Check Yourself!

The output should only switch to state “1” if only one input has a logical “1” at a time. Which logical function do you have to use here?


Logic NOR


Which logical function is represented in this truth table?


Which statement about the following logical function is correct?

Interlocking Outputs in PLC

Interlocking Outputs in PLC


A fan should run (Q1 = 1) when the main switch is actuated (S = 1), the temperature sensor (bimetal) reports overtemperature (T = 0) and the motor is running (S2 = 1). Which logical function can be applied to this task?

PLC Ladder 2

PLC Ladder 2


Which statement about the function of this PLC program is correct?

PLC - 2 from 3 circuit

PLC – 2 from 3 circuit