothing else is on except 5 DCV usb port cable to break out board that the 5 DCV that powers the limit switched .there is also like 2 or 3 DC/v  coming from PC to break out board through parallel cable.
 at first it was just z axis   now it all of them i if i go through and auto set  X and Y axis  get to z axis I'm done on any pin  still hard to explain 
removed Z axis wires  from break out board   
enable z axis limits switches  and touch z axis limit switch post on break out board  24 GA wire 10 ft long not hooked up on other end of wire   limit switch trips emg  no light on diagnostic board cannot reset hard fault  but no lights diagnostic screen 
 and i dont know enough to run without limit switches at first i thought it was my wires too or switches
 i have wired normally open on my switches now i would wire to normally closed but if i cant even hook a wire up to the breakout board   i don't have a shielded wires on my limits i will re wire tomorrow with the right wire
and go to normally close on my limits
 this is  a do it yourself with without instructions manual  cnc router  lol   i think this problem is in the pc or the pin choice
 thank yoyu dont give up on this please
mikee
                     

[mikee]

 this the first time this cnc has ever moved im sorry for poor information
mikee

[mikee]

  you might be right  possible internet router putting out wirerless signals to other PC's
was about 1 foot from controler box  speakers for PC has popping noise
 popping sound matches  leds on front of internet router blinking on and off
 i will know more in next day or so
  mikee
 

[budman68]

Mikee,

When having so many issues, possibly you should look into keeping one PC for your machine, and another for all internet and design work. Wireless accessories can cause many noise problems whether it be for internet or keyboards and mice.

As for the Machine PC, not sure what OS you're running, but you may want to look into optimizing the PC to run more smoothly. Have a look here:

http://www.machsupport.com/downloads/XP_Optimization.txt

Dave

[mikee]

 thanks Dave and Cosha
  i think you are right.
 that my plan right after i get everthing set up this PC is going off internet ( was) (new plan) get out dell PC with (widows vista yuk) put it on line take this PC  strip it down just for mach 3 and addons, cam bam lazycam thinking of a good carve software too and if that dose not work i will buy a new PC   
  i ordered double strand shielded  22 GA cable or wire 
 i have x and y limits working for now! 
 the weird stuff has seemed to stop 
 but i going to wire z back up to the switches .
i think  need the signal so i can (ref all to home) in the (machine cord)  watch limit video 20 times i not sure what i am missing butt i missing the point on allot of stuff  it is very embarrassing
 i have never worked with shielded cable before. and paid much attention to it
 but i am going to change to a (normally closed system ) on my limit switches
 there (was) a issue with my PC utility. I hope i got it .
 everything is  complex to me and if i don't have the switches  I'm going to destroy my cnc .
 also going to do a better ground system 
 If there any suggestions  keep me  track
 thank you for your help Dave and Cosha
 i ask if someone could  give me example of pin order for 3 axis  X++ X-- X home Y++ Y--Y home Z++ Z-- Z home  when i auto set it will use #10 pin 3 to 5 times  i don't know the right  combination  for sure
In diagnostics screen limit triggered hard fault might light up on more than its Axis row
I'm not using coolant pump spindle motors .
mikee
not much land dam few cattle co. (less land) river still rising. barn floor is mud now 
 

   

[Cosha]

Do not panic & start ripping wires out here and there 

I brought a PC base from E-Bay, Windows 2000 Cd Rom and a hard Drive for £15, you dont need a singing all dancing PC to run Mach3

I had lots of trouble when i was starting out and i still do, so dont feel too bad!

Can we have more information on your controller board, any manuals on the interweb?

[mikee]

 i wood be happy to tell you if i new
if you go to build your own cnc i have the 2x4 black toe except i made my table 8 ft long i have 74.5 x axis 24in y axis
about 6 inch z axis any way you would have to see from there kits   i have specifications 5vdc relay and i have 4 limit switches inputs  and   support mach3
 i think i learned something that i don't have enough pins to do everything on limits and home
   break out board 5 axis 36 volt drivers at 1.5 amps  5vdc usb port 1 parallel cable i haven't
  ripped wires out yet
  no  ( no manuals) that would of been way to easy . i got caught between new electronics  and old video' no man land
the only reason i have made it this far is because of this web site and all the help in here.
 every thing has seemed to settle down x and y limits are working .
 thank you
waiting on 22/2 shielded cable
 mikee
not much land dam few cattle