Question

1. What would happen if the input device PX1 failed to produce an output, causing no input on IN14 of

the roll stand's PLC?

A. The arms would not lower after the roll of paper was finished and the arms lower push button is pressed.

B. Both motors M2 and M3 would run until they tripped their overloads.

2. If the RUN light on the CPU of a PLC is not illuminated, what should be your next action or check?

A. Check the power supply's indicator light.

B. Issue a START command at the console or laptop.

C. Check for a COMM error light.

D. Replace the CPU.

C. The arms would continue to open until LS1 and LS4 actuate.

D. Motor M1 for the hydraulic system would keep running.

Answer 1

1. Unable to answer this question. I need a PLC ladder diagram of the roll stand machine to give you a answer

2. If the RUN light of the CPU is not illuminated, do the following actions,

• Check the power supply and check the power indicator light is ON..
• If power indicator light is ok, then check the /COMM error indicator light
• If there is no error, check the PLC whether it is in RUN or STOP mode. If it is in STOP mode change it to RUN mode.
• If still the RUN indicator light not illuminated, then start the PLC with the console / laptop.
• If still the RUN not illuminated, replace the CPU