CAD CAM EDM DRO - Yahoo Group Archive

Re: Router spindle electrical noise.

Posted by balsaman_cnc
on 2003-10-21 09:35:02 UTC
It's a big job to replace the cables, if there is an easier solution,
I will try those first.

The limits (there are actually 6) are run back to the controller in
sets of two (2, z axis in series, 2, x axis in series, and 2, y axis
in series). At the controller these 3 sets are connected in series.
I will add the resistor as you suggest. A small cap will also be
added at the breakout board, from limits to ground.

Eric


--- In CAD_CAM_EDM_DRO@yahoogroups.com, Dan Peirce <danpeirce@t...>
wrote:
> It appears there has been a consensus that this problem would be
fixed with
> shielded cable. It has worked for others.
>
> I would like to suggest a cheaper easier solution but I don't have
the CNC
> machine to test it on so I cannot guarantee it will work for you.
>
> First I am concerned with how you ran the wires to the three
switches.
> Schematics don't show such things. I would wire a twisted pair from
the
> control box to each of the three switches. In that case any noise
linking
> into one conductor would also link the paired one in almost exactly
the same
> way. The noise would therefore tend to cancel itself by the time it
was
> conducted back to the control box.
>
> My second suggestion would be to add a 50 ohm 1 W resistor from the
switched
> line to ground before the 4.7kohm resistor. The effect would be to
lower the
> impedance to ground and dampen induced noise. It will pull an extra
100 mA
> from the supply which I would expect could handle it.
>
> More effective still would be to use a optocoupler like the 4n25.
>
> By the way, the LED's are shown backwards in your schematic.
>
> On October 20, 2003 03:59 pm, you wrote:
> > Wow what a great response! I think I will try the easy stuff
first
> > so I will put a wee cap on the limit switch input to the breakout
> > board err/res manager.
> >
> > My breakout board is home made. See the circuit here:
> >
> > http://www.e-zflight.com/files/ncnczy.jpg
> >
> > gecko faults and the limits trigger the same input to pc, but the
> > gecko's are fine. External LED's indicate gecko status. There
are
> > actually 4 gecko's used, drawing shows two.
> >
> > Eric
> >
> >
> >
> > --- In CAD_CAM_EDM_DRO@yahoogroups.com, "balsaman_cnc"
> >
> > <balsaman_cnc@y...> wrote:
> > > The electrical noise generated by my Porter cable Router is
> > > triggering my limit switch circuit. The limits are high and go
low
> > > if there is a problem. They are all in series (NC). If I set
the
> > > speed on my router down 20% or so the problem goes away. I slid
> >
> > one
> >
> > > of those ferrite donuts over the limit switch cable with no
> >
> > effect.
> >
> > > Is there something else I can try? I used shielded cable on all
> > > cabling EXCEPT the limit switches...do I need to replace all
that
> > > cable? Are there other options?
> > >
> > > Thanks for any help you can provide.
> > >
> > > Eric
> >

Discussion Thread

balsaman_cnc 2003-10-19 09:26:33 UTC Router spindle electrical noise. Lee Studley 2003-10-19 13:32:37 UTC Re: Router spindle electrical noise. Dan 2003-10-19 17:03:56 UTC Re: [CAD_CAM_EDM_DRO] Router spindle electrical noise. John Johnson 2003-10-19 17:04:48 UTC Re: [CAD_CAM_EDM_DRO] Router spindle electrical noise. Jon Elson 2003-10-19 22:12:44 UTC Re: [CAD_CAM_EDM_DRO] Router spindle electrical noise. Superonline 2003-10-20 07:53:46 UTC Re: [CAD_CAM_EDM_DRO] Router spindle electrical noise. Carl Mikkelsen 2003-10-20 08:57:13 UTC Re: [CAD_CAM_EDM_DRO] Router spindle electrical noise. cncman172 2003-10-20 09:27:16 UTC Re: Router spindle electrical noise. cnc002@a... 2003-10-20 11:00:26 UTC Re: [CAD_CAM_EDM_DRO] Re: Router spindle electrical noise. c_holm10017 2003-10-20 14:26:47 UTC RF Shielding - was Re: Router spindle electrical noise. Paul 2003-10-20 15:22:02 UTC Re: [CAD_CAM_EDM_DRO] RF Shielding - was Re: Router spindle electrical noise. balsaman_cnc 2003-10-20 20:42:26 UTC Re: Router spindle electrical noise. jimalb2309 2003-10-20 20:42:47 UTC RF Shielding - was Re: Router spindle electrical noise. Chris Cowley 2003-10-21 07:40:25 UTC Re: [CAD_CAM_EDM_DRO] RF Shielding - was Re: Router spindle electrical noise. Dan Peirce 2003-10-21 07:41:58 UTC Re: [CAD_CAM_EDM_DRO] Re: Router spindle electrical noise. balsaman_cnc 2003-10-21 09:35:02 UTC Re: Router spindle electrical noise. balsaman_cnc 2003-10-22 08:16:28 UTC Re: Router spindle electrical noise. SOLVED