PLC Networking

First off, i apologize. I know my PLC knowledge is really really basic. I only know a few small things but I am learning.

At the moment i am taking It classes and learning about PLCs in my spare time and it got me to thinking about this.

How do you network together PLCs ? Is it just a matter of connecting them all to a Switch or Hub ?

Do you have to assign them ip addresses ?

By having all the PLC's networked together, can you manage all of them from one PC ?

there are annumber of methods of 'networking' PLC's
Ethernet is a standard - but it is relatively new.
comonly with the use of switches / hubs or managed switches.
this can be done from a central PC and is common place.
in some factories the use WIFI and use a notebook in the field.

there are other methods of comunication between PLC's some of these are Manufacturer specific.

you need to look up the original comms methods
since you are studying IT
- RS232
- RS422
- RS485
these were the original comms systems

How do you network together PLCs ? Is it just a matter of connecting them all to a Switch or Hub ?

Click to expand...

Yes and no - if you wish to exchange data that has to be set up in the PLCs.

Do you have to assign them ip addresses ?

Click to expand...

Yes.

By having all the PLC's networked together, can you manage all of them from one PC ?

Click to expand...

Generally yes if they are on the same subnet.

The answers I have placed here are fairly simplistic as there a many methods of communications between PLCs and PCs. It depends on the brand of PLC and the software being utilised. Even Ethernet IP is difficult/impossible between different brands.

Thanks so much for the reply.

I took some PLC classes in college a few years ago, so i knew about the RS232 method.

I use RS232 right now to manage Switches/Routers/Access Points so i actually understand a little more now than i did while taking the class.

I bought the Beginners PLC book from this website and i plan on buying the electronics and intermediate book soon.

I just have some questions, but i dont feel right asking them until i really try to help myself first.

never be afraid of the question - we all had to learn some how

I meant to say - look at the differance batween RS422 and RS485
because RS232 is only one to one comms.

If i were to buy alll the books that this website has to offer (and understood them all), and possibly even a little PLC to practice with, Would I have a pretty good enough grasp to work with them in a professional setting ?

www.plctalk.net/qanda/showthread.php?t=52880
look at the links on this post
both from ARCHIE and RON B
these guys have more info and a lot of it is free