Need help to write a PLC code using Melsoft GX Developer

[KnowPuzzles1]

My design got wiped away. Hold on.

 

[KnowPuzzles1]

Ok, here's what I came up with....

|----[nc-inx2]----[nc-inx3]----[no-inx1]--------[outy1]--------|

|----[nc-inx1]----[nc-inx3]----[no-inx2]--------[outy2]--------|

|----[nc-inx1]----[nc-inx2]----[no-inx3]--------[outy3]--------|

|----[no-inx1]----[no-inx2]----[no-inx3]----[nc-outy5]----[timer1]----[outy4]----|

|--------------------------------[no-outy4]--------[timer2]--------[outy5]-----------|

 

[KnowPuzzles1]

By the way...
//// no is normally open
//// nc is normally closed
//// timer1 activates outy4 as alarm light on for 1 sec.
//// timer2 activates outy5 as alarm light off for 1 sec.

 

[osmanmom]

123

 

[Lancie1]

You solution looks satisfactory, Sumom. You should add address descriptions for your Pushbuttons and your Lamps. Relays M0, M1, and M2 are not needed in this problem to make the logic work, but many programmers prefer that method as a personal style.

KnowPuzzles1, your solution is deficient. It works for Steps 1, 2, and 3, but not for Steps 4, 5, 6, and 7. You have part of Step 7, but you failed to add your Timer 1 NC contact to your rungs 1, 2, and 3, and failed to make your flashing function control Lamps 1, 2, and 3 (as required in the original problem statement). Possibly if you had read the problem, and then labeled your addresses, you would have realized that there were missing parts in your logic.

 

[KnowPuzzles1]

I figured that step 7 got me baffled, but I know I can do/re-do the rungs for steps 4, 5, & 6. Shall I try again?

Hello Osmanmom, how did you make such a fancy pic?

 

[Lancie1]

Sure, have another go at it. I will be glad to check your work!

 

[KnowPuzzles1]

|------[no-inx1]--------------.---------[outy1]--------|
|
|
|---[no-inx2]---[no-inx3]---|

|-------[no-inx2]-------------.--------[outy2]--------|
|
|---[no-inx3]---[no-inx1]---|

|-------[no-inx3]-------------.--------[outy3]--------|
|
|
|---[no-inx1]---[no-inx2]----|


(Working on step 7 now.)

 

[KnowPuzzles1]

|----[no-inx1]----[no-inx2]----[no-inx3]----[nc-light-off]----[timer1s]---(out-light-on)----|

|----[no-light-on]--------.----[outy1]-----------------------------------------------------------|
|
-----[outy2]-----------------------------------------------------------|
|
-----[outy3]-----------------------------------------------------------|

|----[no-light-on]------------------------[timer1s]---------------(out-light-off)---------------|

(The other part finally done.)

 

[Lancie1]

KnowPuzzles1,
You have some of your Input numbers mixed up. But here is your logic inserted into the LogixPro Simulator (as best I can interpret it). You can see in the attached picture that with all 3 Inputs ON, your timer will not flash the bits, because they are already held ON by the top branch of each rung.

What you need on the top branch of each Output rung are 2 bits to keep the single input from acting UNLESS the other 2 bits are OFF. For example, on Rung 1 top branch, you need this:

 

|  In X1   In X2   In X3    Out Y1  |

|---| |-----|/|-----|/|---+---( )---|

|                         |         |

|  In X2   In X3   In X1  |         |

|---| |-----| |-----|/|---+         |

|                         |         |

| light-on                |         |

|---| |-------------------+         |

For the same error on the 2nd parallel branch, you need to inhibit the branch when all 3 inputs are on (so that the 3rd branch can cause the flashing action. Right now with your logic, the 1st and 2nd branches keep all Outputs ON all the time. These 2 errors are present for all 3 Output rungs.

Note that you should not use each Output coil ---( )--- more than 1 time. The 2nd use will cause an error in your program. Because it is a scanned program from top to bottom, only the last case of an Output will work correctly, nullifying all previous cases.

 

[KnowPuzzles1]

Hi Lance,
I should have named my outputs forced the lights properly....
I like to have my program neatly made like the image you showed me.
I do not like how the quick reply box re-arranged my LD.
I think that is why you were not place with what I made.
Speaking of the image, I made close to what you created.
Anyhow, I am eager to learn more & do more. Do you have other problems to give?
Do you have any lessons that you know that Ron Beaufort gives that he want all PLC students to know.
Yes, I still like to learn more. Thanks.

 

[Lancie1]

I do not like how the quick reply box re-arranged my LD.

The next time, click the "Go Advanced" button, then use the Ladder Quotes around your ladder to preserve the format.

I think that is why you were not place with what I made.

It could be too that what you made had many errors. Think about that and investigate.

Do you have other problems to give?

Sure, I have collected lots of student-type PLC problems. What degree of complexity do you want? Which brand and model of PLC do you want?

Attached is a good beginner-type problem using the Siemens-type X inputs and Y outputs, a classic.

 

[KnowPuzzles1]

I'm interested in the Schneider Electric, Siemens, G&E's, & Allen-Bradley Brands.
I have not decided what model of each brand. Uuuuumm, Modicon is a model of Schneider, right?

 

[danatomega]

Google can usually help you out for such questions...

http://www.schneider-electric.com/p...ther-controllers/3950-pacs/1468-modicon-m340/

 

[ngoclan]

I need to do some research on Mitsubishi PLC program. I want to download original program (made by someone else, I have no source code) and save on PC (with GX developer) from PLC, play a little with its copy (on PLC) and then upload original program to PLC. Is it safe ? Will PLC work as before manipulating program ? Are there any traps ? Is you can guess I'm starting my adventure with this technology