catalinoac
Member
- The original limit switch wiring configuration on Door Simulation are
LS1 = N.O.
LS2 = N.O.
Upon reading on the exercise, there is a "For Discussion" in which the
the LS2 (lower) may be rewired to N.C. for "fail safe design" operation.
<u>
[*]Upper Limit switch wired N.O., Lower limit switch rewired N.C. resulting in:
Upper limit switch (door open) goes False(0) when Door reaches the fully open position.
Lower limit switch (door closed) goes False(0) when door reaches the fully closed position.
- </u>With the wiring configuration of LS2 change from N.O. to N.C. would result in a fail-safe (OPEN CIRCUIT) protection. (As the motor will not run down if the circuit on limit switch is open)
My question is, how about "SHORT CIRCUIT"? If LS2 will be shorted, then motor will run down (when PB closed is pressed) and will NOT STOP down to LS2 (as LS2 is shorted)