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Jones - (2 posts) Mar-17-01, 07:02 PM (EST)

"Using another instruction for a program with the RSLogix 500"

I wrote a program that deals with programming a wash cycle to do a load of clothes. I used a Timer On delay to count the minutes for each cycle, with a Count up Counter to keep track of the current minute and a Reset to reset the timer after one minute.
I used the GEQ and LES instructions to turn on the hot value, cold value, motor, and pump for each cycle. I need to know what other instructions besides the GEQ and LES instructions, that I can use to turn on these outputs.
Input - start, stop
Output- hot water value, cold water value, pump, motor
All outputs shut off after cycle
Wash Cycle 2 min - hot and Cold water turns on
16 min - hot and cold water turns off and motor turns on
2 min - motor turns off pump turns on
Rinse Cycle 2 min - pump turns off cold water turns on
3 min - cold turns off, motor turns on
Spin Cycle 2 min - motor turns off pump turns on
3 min - pump turns off, motor turns on
After 3 min motor turns off and cycle starts over again when start turns on
This is how I set my GEQ and LES instructions
Hot water GEQ = 0 LES = 2 min
Cold water (in parallel) - GEQ = 0 min, LES = 2 min
GEQ = 20 min, LES = 22 min
Motor (in parallel) - GEQ = 2 min, LES = 18 min
GEQ = 22 min, LES = 25 min
GEQ = 27 min, LES = 30 min
Pump (in parallel) - GEQ = 18 min, LES = 20 min
GEQ = 25 min, LES = 27 min
If you could give me information how to use another instruction for this program I would appreicate it
Thank you

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RE: Using another instruction for a..., John Lowen, Mar-19-01, (1)
RE: Using another instruction for a..., Tom Jenkins, Mar-19-01, (2)

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John Lowen - (36 posts) Mar-19-01, 02:50 AM (EST)

1. "RE: Using another instruction for a program with the RSLogix 500"

This is what I could make of your
Project description!
* Input - start, stop
* Output- hot water valve, cold water valve, pump, motor
* All outputs shut off after cycle
* No feedbacks
* Use only one timer
If you are using only one timer
and you have a sequential flow
to describe your program. You
may present it this way.

Start
|
Timer start,while Timer.ACC<2minutes, cold watervalve
and hot water valve is open,pump is off, motor is off, etc.
|
...
|
...
|
END

If you have a problem with GEQ and LES
try using OSR,OTL,OTU in conjunction with
these "Events"

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Tom Jenkins - (768 posts) Mar-19-01, 10:06 AM (EST)

2. "RE: Using another instruction for a program with the RSLogix 500"

It may actually be simpler to use multiple timers. I would suggest you divide the operation into separate cycles - cold water fill, hot water fill, wash, rinse, ..... Use a coil as a "flag" to indicate the active cycle, one coil for each step. Use a timer for each cycle, and when it "times out" set a coil as a "flag" to indicate the cycle is completed. This same flag can then trip the active coil for the next cycle, which will operate the timer for this next cycle. This looks like more code, but it is actually easier to understand and trouble shoot. You can immediately see which cycle is active, and use the active bit (flag) to turn on the appropriate outputs for each cycle.
If you want to stick with one timer, consider using your greater than or equal statements to set a coil to indicate which step is active.
Make sure you use clear names for the nickname of each step - don't use step 1, for ecample, use "Cold Water Rinse". This simplifies troubleshooting.

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Jones - (2 posts)	Mar-17-01, 07:02 PM (EST)
"Using another instruction for a program with the RSLogix 500"
I wrote a program that deals with programming a wash cycle to do a load of clothes. I used a Timer On delay to count the minutes for each cycle, with a Count up Counter to keep track of the current minute and a Reset to reset the timer after one minute. I used the GEQ and LES instructions to turn on the hot value, cold value, motor, and pump for each cycle. I need to know what other instructions besides the GEQ and LES instructions, that I can use to turn on these outputs. Input - start, stop Output- hot water value, cold water value, pump, motor All outputs shut off after cycle Wash Cycle 2 min - hot and Cold water turns on 16 min - hot and cold water turns off and motor turns on 2 min - motor turns off pump turns on Rinse Cycle 2 min - pump turns off cold water turns on 3 min - cold turns off, motor turns on Spin Cycle 2 min - motor turns off pump turns on 3 min - pump turns off, motor turns on After 3 min motor turns off and cycle starts over again when start turns on This is how I set my GEQ and LES instructions Hot water GEQ = 0 LES = 2 min Cold water (in parallel) - GEQ = 0 min, LES = 2 min GEQ = 20 min, LES = 22 min Motor (in parallel) - GEQ = 2 min, LES = 18 min GEQ = 22 min, LES = 25 min GEQ = 27 min, LES = 30 min Pump (in parallel) - GEQ = 18 min, LES = 20 min GEQ = 25 min, LES = 27 min If you could give me information how to use another instruction for this program I would appreicate it Thank you
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John Lowen - (36 posts)	Mar-19-01, 02:50 AM (EST)
1. "RE: Using another instruction for a program with the RSLogix 500"
This is what I could make of your Project description! * Input - start, stop * Output- hot water valve, cold water valve, pump, motor * All outputs shut off after cycle * No feedbacks * Use only one timer If you are using only one timer and you have a sequential flow to describe your program. You may present it this way. Start \| Timer start,while Timer.ACC<2minutes, cold watervalve and hot water valve is open,pump is off, motor is off, etc. \| ... \| ... \| END If you have a problem with GEQ and LES try using OSR,OTL,OTU in conjunction with these "Events"
	Top

Tom Jenkins - (768 posts)	Mar-19-01, 10:06 AM (EST)
2. "RE: Using another instruction for a program with the RSLogix 500"
It may actually be simpler to use multiple timers. I would suggest you divide the operation into separate cycles - cold water fill, hot water fill, wash, rinse, ..... Use a coil as a "flag" to indicate the active cycle, one coil for each step. Use a timer for each cycle, and when it "times out" set a coil as a "flag" to indicate the cycle is completed. This same flag can then trip the active coil for the next cycle, which will operate the timer for this next cycle. This looks like more code, but it is actually easier to understand and trouble shoot. You can immediately see which cycle is active, and use the active bit (flag) to turn on the appropriate outputs for each cycle. If you want to stick with one timer, consider using your greater than or equal statements to set a coil to indicate which step is active. Make sure you use clear names for the nickname of each step - don't use step 1, for ecample, use "Cold Water Rinse". This simplifies troubleshooting.
	Top

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