E-STOP Circuit - will this cause any problems?

[JAZZCNC]

Yes you are right it's not complete, I have assumed that K1 and K2 are the E Stop N/C contacts, no doubt birchy will be along shortly to clarify.

I didn't think anybody would be that Stupid Andy and also like GOBY presumed it incomplete.!! . . But suppose I should know better Esp after Seeing first hand the Strike time Bomb.!!

[Web Goblin]

I didn't think anybody would be that Stupid Andy and also like GOBY presumed it incomplete.!! . . But suppose I should know better Esp after Seeing first hand the Strike time Bomb.!!

I didnt think I had said anything that required being called "Goby" but never mind.

Birchy the estop input is not relying on the software to stop the machine but rather informing it that an estop has occurred but I think youve got that now.
I would still leave the pc on a seperate supply though but thats a personal opinion. I would not like a fault on the machine control side to trip the mcb and dump the pc at the same time.

[JAZZCNC]

I didnt think I had said anything that required being called "Goby" but never mind.

Didn't say anything wrong and No offence ment Mr was just being lazy.!!

[JAZZCNC]

Don't see any limit switch's. . . Are you not using them.?

If you do plan to use wire them in series with E-stop. Which then you'll need a limit override momentary button to back off.!

[birchy]

I would not like a fault on the machine control side to trip the mcb and dump the pc at the same time.

Fair point and easy to change.

Don't see any limit switch's. . . Are you not using them.?

Ermmmm...good question! I presume you mean limit switches to prevent the X, Y, Z from trying to drive beyond their physical stops? Although I've considered them, I was thinking that the stops can be set within the software, and if something went wrong, the drives would trip on overcurrent protection? Should limit switches REALLY be wired into the Safety Circuit? It seems wrong to me as they should be part of the machine functionality rather than an Emergency or Safety device?

[JAZZCNC]

Ermmmm...good question! I presume you mean limit switches to prevent the X, Y, Z from trying to drive beyond their physical stops? Although I've considered them, I was thinking that the stops can be set within the software, and if something went wrong, the drives would trip on overcurrent protection? Should limit switches REALLY be wired into the Safety Circuit? It seems wrong to me as they should be part of the machine functionality rather than an Emergency or Safety device?

Not wrong very correct and right.!! . . . They are safety limits so should be part of the E-stop system and again the software should just be informed not left in charge.!!

Edit:

The other beauty of running 24v thru limit switch's(And E-stop) is better noise immunity which can affect the standard 5V signal from Parallel port. The 5v signal is just used to inform software so the wire run is tiny just coming from BOB (+) input passing thru relay contact and back to (-) input so far less chance of picking up noise.!

[Web Goblin]

We have collision switches (proximity switches)mounted on our cnc machines at work at the cutting head and printer head mounts. These switches are connected to the emergency stop circuits to protect the machine and not the user.