Need Help!- Limit & Home switches

[Drools]

As I wait for my 80/20 to arrive I'm finishing off my electronics. The only piece I have left to figure out are the home and limit switches. So far all of my electronics have been working just fine connected directly to the lpt port however now I want to wire up some harnesses for the Limit and Home switches on the 3 axis.
One type has to be NC and the other NO, which is which? If I do not use a breakout board I'm assuming that I will have to use the status lines on the parallel poprt pins 10, 11, 12, 13, 15, x
Does anyone have a link to a schematic which does not use a breakout board for the home and limit switches?

Thanks

[LaserImage]

First, you don't necessarily need separate switches for home and limits. I have a total of three switches on my router and they function as both home and limits for all three axes. They are all wired in series and connected to one input on my G540. I happened to use hall effect switches but you can use whatever you want. The best part about he switches is that they are incredibly accurate and repeatable with more accuracy than my router can use.

Gary

[analogman]

If you use Mach3 you can set the home/limit switches for either NC or NO. The Mach3 video suggest using them NC so if a wire busts, it will stop the machine.

Like LaserImage says, Mach3 will support the limit switches being used as your home switches.

[Drools]

ok that is interesting, I will have to fire up the demo of Mach3 and give it a try. Another question is on the type & gage of wire used to go from the driver to motor. I was thinking high strand count silicone or rubber coated, 14 gage maybe?
What are others using?

[analogman]

I got my cables made up by Bob Campbell. 18AWG shielded 4 conductor. Alpha 2424C.

http://campbelldesigns.net/files/enc...e%20prices.pdf

[Senna]

Even though this thread seems to have run its course I'll attempt asking my question here rather than starting a completely new one.

I'm not at all well versed in electronics and I'm needing instruction as to how I wire these HE sensors to my C-10 BoB to use as Home & Limit switches. Obviously the power leg gets hooked to a +5 V Input terminal. Would the SIGNAL leg then go to any open INPUT terminal 10 thru 15...? Would the GND leg go to any GND terminal...? I'm aware the DRAIN needs to connect to chassis GND at the BoB end only...

I already have my Hall Effect sensors and NdFeB magnets and I wired them up using shielded 3 conductor 22 AWG cable. In testing off the machine I applied +5 V to the sensors and without the presence of the magnet the signal leg of the sensor reads zero volts. With the presence of the magnet the signal leg reads +5 V. So I'm assuming that this is the normal operation... but doesn't this make these sensors NO rather than NC that I'm needing...? If I break a wire then the magnet limits will not trigger a machine stop as the +5 V signal will never be sensed by the SIGNAL leg???

Any help would be appreciated...

Senna

[Jr's Farm]

Originally Posted by LaserImage First, you don't necessarily need separate switches for home and limits. I have a total of three switches on my router and they function as both home and limits for all three axes. They are all wired in series and connected to one input on my G540. I happened to use hall effect switches but you can use whatever you want. The best part about he switches is that they are incredibly accurate and repeatable with more accuracy than my router can use. Gary

Gary,

I'd be interested in a little more info on your setup if you don't mind.

- I'm curious about your repeatability with your Hall Effects switches.
- Have you noticed any ill effects due to temperature fluxuations?
- Are you getting your switch power from the G540 or your power supply?
- Pictures of your switch setup would be great, if you didn't mind

Regards,
Frank

[FandZ]

Of course it is better to use homing and limit switches but I'm not useing anything. I was useing them before but then I didn't bother to wire them back in when I redid my wiring. Once I upgrade to faster screws I think I will use them again though. At least homing switches and just use soft limits.