Quiz 1 Chapter 1 PLC

The control plan stored in the PLC is called:

• a program

• a Boolean ladder

• FORTRAN

• a microprocessor

This symbol in a ladder logic diagram:

• can be thought of as a normally closed contact.

• can be thought of as a normally open contact.

• represents a capacitor.

• is always at logic 1.

This symbol in a ladder logic diagram represents a(n):

• set of normally open contacts.

• imaginary coil that, when energized can close an output interface contact.

• contact that will seal itself in once it closes

• field load or sensing device

Any change to a PLC program normally involves some change in wiring as well.

• True

• False

To operate the program, the controller is placed in the PROGRAM mode.

• True

• False

An instruction is a command that will cause a PLC to perform a certain predetermined operation.

• True

• False

During each operating cycle, the controller examines the status of output devices, executes the user program, and changes inputs accordingly.

• True

• False

A PLC has no keyboard, CD drive, monitor, or disk drive.

• True

• False

PC based control systems require the use of interface cards.

• True

• False

Which of the following is not a criteria for classification of PLCs?

• number of inputs and outputs

• cost

• physical size

• manufacturer