PLC and moving a Ram between two limit switches, and back via momentary switch.
PLC and moving a Ram between two limit switches, and back via momentary switch.
(OP)
I've got the ram moving forward to limit switch (based on physical user switch), then when switch is reversed, ram goes back to starting limit switch, as long as user holds in the switch.
[ ]-[/]-( ) Easy
I'd like to automate this so a momentary switch makes it latch, drive to limit, pause, then fire the other valve to bring it back to limit switch and stop.
I've seen how to latch
[S]--------------[/Limit]--------------------(O)
| |
--[O]---------
I've been programming C/C++/C#/Pascal/ASM for ages, and I'm just trying to help some friends that have a dead machine. I went with the Click PLC, for cost. I've never done PLC, but have done quite a bit of micro controller work.
//Example if you wanted to scribble, or just plain comment about it is fine. I'm new to this.
X0 out limit
X1 in limit
X2 momentary user button
y0 Ram out
y1 Ram in
If anyone could explain the normal way this is done, I'd appreciate it.
I was thinking of just using a memory bit for each stage, switch sets bit (and master busy bit). Bit drives forward until limit, clears bit and sets new bit.
New bit triggers the reverse function to limit then clears bit and master busy bit.
Or is this typically done using a load of Or Not And logic only?
This is only the tip of the iceberg in this project, but if I can get some standard practices for readability, the rest is just more of the same.
Thanks
Charles
[ ]-[/]-( ) Easy
I'd like to automate this so a momentary switch makes it latch, drive to limit, pause, then fire the other valve to bring it back to limit switch and stop.
I've seen how to latch
[S]--------------[/Limit]--------------------(O)
| |
--[O]---------
I've been programming C/C++/C#/Pascal/ASM for ages, and I'm just trying to help some friends that have a dead machine. I went with the Click PLC, for cost. I've never done PLC, but have done quite a bit of micro controller work.
//Example if you wanted to scribble, or just plain comment about it is fine. I'm new to this.
X0 out limit
X1 in limit
X2 momentary user button
y0 Ram out
y1 Ram in
If anyone could explain the normal way this is done, I'd appreciate it.
I was thinking of just using a memory bit for each stage, switch sets bit (and master busy bit). Bit drives forward until limit, clears bit and sets new bit.
New bit triggers the reverse function to limit then clears bit and master busy bit.
Or is this typically done using a load of Or Not And logic only?
This is only the tip of the iceberg in this project, but if I can get some standard practices for readability, the rest is just more of the same.
Thanks
Charles





RE: PLC and moving a Ram between two limit switches, and back via momentary switch.
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RE: PLC and moving a Ram between two limit switches, and back via momentary switch.
Has nice simple example programs showing logic control, flow for simple tasks.
Thanks a bunch,
Charles
RE: PLC and moving a Ram between two limit switches, and back via momentary switch.
SW = Control Panel SW
O = Physical Coil/actual output.
I forgot to clear run, but does this seem logical? (unit is in the mail to me now, can't test)
Is this the general pattern for such a thing? Does have an error (like it will cycle over and over right now)....
RE: PLC and moving a Ram between two limit switches, and back via momentary switch.
Also you cant have multiple output states for Accumulation Forward or back. What is going to happen is the PLC will just execute the last output of this Forward or Back. As it goes thru the logic.
Most PLCs do this
Looks at INputs
executes logic
sets outputs
repeat cycle
RE: PLC and moving a Ram between two limit switches, and back via momentary switch.
Set (forward, back), then just clear each bit as the task is completed?
RE: PLC and moving a Ram between two limit switches, and back via momentary switch.
RE: PLC and moving a Ram between two limit switches, and back via momentary switch.
Thanks for the tips/heads up/help.
I'll update post at the end of project with results/pics. This machine is over 100' long, 60' wide and 25' tall.
RE: PLC and moving a Ram between two limit switches, and back via momentary switch.
https://drive.google.com/file/d/0B882DaQ0eI-vTjN3e...
100' long is correct, maybe only 25' wide. Definitely 25' tall. I didn't measure because it's irrelevant.
RE: PLC and moving a Ram between two limit switches, and back via momentary switch.
RE: PLC and moving a Ram between two limit switches, and back via momentary switch.