Plc; If Then Else Statement

HEY GUYS I KNOW IT'S SATURDAY MORNING BUT HERE IT GOES!!!! I HAVE A CONVEYOR ON IF I WHAT AN alarm to go off if the conveyor does not sense the car in it's tracks that is an if then else statement I am trying to add a timer I am using RSlogic or RSenglish I HAVE THE SOFTWARE SO THIS IS MY QUESTION CAN ANY OF YOU GENTLEMAN GIVE ME A LEAD AND CAN I COMBINE A GREATER THAN STATEMENT WITH A TIMER IF ON TON ?

Ever read the Iliad?

sorry you lost me their must be too early in the morning !!!!!!

Greetings richie,

In Ladder logic, Any "Rung" is already an "If Then Else" statement.(For digital outputs or memry bits)

Ex:

If Condition_A And Condition_B Then
Alarm = On
Else
Alarm = Off
End if

To do this with ladder:

Put your conditions as "contacts" and your result is the "coil".

 

Condition_A     Condition_B                 Alarm

---| |-------------| |-----------------------( )

Note: Condition can be any thing that is boolean (True or False, for example: a Timer done bit, A comparison result .. etc

Hope this helps

This is nice I like Greek methology hope I spelled it correctly but I need the conveyor to scan for an error I can think of a car as a trojan but I do not know if this will help maybe? but thanks anyway !!!!

Thanks you gave m an idea thanks again !!!!!

Richie,

Ayman Metwally's answer should steer you in the right direction.

Greg,

Personally, I would use Joyce's Ulysses as a standard of comparison when commenting on Richie's writing style rather than The Iliad.

Steve Bailey said:

...when commenting on Richie's writing style....

Click to expand...

Richie's writing style is fine - it's just that his PC has a terminal case of RCL (Random Caps Lock)

It also suffers from LOPS

Lack Of Punctuation Syndrome

Again if then else statement

Let me try be be clear I need an instruction that will detect any hangup in a conveyor and shut it down like something constantly scanning for an error and and finding error shuts it down.
again thanks guys!!!!

O.k. Guys Cute You Guys Have A Sense Of Humor Very Good

The problem is there are numerous ways to do what you ask AND they can vary from plc to plc.

This is one possible method:

      X                  Timer

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

|    10second             Error |

|----|=>|-----------------( )---|

If X is not present start timer
If timer is equal to or greater than 10 seconds latch bit
This bit can be used where needed to unlatch whatever

   Stop  Start    Error   ON

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

|       | ON   |

|       +-| |--+ 

richie said:

Let me try be be clear I need an instruction that will detect any hangup in a conveyor and shut it down like something constantly scanning for an error and and finding error shuts it down.

Click to expand...

You're not likely to find a single instruction that does exactly what you want to do. However, by using the instructions available to you, you can build the functionality you're looking for.

Greg Dake said:

Ever read the Iliad?

Click to expand...

sorry you lost me their must be too early in the morning !!!!!!

Click to expand...

It's the story of the Trojan Wars by Homer. So this Greek guy has a couple of Trojan princes for dinner, and one of them (Paris) dips the wife of the host (Helen). To add insult to injury, Paris then swipes Helen and takes her back to Troy. The Greek gets upset and rounds up his brother and all the other Greeks and goes to get her back. After years of attempting to take down Troy, the Greeks build a big wooden horse and leave it at the gates of Troy, and apparently go home in defeat. However a few Greeks are sweating it out inside the horse, and when the Trojans bring it inside the walls and party, the hidouts jump out and open the gates to let the other Greeks in and they all pillage and burn Troy.

Then comes the Oddesy. One of the Greeks proves to be a poor navagator, due to the fact that the Ageian Sea is not that big, and he totally gets lost and dreams up all kinds of excueses like a big one eyed monster, some woman with snakes for hair, some other girls that really can sing & seduace, bla bla bla, for taking like 10 years to sail what you or I could walk in a week.

All that said, I also fail to get the connection.....