Beginner need help! Please...

I'm an electrician and I started to learn programming. My dream is to start programming for Siemens.
I spoke with a company more about a job and they gave me a home work to do and learn.

Can someone help me to do this program?
Escalator Program:
An escalator is placed in standby state via a button (S1) [E2.0]
The ready light (H5) [A0.5] indicates that the Escalator is ready.
Escalator ready = light permanently illuminated
Escalator is not ready = light flashes with a frequency of 4 Hz.
The motor starts when people passing the escalator interrupt the photocell (S2) [E2.0].
The drive should be switched on for 20 seconds then.
There needs to be considered: if several people in a row pass the escalator, also the last person must
receive the full 20 seconds of runtime.
The motor of the escalator is (M1_RL) [A1.1]. The movement of the motor (M1_RL) is also visualized
by the lamps H1> H2> H3. (H1) [A0.0]; (H2) [A0.1]; (H3) [A0.2]
Starting with H3, the lights have to rotate while M1_RL is running with an interval of 1.5 seconds.
When button S3 [E2.2] is pushed, the escalator is set out of standby mode again. If a person is
already on the escalator, the actual cycle needs to be ended completely before switching off the
escalator.
If one of the emergency stop buttons (S4_1) [E2.3], (S4_2) [E2.4] (0V=emergency stop) is pressed the
system needs to be stopped immediately and the emergency status needs to be indicated by lamp
(H7) [A0.6] blinking with 1 Hz.

Hi David

First welcome here , this is a great site with very good people always willing to give up their time to help you, but ( ya there is always is a but) you need to make some effort at the program your self first. If you show what you have done people here will give you great ideas and send you in the correct direction.
the time people give here to strangers is nothing like I have ever seen ,so
Just have a go and no one here will not help you because you have tried and maybe not got it fully correct.
You have made a good start by addressing the I/o.
Are you going to use ladder, stl or function block.
Check out or (p) instructions if you are using ladder.

Donnchadh

S1 and S2 on input E2.0 ?

If you're not willing to drive yourself nuts ( and enjoy it ) figuring something out, you are aspiring to the wrong field.

This is the best site there is ... I could not have done much of the little I have been able to do without the generous help of the people on this site.

You give it a go and start it, and the good people here will help you finish it.

Who knows ... I might even know something occasionally.

And I apologize for posting this AFTER your second post ...apparently we were typing at the same time

Is this a siemens controller? I am unfamiliar with the nomenclature... It appears that E is an input and A is an output.
I think the switch and the photocell should be on different inputs... particularly since the photocell is detecting people walking by to get on the escalator and is performing a different function than the switch

Why don't you start by creating the logic to turn on the standby lamp with one push of the button S1 and turned off with a push of S3?

If you're not willing to drive yourself nuts ( and enjoy it ) figuring something out, you are aspiring to the wrong field.

Click to expand...

Realolman,
That is one of the best description of what we do that I have ever seen!! Mind if I use it in the future?

David,
Realolman is correct, start small. Break each task down into smaller program pieces. It is way to easy to look at the complete spec and get overwhelmed. look at one thing at a time and try and accomplish that task.

You could even write down some Pseudo Code to get you start. In case you don't know what that is, it is just writing down the steps using simple language terms like NOT, AND, OR, IF, THEN, ect. This might help you when you actually get on the computer. I used to do it all the time when I was starting out. I dont do it so much now on paper but I find that I do it in my head.

Example:
IF NOT S1 THEN elevator_ready (you will need to know more about the button S1. Is it a momentary Push Button or is it a push to set/push to reset. That will determine how you write the logic. If it is a momentary PB then research Flip/Flop on this site)
IF elevator_ready THEN H5 is on
IF NOT elevator_ready THEN H5 flash (you will need to use a couple of timers for this. One to time how long the light is on and one to time how long it is off.)

Hopefully this makes sense to you and helps you on your journey.
Good luck.

I got 2 pdf for this program.

Bullzi said:

Realolman,
That is one of the best description of what we do that I have ever seen!! Mind if I use it in the future?

David,
Realolman is correct, start small. Break each task down into smaller program pieces. It is way to easy to look at the complete spec and get overwhelmed. look at one thing at a time and try and accomplish that task.

You could even write down some Pseudo Code to get you start. In case you don't know what that is, it is just writing down the steps using simple language terms like NOT, AND, OR, IF, THEN, ect. This might help you when you actually get on the computer. I used to do it all the time when I was starting out. I dont do it so much now on paper but I find that I do it in my head.

Example:
IF NOT S1 THEN elevator_ready (you will need to know more about the button S1. Is it a momentary Push Button or is it a push to set/push to reset. That will determine how you write the logic. If it is a momentary PB then research Flip/Flop on this site)
IF elevator_ready THEN H5 is on
IF NOT elevator_ready THEN H5 flash (you will need to use a couple of timers for this. One to time how long the light is on and one to time how long it is off.)

Hopefully this makes sense to you and helps you on your journey.
Good luck.

Click to expand...

This makes sense. Thanks Bullzi.

There needs to be considered: if several people in a row pass the escalator, also the last person must receive the full 20 seconds of runtime.

Click to expand...

I will give you a quick hint for this function. Use the Photoswitch S2 Input to reset your 20-second RUN Timer (move "20" to the timer Preset Value) each time a new person passes. That will make sure that the last one receives the full 20 seconds.

Lancie1 said:

I will give you a quick hint for this function. Use the Photoswitch S2 Input to reset your 20-second RUN Timer (move "20" to the timer Preset Value) each time a new person passes. That will make sure that the last one receives the full 20 seconds.

Click to expand...

Thanks for the tip Lancie1.

I am willing to pay for helping me for this program.

bad idea

If you want to start working in the field, you should do it alone. Half of the fun is figuring out how to do it.

I am sure someone here will end up giving you the solution, especially if you start offering money, but is that how you want to start at a company. By lying about writing a very basic program?

Regarding the using of E and A, this is the German annotation for I inputs and O outputs.

Regarding the using of E and A, this is the German annotation for I inputs and O outputs.

Click to expand...

From the picture of the PLC, it appears to be a Siemens Simatic S7-300 with a 315-2 Central Processing Unit.

So we need some of the Siemens guys to come in here and make some suggestions.
Does this CPU have a clock bit that flashes 4 times per second that could be used to flash the "Escalator Ready Lamp"? (Maybe one of the OB10 Clock Interrupts)?

Yes. You can enable the clock byte in the cpu settings. One of the should be 4 hz. If not it can be easily implemented by using a odt timer.