PLC UNIT 1

PLC has replaced__________

• Transistor

• Computer

• Relay Logic

• Solenoid

PLC stands for_______

The PLC with maximun of 32 I/O is called as ___________PLC.

If the I/O Count of PLC is between 32 to 128 then it is called as ___________.

• Micro PLCs

• Medium PLCs

• Small PLCs

• Large PLCs

In PLC the user program is stored in ________ memory.

• ROM

• PROM

• EPROM

• EEPROM

Input modules provide an interface between ______________and_____________.

• Input connections and the CPU

• Field equipment and the CPU

• Output modules and field devices

• The CPU and output modules

Electrical isolation is provided so that there is no physical electrical connection between the CPU and output field devices. This isolation is usually accomplished by____________

• Power supply 

• Rectifier

• Opto coupler

• Holding Register

1KB of memory is equal to ________

• 1000 bits

• 1000 words

• 1024 bytes

• 1024 words

The basic difference between plc and relay control system is ___________

• Different input and output voltage levels are used

• Different types of output devices are used

• Different types of input devices are used

• One uses relay control logic & other uses programmed instructions

Power signal that the output module switches to control field devices must be provided by__________

• The CPU   

• The user

• The master control relay

• Relay