NEw to Forum and PLC's (Off Delay)

[goldprospector]

Hello everyone, I am 39 years old and my work is sending me to school to get and Associates in Applied Electrical Technologies. I am in my 3rd semester and just now starting in “Introduction to PLC’s”. We are training on the AB SLC 150 (yes, obsolete), and I have a pretty good handle on it.

One problem is that this is a “hands on” class but I would also like to work on this at home. I have a “Free Download” called TriLogi that has a built in simulator, but it does not have an OFF DELAY Timer.

Is there a way to “simulate” an OFF DELAY? OR does anyone know of an easy to use FREE PLC Program that I can get that has an OFF DELAY?



The Project is:

#1. “ Start 2 motors simultaneously with a single Start/Stop Station.”

#2. “Pressing Stop or Tripping OL relay of motor #1 will stop that motor only, and 4 seconds later, motor 2 will stop automatically.”

#3. “ Tripping the OL relay on motor #2 will stop both motors immediately”

#4. “ Do not series OL relay contacts.”



Here is what I have: (The instructor requires all timers have a reset)


start stop OL1 motor1
-------| |------|\|--------|\|---------(m1)-- line1
|
m2 |
------| |---

m1 OL2 o/d 4sec
-----| |----------|\|-----------{RTF}------ line2

o/d NOTO motor2
-----| |---------------------(m2)--------- line3

m2 o/d rac=0
---------| |-----------------[RST]-------- line4

 

[goldprospector]

cant figure out how to put spaces in between the words start, stop, OL1, Motor1, ect.

I typed it that way...but when the thread came up, they were all bunched together.
My apologies.

 

[504bloke]

Here is an excellent post from Tom Jenkins to simulate an OFF DELAY TIMER for an AD plc that hasnt got one

http://www.plctalk.net/qanda/showpost.php?p=3427&postcount=5

Here is a link for Step 7 lite software (for Siemens s7-300) also this processor has an off delay timer, the s7-300 is mid range plc from the brick type (micrologix, S7-200, FX0S) plc's.

https://support.automation.siemens.com/WW/llisapi.dll?func=cslib.csinfo&objId=22764522&objAction=csOpen&lang=en&siteid=cseus&aktprim=0&extranet=standard

 

[Terry Woods]

In a word processor, such as Word, type in your code, in COURIER, as follows...

[ladder]

Enter your code here...

[/ladder]

Then, select the text, including the "[ladder]" and "[/ladder]" stuff, and cut-n-paste your code from the Word Processor to the Post Window.

Having done so, your code will NOT appear as you typed it.

Then, PREVIEW your Post!

The code WILL appear as you typed it!

If you see errors, fix them in the word-processor version then cut-n-paste again. (Unless you see that particular characters are off by only one or two places, then you can fix it on the post window.)

Regarding Off-Delay... you don't need a specific Off-Delay Timer at all to accomplish an Off-Delay.

You can simply use a normal On-Delay Timer to control a Stop or Off bit in a latched ON circuit.

If you think about it, in human terms, an Off-Delay action is really a function of an On-Delay!

 

[goldprospector]

In a word processor, such as Word, type in your code, in COURIER, as follows...

[ladder]

Enter your code here...

[/ladder]

Then, select the text, including the "[ladder]" and "[/ladder]" stuff, and cut-n-paste your code from the Word Processor to the Post Window.

Having done so, your code will NOT appear as you typed it.

Then, PREVIEW your Post!

The code WILL appear as you typed it!

If you see errors, fix them in the word-processor version then cut-n-paste again. (Unless you see that particular characters are off by only one or two places, then you can fix it on the post window.)

Actually, this is the way that I typed the post...I used MS Word...Then copied and pasted, when I previewed...It was correct, but when the actual thread was started...then that other came up...maybe I will get the hang of it.

 

[Terry Woods]

I doubt it.

If you did what I said... there would be... NO PROBLEMO!

You did something wrong (in terms of my instructions)... no doubt about it.

Did you use COURIER?

 

[goldprospector]

As per your instructions...probably not...but as far as word processor...yes...now as far as courier...probably not...used whatever came up as standard in MS Word, probably Times New Roman. I will do better next time, again, my apologies.

 

[goldprospector]

Here is an excellent post from Tom Jenkins to simulate an OFF DELAY TIMER for an AD plc that hasnt got one

http://www.plctalk.net/qanda/showpost.php?p=3427&postcount=5

The only way that I can get the timer to work correctly with the stop button is to hold the stop in the open position for the elaped time period. It works like this...but just tapping the stop did not work...although, programming on the SLC 150, the same sim would work due to using an OFF DELAY (as per instructors request).

As far as the Program...Step 7 Lite...That is a complicated rascal. I tried doing a couple of things with it and it told me that it could not communicat with my computer...I will need some time to figure that one out.

 

[elevmike]

 

      start    stop        OL1         motor1

-------| |------|\|--------|\|---------(m1)-- line1

            |

      m2    |

------| |---



      m1          OL2          o/d 4sec

-----| |----------|\|-----------{RTF}------ line2



     o/d                  NOTO motor2

-----| |---------------------(m2)--------- line3



          m2                 o/d rac=0

---------| |-----------------[RST]-------- line4