Re: Fanuc 6M overtravel won't clear.

--- In CAD_CAM_EDM_DRO@yahoogroups.com, Craig Stevens
<craig.stevens@s...> wrote:

> Folks--
>
> What follows is a question regarding a limit switch problem on a

Fanuc

> 6M.
>
> Background:
> I have worked on many different types of film processing equipment

in my

> job at a major Connecticut newspaper. Several years ago I added CNC
> controls to a ShopTask mill/drill that uses Dan Mauch stepper

drives,

> and EMC.
>
> Question:
> My father recently purchased a Shizouka mill with Fanuc
> 6M control. He is chasing a problem with the -X, and -Y overtravel
> switches/electronics. He has been unable to get the machine to

clear

> the overtravel errors. The switches are OK as tested with a
> multimeter. He checked the + side of X, and Y to ground with a
> multimeter, and there is 24VDC at the switches, there is no voltage

on

> the - side of X and Y. He has gone through all the fuses, and all

are

> verified good with a resistance check. He has also verified wiring
> continuity is OK. Apparently the machine has a board in it with two
> rows of relays. There are two empty sockets on the board. He has

moved

> relays into the empty sockets to prove if the missing relays are

related

> to the problem, but the initial symptoms have not changed. Is there
> anyone on the list with experience with Fanuc controls that have

seen

> similar symptoms? Is there something common to the + axis on X,

and Y

> that he should be checking? I am thinking maybe an E-stop, or

interlock

> board...
>
> I have been trying to help him over the phone, but have not had a

whole

> lot of success because I have only seen the control in photos, and

my

> only CNC experience is with the old DeskNC, and EMC...
>
> You can look at my setup at: http://www.stevesys.no-ip.org/ There

is a

> photo of my setup on my Talon page, and a couple more on the spur

and

> christmas ornaments pages.
>
> I am grateful in advance for any assistance anyone can provide.
>
> --
> Craig Stevens <craig.stevens@s...>

I think that the relay for end travel would be held closed and fail
open. if the relay was bad, or the circuit to the relay was bad, it
would not work properly.

Since you said it was on both the -X and -Y I assume you mean that
the +X and +Y are working ? use those as the check against the
opposite circuit.

Dave