Machsupport Forum

Mach Discussion => General Mach Discussion => Topic started by: jagert59 on April 13, 2009, 08:26:02 PM

Title: Hurco proximity style limit switch problems
Post by: jagert59 on April 13, 2009, 08:26:02 PM

I have a 1984 Hurco SM1 with the stock proximity style limit switches that were functioning prior to replacing the Hurco control with Mach3.  I am using a CNC4PC C23 breakout board, Smooth stepper, Viper200 servo drives.  The problem I am having is I have 5v going to the limit switches, as checked with a meter, but when I trigger one of the limit switches, doesn't matter which one, I don't get any voltage back from the limit.  I have attached a scan of the Hurco wiring diagram for reference.  Any help would be appreciated.

Tom

(http://i285.photobucket.com/albums/ll74/tjs80cj/CNC/SCAN0001.jpg)

Title: Re: Hurco proximity style limit switch problems
Post by: jimpinder on April 14, 2009, 03:05:36 AM

The diagram (on which I can only see the X axis limit, appears to have four wires to it. Yellow and black for the power, and the return is via the black and brown. I assume the second black wire is also at Ov potential as a reference for the brown wire. You do, however need some reference across to your breakout board for this to "spot" the voltages coming out.Unless you are using the rest of the board for some other purpose, I would do away with it. Power the switches directly from your 5 vlt/0v supply on your nreak out board, and take the return directly in.