the diff. in the applications of PIC & PLC

[h.d]

hi
am want to now whats the diff. between PIC & PLC in the applications that can it used for.
for more determination:
in my project i need to connect keypad, can i use PLC for that
and which types of PLC should use.
i think the PIC is more usable for that, isnt it?

 

[JimB]

A PIC is a component, it requires other components before it can be made into something useful.

A PLC is a fully engineered controller suitable for use in an industrial environment.
It can be a simple "one box" solution to a small problem, or it can have many I/O modules plugged into a backplane to control an very large machine, or a whole factory.

JimB

 

[SPDCHK]

Depending on what the application. Like JimB said, some PLC's come as a contained 'One box' or as we call it 'Black Box' that offers some 8 DI (Digital Input) and 4 DO (Digital Output). These small units seldom allow for any analogue signals though.

Most PIC's can handle the same IO but unlike the PLC where the IO is 'Wire and Go', with the PIC you will need circuitry to connect the IO to the PIC. With some PLC's you get the programmer tool software with the purchase of the unit. (Most case for the small units it might be Ladder). With PIC you have all the different packages available, some for free (i.e. MPLab), and the others (like C compilers etc.) will cost a pretty penny.

Connecting a Keypad to a PLC is most often a waist of IO. PLC's make use of dedicated protocols like Modbus (antiquated by now) PROFIBUS and many more to connect peripherals like Display panels, industrial keypads, smart IO and many more.

The main difference in short... THE COST.

 

[Nigel Goodwin]

This is like asking what's the difference between a TV set and a resistor, one is a complete project and the other a component.

Where a bit of confusion arises though is that many (most?) modern PLC's are just pre-programmed PIC's (or other micro-controllers).

 

[h.d]

OK thnks for replays
am work in project for treadmill design & implementation
so i should determine the controller which i will use
there r many of it but i can deal with PIC & PLC
so i want to know which one of them is more usable?
i think PIC is the true choice,isnt it?
but the PLC maybe easiest but expensive.
is it true????

 

[Nigel Goodwin]

It's an application for a PIC, not really for a PLC - a PLC is a LOT more expensive, and won't be anywhere near as good for this job, and may not even be able to do some things the PIC can.