Sub routines are sub programs in a PLC project. We can split the whole program by its function or sequence. We can call the sub programs from main page using instructions.
In the above picture, there are totally 8 files listed. In that SYS 0 and SYS 1 are default files.
We can use this instruction using condition by adding some input before the instruction like,
In the SBR File number, we should give the ladder number i.e. which sub routine we should call at this place as shown in below figure.
Return instruction should add at the end of the sub routine program.
In this program, Sub routine instructions are explained using simple example.
Note: Since its for example, LAD 4, LAD 5,LAD 6,LAD 7 pages are not included in this program
If Sw2 is not turned on, In LAD 3-IO Mapping, no operations will be happen.
Even though, sw6 is turned ON, Move block is not doing any operation because in main page, JSR instruction is not activated
If Sw2 is turned on, In LAD 3-IO Mapping, operations will be happen.
sw6 is turned ON, Move block is doing it s operation because in main page, JSR instruction is activated
The above explained concept for subroutine is for example only. We can use this example program to understand the working of JSR and RET function in AB PLC ladder logic programming.
If you liked this article, then please subscribe to our YouTube Channel for PLC and SCADA video tutorials.
You can also follow us on Facebook and Twitter to receive daily updates.
Read Next:
PLC Training Software Download
Allen Bradley Interview Questions
The conveyor sorting machine is widely used in the packing industries using the PLC program…
Learn the example of flip-flop PLC program for lamps application using the ladder logic to…
In this article, you will learn the STAR DELTA programming using PLC controller to start…
Lube oil consoles of rotary equipment packages in industrial process plants are usually equipped with…
Rotating equipment packages such as pumps, compressors, turbines need the lube oil consoles for their…
This article explains how to blink lights in ladder logic with a detailed explanation video…