Bridgeport Series II Interact 2 EMC retrofit -- limit switches

[ichudov]

Bridgeport Interact 2-How do I wire limit switches 0 Minutes ago Karma: 0
I have a Bridgeport Series II Interact 2:

igor.chudov.com/projects/Bridgeport-Seri...Interact-2-CNC-Mill/

I am converting it to use with EMC. I already have a PC with EMC installed.

It has FIVE (sic) limit switches: two on X and Z, and one on Y. The limit switch on Y is triggered by overtravel in either direction.

The switches are normally closed.

I use PPMC by Pico systems.

My question is, how should I wire the limit switches to facilitate homing the mill, etc?

Can I just use them as inputs to the PPMC controller and let EMC take care of it?

What is the "canonical way" or treating limit switches?

Looking to get some wisdom here.

Thanks

[Karl_T]

Hi Iggy,

i got no help for you, just welcome to the zone.


Check out the Camsoft forum if you want to see where i hang out.

Karl

[TarHeelTom]

When you say EMC, I assume you're using a PC to run EMC.

On my Bp, all the limit switches are wired in series. One of the limitations in dealing with a PC to run EMC is the number of input pins. When all the limit switches are wired in series, you can hook them all to a single input pin. You could do the same with your homing switches, but if they are reached before the limit switches are reached, it's easy for EMC to get confused.

One possible way to deal with this is to just put a manual switch in parallel with the homing switches, and close it after you finish homing. Another way is to simply put the homing switch just past the limit switch, and tell EMC to "ignore" the limit switch during the homing process.

There is a section in the .ini files and .hal files where you tell EMC how you want to go about the homing process.

I have no idea what the "canonical way" of treating limit switch is. I do know that you always want to use normally closed switches for homing switches. If you use normally open switches, and a wire or terminal comes loose, you'll only find out about it after the crash.

I'm not conversant with that particular board, but if you have any serious issues, just call or email Arturo and ask for help.

Tom