Difference between a plc and microcontroller

[sskki]

What is the difference b/w a plc and a microcontoller since a plc contains a microprocessor, memory, interface ports like a microcontroller. and working of plc is similar to that of microcontroller

 

[Pierre]

A PLC will not fit in your wallet, a microcontroler will.
A PLC has nice LED on its cover, a microcontroler has no cover.
A PLC can sometime be snap unto a DIN rail, a microcontroler cannot.
A PLC has inbeded smoke which can be released with various technique, a microcontroler will just change from glossy black to black.
A PLC is a 3 letter word, a microcontroler has more.
A PLC can make a nice traffic light system on its own, a microcontroler need other parts connected to it.
A PLC cannot be welded to a circuit board, a microcontroler can.
A PLC can communicate to the rest of the world, a microcontroler cannot.
An old PLC can old my office door open, a microcontroler cannot

Want more?

 

[JAG]

If you really want to know, a microcontroller is just a limited microprocessor chip usually programmed in assembly language. It requires hardware be connected to it before it can do anything useful. Even though more advance now, older PLC's required a form of a microcontroller in it to run.

 

[BobB]

PLCs have in built watchdog timers that are monitored by the firmware and they check the programme from one scan to another. If the programmes do not match, or the watchdog timer times out they shut down.

 

[Leonardo2003]

A PLC is a 3 letter word, a microcontroler has more.

I dont think so..it just happen that he did not completely writes the meaning of PLC. Since he mentioned only plc...I agree with you...