Estop & Limit Switch Setup?

[Regnar]

Is this the way that I hook up an estop and limit switches. I added more switches to the estop so that I could fine tune each axis during set up. I have read and looked here and on the yahoo groups and it just keeps getting more and more confusing. So if you guys can help me and let me know that would be great. I also know that it is not isolated and that I could fry my computer but Its almost time for a new one.

[pminmo]

As wired, you have no issues with isolation. Just don't wire any of those points to anywhere else.

[Regnar]

Thanks Pminpo, I was just wonder about the way everything is hooked up. Also could I use 1 10 ohm resistor and fork it out to the 3 pins or do I need 3 10 ohm resistors for each axis.

Last but not least once I have everything hooked up I would then make ports 10,12, 13 actively low because it is going straight to ground. But once one of the switches is opened or a wire breaks the system would then go actively high because it is then trying to ground threw the printer port where mach3 would get the signal to stop???????????

I am horrible at electronics I couldnt believe that I didnt smoke my board, but I wont lie I read the instructions 10 times before even unwrapping the board and I also did each item one at a time checking off the sheet to make sure I didnt skip or miss a step. Just now trying to take it a step further with limits and estops.

[pminmo]

Regnar,
You need seperate resistors and they need to be more on the order of 1000 ohms. Your PC may already have pullups and don't need an external resistor. Actually the pin will be active high with NC switches. Normal will be low inputs, limit will be high when the switch opens. i.e. Limit = active = high

[Regnar]

Thanks Again, now its time to finish building

[boguski.1]

Regnar,

I have a 3-axis Xylotex kit with 425oz-in steppers. I've just recently completed my electronics with good results! (My background is mainly mechanical and I know what you're going through!)

I am attaching diagrams detailing my circuits, including a spindle control circuit. I'm also attaching my wiring diagram and a detailed view of the breakout boards I wired up using radioshack solder boards and terminals. My original sketches of the limit circuits looked exactly like your first post, and I wanted to find a way to clean up the wires and protect the resistors. Components were fairly inexpensive (although the shack can get pricey, sometimes catalogs and wholesalers are much better) and if you've soldered before they should be a piece of cake.

I see in your diagram what appears to be separate pins for each individual axis limit set? I wired all my limit switches to one pin in series (including my e-stops) so that a limit fault on any axis or e-stop button push will trip the system. I have a separate pin wired for each axis' home switch. My axis enable switches are identical to yours minus the e-stop. Just curious what setup you plan to use.

Hope this is helpful! The best advice in regards to not blowing up the board is to use the heck out of your multimeter! I know I have


Brian

PS: Anyone viewing these documents remember: mechanical guy here, use at own risk, suggestions welcome!!!

[Regnar]

boguski, Thankyou for your drawings and for your time in this post. I have the plan of doing each of the axis sepratly because it only uses up 3 pins. I intend to use the home and limit switches as the same. I couldnt really tell for sure with you second drawing but it looks to me that you use 5 pins for your limit and home switches. I never thought of using a e-stop with the limit switches but I might make it a stop button. I like the thought of a limit switch not be associated with the software that could be the problem in the first place.

Using a multi meter probably saved me so far, but I had to read the instructions to figure out how to use it.

[boguski.1]

Gotcha, I forgot that mach could use limits as home switches as well! My setup uses 4 pins, 1 for all limits and e-stops, and three for homes. There are 5 resistors shown in the diagram because the fifth is an extra in case I need to add something in the future. Looks good, best of luck with your testing!

[Komissar]

Hi All, I have the Xylotex 3-axis with 425oz steppers also. Bogusi.1, thanks for sharing your wiring diagrams, I've decided to use your layout. I have a question though, would it be possible to add LEDs, so you would know which limit has been tripped? I thought red for limits & E-stop and green for home. But I'm not quite sure how to add that function in. Does anyone have any thoughts or possible schematic they can share? Thanks again.

Komissar

[Al_The_Man]

Is this the way that I hook up an estop and limit switches..

The logic looks wrong to me for E-stop and limit switches, for that to work you would either need all three limits switches NC in series with the NC Estop (AND'd), Otherwise with three in parallel N.O. The E-stop is not going to do anything.
If limits N.O. then the Estop should be in parallel also (OR'd).
Al.

[boguski.1]

Wow I completely missed that! Al's absolutely right Regnar, your limits should all be in series normally closed if using one pin for limits. However, it appears that you are using a separate pin for your x, y, and z limits? If that is the case, I think the circuit will work. If one limit switch is tripped, say an x limit, the x assigned pin will read "high" since the +5V goes directly to the pin instead of to ground. Then one of the switches on each circuit could be assigned in Mach to act as a home switch as well. Al I may be interpreting this wrong!

Komissar, to answer your question I believe it is only possible in my setup to know if the trip is either a limit trip or a home trip, since all of my limits are on one circuit and each home switch has its own circuit. I suppose you could have the following:

X Home Green Light
Y Home Green Light
Z Home Green Light

Limit Trip Red Light

As far as actually wiring these lights in, this exceeds my electrical knowledge! I don't think there is any way in a series circuit to know which limit trips individually, but maybe an electrical guy has a solution for that. I'm curious to know too!

[Al_The_Man]

I was refering to the ENA switches, If they are normally open as shown, the E-stop will have to be NC for them to work, however, if operating the E-stop alone with the switches N.O. nothing is going to happen.
The E_stop should be in parallel with the switches but N.O.
Al.