Page 24 - AUTOMATION EISBN

• Example of Output: Lamp, Motor, Solenoid

2.1.4 Function and Operation Of The Hardware Units

a) Housing Unit.

b) Programming Unit.

c) Program Loader Unit.

d) Secondary Storage Unit.

e) VDU Unit.

f) Power Supply Unit.

g) Printer Unit

Housing Unit

• Protect PLC circuit and internal component

Programing Unit

• Programming Console

• Hand-held programming devices are sometimes used to program small PLCs

• A personal computer (PC) is the most commonly used programming device

Program Loader Unit

The programming terminal, or loading terminal, is used to program the CPU. The

type of terminal used depends on the manufacturer and often the preference of

the consumer. Some are small handheld devices that use a liquid crystal display

or light-emitting diodes to show the program. Some of these small units will

display one line of the program at a time and others require the program to be

entered in a language called Boolean.Another type of programming terminal

contains a display and keyboard. This type of terminal generally displays several

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