4-20, 0-10, 0-100... What are all these?

[Roccane]

Congratulation for the level of your forum!

And here is my question.
I work as electrician and we build electric cabinets for automations. I am not the chief electrician but as far as automation is concerned, i do it fine.
I want to go a step more. I want to start working with temperature transmitters, indicators, PLCs and stuff. Can someone tell me a walkthrough or something that i could start learning? What should i buy to work with for example? A PLC? Transmitters an dindicators?

Any idea could be good 

[serafino]

First of all wellcome.
I am working with all these that you describe to us.
You can start to study with all of these together    and of course  you can buy a small plc.
It's very important to have your work shop.
We can help you .

[spic0m]

Can you recomend something serafino, brands etc.?

[kam]

You can start to study with all of these together   

Come on man you own this subject
Give him your lights. Not all together for a start.

[Roccane]

First of all wellcome.
I am working with all these that you describe to us.
You can start to study with all of these together    and of course  you can buy a small plc.
It's very important to have your work shop.
We can help you .

Serafino, if i start with everything, i will end with nothing.

[serafino]

ok, what is 4-20. You mean 4-20 mA i hope . This the classic electric anolog signal.
The transmitters have output 4-20 mA  (and not only).
What exactly you want to learn ? ( sorry but i don't know what you know about all these )

[Roccane]

ok, what is 4-20. You mean 4-20 mA i hope . This the classic electric anolog signal.
The transmitters have output 4-20 mA  (and not only).
What exactly you want to learn ? ( sorry but i don't know what you know about all these )

What exactly i want to learn? I do not know. That is the problem. The problem is that i do not know. And this  happens with people that try to learn and do not know. The do not know what to learn.

I want to know to make for example an alarm when temperature goes too high, that will sound a siren. Simple things but made with PLC. That's it

If you know then write a walkthrough or a tutorial or something. How would you make one? What would you use? What materials? And a program. Write a well commented program.

[serafino]

For high temp.  alarm.
you use one  temperature sensor  (for ex. pt-100 , range 0 -150 Celsium).
This sensor connected with transmitter which transmitter use input PT-100 and output 4-20mA.
So you have the signal signal and one choice is to use plc with analoge input .
So you connect the signal direct in one input of plc.After work with software and connect one horn in one output of plc .( i have photoes but i cannot find them  now , i must organised for help you)
The other easier choice is to connect the electric signal direct with one controller which has input 4-20mA and also digital output.
look this photo ( not so good ) one temp. controller.

[serafino]

look this example

[serafino]

Here i have one temperature sensor PT-100 type , one prerssure transmitter , and one controller .

[serafino]

sorry, here are the photos

[Roccane]

WOW serafino!!! Thanks

And in your drawing, why do you have 2 temperature sensors? One you name it "temperature transmitter" and other is name "PT100 temperature sensor".

Why you put 2? And what is this tank?

[serafino]

Tank is for example.
Temperature sensor is the sensor ( pt-100 is one type of temperature sensor ).
Output of this sensor is resistance ( Ohm ) and you connect with temperature transmitter and you have 4-20mA.
but there is also temperature transmitter which included inside temperature sensor and you have directly 4-20mA.

[serafino]

All these analog signals you can connect them with a plc and you can make all the control from it.

[Roccane]

Temperature sensor is the sensor ( pt-100 is one type of temperature sensor ).
Output of this sensor is resistance ( Ohm ) and you connect with temperature transmitter and you have 4-20mA.
but there is also temperature transmitter which included inside temperature sensor and you have directly 4-20mA.

Why do you use 2 temperature sensors? For security? If one fails?

All these analog signals you can connect them with a plc and you can make all the control from it.

Can you show me an example how? The program i mean. If for example you have to do this project, what would you make?