ladder logic help, please

[adymack]

Hi Everyone,
I am trying to write a program that has 2 pumps, 1 in-standby and 1 in-duty, the pump in-duty starts and if tripped then the pump in-standby comes on and vica-versa.

I have a running, tripped, start and stop input and obviously an output for the duty pump and an output for the standby pump.


I thank you inadvance for all your help.

Adrian

 

[Grossel]

What is the problem.

You have drawed the diagram and the PLS works? Or doesn't it works? How does it misbehave? Can you upload your layout?

 

[adymack]

I am having difficulty doing the diagram, i can do the pump control circuit including the tripped signal but i cannot work out how to bring the other pump on after the duty pump has tripped and then vica-versa.

 

[Kirkgang]

Would not a lead/lag set-up work? If you have the tripped signal in place, then the lag pump would operate via dip tube or float switches until the lead pump problem could be fixed. Tripped could be main, fuse, overloads, ect. Hard to cover all these without getting to complicated.

 

[Avi22]

Helo,

I'm trying to write a similar program including the following additional features:
1. The two pumps are to be controlled though 3 float switches
2. Lowest level float switch "FS0" to stop all pumps. When level reaches float switch FS1, pump 1 starts and if level reaches float switch FS3 2nd pump is to start.
3. The pumps are to alternate in running..(flip-flop)?

Grateful if anyone has a ready made program for this.

rgds

 

[Avi22]

Helo,

I'm trying to write a similar program including the following additional features:
1. The two pumps are to be controlled though 3 float switches
2. Lowest level float switch "FS0" to stop all pumps. When level reaches float switch FS1, pump 1 starts and if level reaches float switch FS3 2nd pump is to start.
3. The pumps are to alternate in running..(flip-flop)?

Grateful if anyone has a ready made program for this.

rgds