Programmable Logic Controller (PLC) Questions and Answers – 2

Suppose we have a PLC connected to three process switches as shown in this illustration:

PLC Questions - 2

In the above diagram :

  • X1 to X4 : Inputs
  • Y1 to Y4 : Outputs

Determine the switch actuation statuses (i.e. low versus high process stimulus) given the “live” display of the ladder logic program shown here:

PLC switch actuation

Also, determine the status of the lamp connected to the PLC’s Y1 output.

Answer : 

  • High pressure and low flow and low temperature.
  • The lamp will be de-energized.

Share Your Answer / Comments

Credits :  Tony R. Kuphaldt – under CC BY 1.0

For More PLC Questions : CLICK HERE


1 thought on “Programmable Logic Controller (PLC) Questions and Answers – 2”

Leave a Comment