Automation - Unit 1

PLC Stands for

• Programmable Logic Controller
• Programmable Logic Circuit
• Programmable Logic Computer
• Programmable Level Controller

PLC parts are mounted on

• RACK & CHASIS
• Isolation Stages
• Program Monitor
• OPTO isolators

The abbreviations NO and NC represents the electrical state of switch contacts when_______________.

• Power is applied
• Power is not applied
• The switch is actuated
• The switch is not actuated

NC push button connected in hardware & NC contact in software then the coil connected to the NC contact will be ___________.

• ON
• OFF
• Short
• Toggle

A limit switch is usually actuated by_________.

• Hand
• Pressure
• Contact with an object
• An electromagnet

A thermocouple ,when heated _______.

• Produces a small dc voltage
• Increases its resistance value
• Produces a small AC voltage
• Decreases its resistance value

PLC uses _____ Design .

• Assembly
• Command
• Manufacturing
• None of the above

__________ is used to communicate with PLC .

• Analog Module
• Input Module
• Program Monitor
• Debugger

PLC has replaced.

• electronic circuit
• relay logic
• computer
• none

Disadvantage of PLC is .

• security
• too many contacts
• pilot running
• fixed program application