Home Automation - water well automation

i have a bit of an electrical control problem that i cannot figure out. i have drilled a well for 2 purposes. 1: fill a pond; 2: irrigation. the pond fill and irrigation are controlled by seperate solenoid valves. the problem is this: i need the pond solenoid to open (be energized) at all times, until the irrigation system comes on. at that point, i need the pond solenoid to close and the irrigation to open. the irrigation system has a 24 volt ac master timer. the only solution that i can come up with is using a double pole contactor with one normally open contact and one normally closed contact and a 24 v coil. i cannot find anything like this at any supply house. any help would be greatly appreciated.

Are you trying to control the pump in/for the well? If the valve to the pond is open at all times except when the irrigation system is supposed to be running then what will start and stop the well pump?

You may not find a contactor (or better, a motor starter) that has the necessary contacts but designing and installing a control system ahead of the pump control would be a fairly simple job IF I knew all the details.

Use a double-pole double-throw 24-volt relay to control the contactors. The pond would be on the normally-closed contacts and the irrigation system would be on the normally-open contacts. When the timer energizes the coil the relay will shut off the pond and turn on the irrigation system.

You may not need to put the irrigation system on the relay if it controls its own contactor. Just tap the 24-volt control voltage to power the relay for the pond. When the timer powers the relay, its contacts will go open and stop the pond pump.

the well pump is a 5 hp sub drive that I installed. there is a 120 volt solenoid valve on the line that fills the pond and on the irrigation line. the well pump is not the problem at hand. it maintains pressure to these solenoid valves. all i am after is a way to close one valve when the other one opens, and vise versa.

All you would need is an alternator and two, two pole contactors. The sprinkler controller would operate a set of contacts controlling the alternator, witch would switch on and off, either the pond or the sprinkler solenoid.


Travis