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Old November 22nd, 2005, 12:50 PM   #1
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peng is offline
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Auto, Manual, Single cycle and single step

I am going to program a machine and have the following controls: Auto, Single Step, Single Cycle and Manual. My question is if I should make single step and single cycle sub-set of Auto. Meaning, You can only be able to do step and cycle, when you are in Auto and Manual is different animal it self.
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Old November 22nd, 2005, 01:09 PM   #2
Steve Bailey
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A lot depends on the nature of the controls, but my personal opinion is that 'Auto' is where you leave it when you walk away. If you have to be standing at the control panel to make something happen, then it isn't automatic. Based on that, I would make single step and single cycle a subset of manual.

This is really a judgement call on your part. Ten designers will come up with twelve different answers to your question.
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Old November 22nd, 2005, 01:23 PM   #3
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Good question. My customers are used to Single Cycle and Continuous Cycle being a mode of Auto and Single Step as a mode of Manual. YMMV.
"You can live to be a hundred if you give up all the things that make you want to live to be a hundred." Woody Allen
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Old November 22nd, 2005, 03:03 PM   #4
Steve Etter
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I agree. These would be better as subsets of Manual Mode rather than Auto Mode. Because neither Single-Step or Single-Cycle is much good without someone right there at the machine, it would be somewhat deceiving for these to be subsets for Auto.

You might want to consider a third alternative - Semi-Auto. These both strike me as modes that should really be in a group of their own. A three-position selector switch (either on an HMI or hardwired) would work well for this.

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Old November 22nd, 2005, 05:07 PM   #5
Eric Nelson
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I see 'single cycle' as very similar to 'semi-auto'. In injection molding, semi-auto would run a single cycle (or finish the current cycle) and stop. The next cycle was initiated by cycling the operator gate.

I have a single cycle mode on many of the machines I program.

Auto Cycle: Press 'Cycle Start' momentarily
Single Cycle: Press and hold 'Cycle Stop', then press 'Cycle Start' momentarily.

No extra buttons required.

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Old November 22nd, 2005, 05:23 PM   #6
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Like others have said, this is done many different ways. We have one machine with a "JOG" mode. If jog mode is selected, then auto mode and manual mode are disabled. In jog mode we can then "Home","Step" or "Single Cycle". Handy for de-bugging or testing adjustments that may or may not be the correct adjustment. Manual mode has some of these and some other stuff like changing material settings, counters and so forth.
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Old November 22nd, 2005, 07:00 PM   #7
Terry Woods
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AUTO is AUTO... MANUAL is MANUAL... "Never the twain shall meet!" (Eric Burdon and the Animals)

Single-Cycle is nothing more than a single, complete, iteration of an automatic-multi-cycle process.

Single-Step is nothing more than a single portion of a single cycle of an automatic-multi-cycle process.

Whether or not you can accomplish this depends on the basic design-philosophy in your program.

I recommend... highly modular, with extreme "Flag-Control".

To use "Flag-Control" means to control the initiation of a subsequent Module based on the conditions of the present Module.

The idea of Modularity and Flag-Control is a very involved concept... it takes a lot to explain it... but, once you see it, once you wear it... oh, man...
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Old November 23rd, 2005, 10:05 AM   #8
Sergei Troizky

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AUTO= Cycle starts, progresses and completes automatically.
SINGLE CYCLE= Same as AUTO less automatic cycle start. Cycle starts when a button is pressed.
STEP BY STEP= Same as SINGLE CYCLE, but cycle state (step) transitions occur only when a button is released and pressed again.
JOG= Same as STEP BY STEP, but motors move only when the button is pressed.

I use the same button for all of the above.
In AUTO mode it also alters the RUN/STOP of the machine.

Last edited by Sergei Troizky; November 23rd, 2005 at 10:08 AM.
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