Electrical Questions

NoseyMike2010

Hope someone can help me here.

1) What is Profibus?
2) What is Genius Bus?
3) What is a firewall PLC?

2011

1) Profibus is a standard for field bus communication with PLCs and automation systems. Profibus uses 2 wires and can be used for connecting PLCs and remote I/O modules together so they can "talk" to each other. Often complex equipment such as VSDs and various types of instrumentation would be connected to a PLC with Profibus cable. Rather than using a series of discrete and analogue I/O 1 profibus cable could transfer vast amounts of information. For example a VSD might communicate the following signals on 1 Profibus cable: Start, stop, run, Estop engaged, trip set point, winding temperatures, current speed, current drawn per phase, output frequency etc.

Many different pieces of equipment could be daisy chained on the same Profibus cable, each with it's own address. Siemens are one of the main PLC manafactures that use Profibus.

2) Genius Bus. I imagine it is similar to Profibus, but made by someone else. I have never used this.

3) I don't know much about this to be honest.

2011

3) I asked some people at work. They believe that is simply a PLC that is installed on a network behind a firewall so that comms traffic can be controlled.

NoseyMike2010

2011,

What type of PLC systems do you work on?? Do you use GE Fanuc?

2011

So far Siemens and Allen Bradley. I still have lots to learn to be honest. Most of the time I am working with instrumentation, but there is plenty of overlap. The team I work with are very experienced so I am lucky in that respect.

NoseyMike2010

Allen Bradley looks interesting. Is it easy to learn? Where should I start if I was to learn about how they work.

Remember I am starting form Rock Bottom!!!!!!!!!!!!!!!!

2011

They are American and are very popular in the industrial world. I have never programmed an Alan Bradley to be honest, that is not my job. Basicaly all PLCs work on the same principles. If you can programme one type you and understand a bit of control theory you can adapt.

Remember ladder was designed so that electricians can understand it easily. That is why it is so visual. If you are a sparks you will learn ladder quickly. It is similar to hardwired relay logic, but can get more complex when you want it to do things like complex mathamatical calculations.

Allen Bradley looks interesting.

All PLCs are interesting IMHO.

Philistine

2011 wrote: »

All PLCs are interesting IMHO.

Couldn't agree more.

If you can program one you can easily adapt and program all. Ladder logic is the same principle for all manufacturers. You just need to familiarise yourself with the different terminology.

NoseyMike2010

What book/website would you recommend for someone to get their head around ladder logic.

Thanks again for the websites. Didn't know Siemens are involved in PLC's too!!!!!!!!!

2011

What book/website would you recommend for someone to get their head around ladder logic.

IMHO you could read books on programming PLCs forever, but the best way to learn is to do it. The best way to do it is to do a course. There are some excellent short courses that you can do. I did a short one about 15 years ago in DIT and I think they still run it. It was only 1 night a week for 10 weeks. After a short course like that you will "get the bug".

NoseyMike2010

Do you know of any courses that I can do online. Distance learning type courses. I am not living in Dublin anymore.

2011

No, sorry. I am sure there are lots of places that you can do a course though. The only way really to learn is by doing using books only to assist I would think.

NoseyMike2010

What is the purpose of a terminal like the one on this link??

http://catalog.weidmueller.com/catalog/Start.do?localeId=en&ObjectID=1023500000

NoseyMike2010

And why do you need isolator switches lik

http://www.abb.com/product/seitp329/25fd8b166ddc692fc1256e91002982dd/pis_ABB1SCA022352R6950.aspx?tabKey=2

1) What is there purpose?
2) How do you descide when you need one?


Thanks in advance.

NoseyMike2010

Any ideas ... or were these really stupid questions ... lol!!! Sorry !!!