Home Switch Setup Problem

TomS

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My home switch problem was tossed around a couple of months ago but I wasn't able to resolve the problem at that time but now it's come back full circle. I really need to figure out this out.

The problem is when homing the axis moves through the limit switch and keeps going. I've set my limit switches so I have room to react. I haven't crashed my mill ... yet! Under normal operation my limit switches work as they should. I want to be able to home my machine so that I can pick up where I left off without having to re-zero my setup.

Here are a few photos of my configuration.

9-6-2015-01.jpg
I ran the X the X and Y axis through their full travel in the plus direction and the Z axis in the minus direction tripping the limit switch. I set each axis DRO to zero and ran each in the opposite direction until the limit tripped. I noted the amount of travel for each axis and subtracted 1" for the X and Z axis and 1/2" for the Y axis. That's how I came up with the Soft Max settings in the picture below. When homed I want the table to be all the way to the left, saddle all the way forward, and the head at the top. 9-6-2015-05.jpg
I read on the Machsupport Forum that checking the "Home true when no home switches" might be the culprit. Unfortunately when I check the box the Apply button stays gray. I disabled the home switches but the Apply button is still gray. Not sure what's causing the Apply button to be inactive.
9-6-2015-04.jpg

Thanks,

Tom S
 
I dont know about your system, but. Have you went to the input screen and verified you are getting the input when the limit is made? You should also be able to "toggle" N.O. to N.C. or vise versa. Then try to home it. This will insure that the input is working in the software and you have the limit assigned to the correct axis and direction. I once had a problem on my plasma table because I assigned + instead of - on one of my axis. Hope this helps
Randy
 
I dont know about your system, but. Have you went to the input screen and verified you are getting the input when the limit is made? You should also be able to "toggle" N.O. to N.C. or vise versa. Then try to home it. This will insure that the input is working in the software and you have the limit assigned to the correct axis and direction. I once had a problem on my plasma table because I assigned + instead of - on one of my axis. Hope this helps
Randy

Thanks for your response. On the Diagnostics screen when manually actuating each limit switch the M1 thru M3 ++ and -- lights come on as well as the M1 thru M3 Home lights. This is telling me I have the switches wired correctly. It appears that Mach 3 is not recognizing the home switches but I don't know what else to check or change. I believe the reason I'm not able to save the Homed True When No Home Switches setting is because Mach recognizes that I have home switches set up. Maybe I need to reload Mach 3 but I'm not to that point yet.

Tom S
 
Got my homing switched to work, sort of. On the Program Run screen if I press the Ref All Home button the Z axis moves up and runs through the limit/home switch. Same as before. If I go to the Diagnostics screen and press the Zero All button nothings happens. None of the axis move. However, if I press the individual Ref X, Ref Y and Ref Z buttons each axis moves towards the home switch, stops, then moves off the switch a slight amount. This works the way it should. What baffles me is why the Ref All Home and the Zero All buttons don't work as they should.

I'm also getting a "Axis are not Refed to Normal Condition" in the Status bar after homing. What's causing this error message?

TIA

Tom S
 
Hi Tom,

Sounds totally frustrating!!!

May have covered this before but what are your switches?

Also in the general config page is the "Home SW. Safety" checked?

Jay
 
Last edited:
Hi Tom,

Sounds totally frustrating!!!

May have covered this before but what are your switches?

Also in the general config page is the "Home SW. Safety" checked?

Jay

My switches are from Automation Direct. The X and Y axis switches are lever type with a ball bearing roller. The Z axis is a plunger style with a ball bearing roller. All three are slow acting, IP67, with one NC and one NO circuit. Each switch is wired NC to an individual input on the breakout board. See the pictures below of my set up. Yes, the Home SW Safety box is checked. The switches work fine as limits and I can home the machine but with the limitations noted in my post above.

Tom S


20150319_135317.jpg

20150323_103336.jpg

20150323_103348.jpg
 
Throwing spitballs here...Have you tried the switches wired NO with the input pins set to active low?
 
Throwing spitballs here...Have you tried the switches wired NO with the input pins set to active low?

Haven't tried that. It would require a lot of rewiring as all my connections are soldered and shrink wrapped.

Should I reload Mach 3? The machine will home the problem being the Ref All Home button and Zero All buttons aren't functioning as they should. I've read on the Machsupport forum where you can get into the inner workings of Mach 3 and reprogram button functions. Not sure how to do that and wouldn't know what to change if I could.

BTW - got my flood coolant system working yesterday using a small pond pump. I have a larger coolant pump on order that will put out about 35 psi. Got to fix a couple of small enclosure leaks first.

Tom S
 
If you can try temporarily rewiring one axis i would try it before trying to dig into the inner workings. You can save your xml file and try reloading m3. Also could try installing a previous version.

Sent from my SAMSUNG-SM-G900A using Tapatalk
 
If you can try temporarily rewiring one axis i would try it before trying to dig into the inner workings. You can save your xml file and try reloading m3. Also could try installing a previous version.

Sent from my SAMSUNG-SM-G900A using Tapatalk

I'm going to reload Mach 3 current version as a first try. If that doesn't work I'll try an earlier version. I'll let you know how it works out.

Tom S
 
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