how to make three switchs sequence

hey guys, wondering if any one could help me with my plc, i need an idea how to make please! i would appreciate your help
A simple small moulding machine has three pneumatic linear actuators
1. Linear actuator opening and closing the mould
2. Linear actuator moving the barrel forward against the mould and
back away from the mould
3. Linear actuator moving forward injecting polymer and returning
(refilling for the next shot).
The process has the following constraints
When the mould is closed the barrel may move forward and back, when the barrel is forward the injector may be moved forward and back, the injector must be back before the barrel can move, the barrel must be back for the mould to open and close. When the mould is opened the part can be removed.
Both the time the mould is closed and the time injecting linear actuator is forward should be adjustable.

Certainly - post what work you have done so far. We will advise on anything else you should show. Note at what point you have difficulty.

At a minimum post the type of PLC and an I/O list.
State the exact sequence you will be implementing. You listed some restraints on movement but not the exact sequence for the whole procedure.

Welcome to the forum.

I am glad someone helping
Actually there are three cylinders the sequence is as follow:
cylinder 1 cylinder 2 cylinder 3
moving forward moving moving
stable stable injecting
stable stable retracting
retracting retracting retracting
can you please help with PLC ladder program. On how to implement

Good, you have an outline of the sequence.

Now list the inputs for this system. What starts the action? What tells the PLC that each linear actuator is fully forward or fully retracted? List them.

You did not state the PLC. That will be necessary as well as assigning each input and output to an appropriate termination point of the PLC.

Awaiting your next post.

the inputs are as follow
inputs
system running
IR sensor
solenoid
cylinders moving

i have all the information but i am stuck on plotting ladder diagram.

I am asking for all the information which is necessary before writing the first bit of code. You should have already done all of this.

You never mentioned an IR sensor before. You have to be specific.

List the inputs one by one. What does each indicate?
List the outputs one by one. What effect does each output have on the system?

Then, assuming the PLC program is running, what would be the first thing which takes place (usually an input turns on)?

Then, what is the next thing that happens?

Continue on through the sequence. For each step there is SOMETHING which causes it to finish doing that step and begin doing the next. Identify that for each step.

ONLY when you have finished that are you ready to begin writing rungs of ladder logic. Actually, when you have finished that analysis the writing of the ladder logic is rather simple. I'll help more tomorrow (if you want it).

When you walk into a room and turn on the light.
There are two items
1. Switch
2. lamp

The process
A. Push switch
B. switch moves to the ON position
C. The power travels to the light
D. The light illuminates

I know this sounds silly, but, this is a full sequence.
Taking shortcuts is possible of course.
But understanding the sequence first is important

Is this a mock up project or for real production?? We used to service a factory that had dozens of injection molders, and they are a lot more complicated than what you have indicated so far...

This sounds like a student question. Injection molders use hydraulics, as the force, thus pressure, required can be quite high.


SACHEN- You need to show us what work you have done, not just requirements provided by your teacher. There are a lot of knowledgeable and smart people on here, but they will not do your work for you. This is true whether you are a student or a worker with a problem. We will be glad to give advice and point you in the right direction, but if we do your work for you, you will not be able to figure out problems on your own in the future.

You did not state the PLC. That will be necessary as well as assigning each input and output to an appropriate termination point of the PLC.

Click to expand...

Naturally it is the one used in the school lab, the one like all the OTHER hundreds of PLC brands and models in the world - why would there be any difference or any reason to mention the brand and model for the PLC? Obviously this must be a trick question to confuse the student!