PLC Controled Elevator

[testsubject]

I knew that you would jump in eventually...

Mike,

I was waiting to see what you had to say about this subject since you are the resident expert.

Bob

 

[guest]

to elevmike,

Do you think an elevator without sensors, using only rotery encoder on the motor shaft can be done??


because i just had a thought that it might be great to reduce the wiring required for limit switches.


for example for deccelerating,accelerating or stoping the elevator motor,at position..use a comparing bit to compare the car value with the required position(floor).

do you think it woill be safe to do it this way ??


thanx

 

[elevmike]

Thanks Bob,

Guest,

We use rotary encoders all the time for positioning, speed, and direction feedback etc.. However this is a student example so were going to stick with the basics here.

Actually the HSC preset outputs will be the same as the seletor sensors on the car top, UL, DL, DZ, UC, DC. So Yes, but not now for this one.

In the real world there are many other safety features that will not allow the encoder, to cause safety hazards in the event of a malfunction. ASME A17.1 pretty much lays it out for safety on elevators.