12-03-2012, 03:59 PM
programmable logic controller plc
[attachment=18230]
Aim- Study of Programmable Logic Controller.
A Programmable Logic Controller, PLC, or Programmable Controller or Logic Box is
an electronic device used for Automation of industrial processes, such as control of machinery on factory assembly lines. Unlike general-purpose computers, the PLC is designed for multiple inputs and output arrangements, extended temperature ranges, immunity to electrical noise, and resistance to vibration and impact. Programs to control machine operation are typically stored in battery-backed or non volatile memory. A PLC is an example of a real time system since output results must be produced in response to input conditions within a bounded time, otherwise unintended operation will result.
Digital Input / Output of PLC
Digital Input signals behave as binary switches, yielding simply an ON or OFF signal (1 or 0, True or False, respectively). Pushbuttons, limit switches, and photo electric sensor are examples of Input devices providing a discrete signal.
Discrete Output signals are sent using either voltage or current, where a specific range is designated as ON and another as OFF. A PLC might use 24 V DC I/O, with values above 19 VDC representing ON and values below 11 VDC representing OFF. Relay Coil, Solonoide valve etc are example of Output devices.
The maximum number of I/O that can be configured in our system is 8 192 I/O with XP series.
[attachment=18230]
Aim- Study of Programmable Logic Controller.
A Programmable Logic Controller, PLC, or Programmable Controller or Logic Box is
an electronic device used for Automation of industrial processes, such as control of machinery on factory assembly lines. Unlike general-purpose computers, the PLC is designed for multiple inputs and output arrangements, extended temperature ranges, immunity to electrical noise, and resistance to vibration and impact. Programs to control machine operation are typically stored in battery-backed or non volatile memory. A PLC is an example of a real time system since output results must be produced in response to input conditions within a bounded time, otherwise unintended operation will result.
Digital Input / Output of PLC
Digital Input signals behave as binary switches, yielding simply an ON or OFF signal (1 or 0, True or False, respectively). Pushbuttons, limit switches, and photo electric sensor are examples of Input devices providing a discrete signal.
Discrete Output signals are sent using either voltage or current, where a specific range is designated as ON and another as OFF. A PLC might use 24 V DC I/O, with values above 19 VDC representing ON and values below 11 VDC representing OFF. Relay Coil, Solonoide valve etc are example of Output devices.
The maximum number of I/O that can be configured in our system is 8 192 I/O with XP series.
