# Reversing actuator with one signal wire



## Dewey G (Jul 26, 2012)

I have an irrigation well that delivers water to 3 different center pivots. I can remotely control all the pivots, but cannot control where the water goes. Each center pivot has its own control panel that signals the electric motor that pumps the water. This signal is always energized when the pump is on. It is 120 vac

I want to take this signal wire and have it open or close an 8" electric valve. The valve will open anytime the pivot is telling the pump to be on.

The actuator is 3 wire, also 120vac. I need it to be normally closed, it needs to open when the signal wire is hot. When signal power is lost I need to reverse polatiry to close the actuator.

What do I need? Diagrams would be helpful. 
Thanks


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## nolabama (Oct 3, 2007)

dewey i hate to tell you but if your the electrical engineer your the one that has to draw the diagram and then the electrician will wire it up for you:thumbsup:


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## McClary’s Electrical (Feb 21, 2009)

11 pin octal base relay with 120 volt coil.


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## nolabama (Oct 3, 2007)

mcclary's electrical said:


> 11 pin octal base relay with 120 volt coil.


they dont mention this in engineering school these days?:blink:


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## Dewey G (Jul 26, 2012)

Lets just say I havent found anyone else locally who wants to handle this or I wouldnt be figuring this out on my own.


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## Jlarson (Jun 28, 2009)

Your valve actuator probably (what model valve, can you provide a cut sheet??) has open and closed limit switches so in that case all you need is a ice cube relay like mcclary's mentioned already. 

The 120 from the pump panel goes to the coil. Use the relay's NC contact to close the valve and the NO contact to open the valve.


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## nolabama (Oct 3, 2007)

Jlarson said:


> Your valve actuator probably (what model valve, can you provide a cut sheet??) has open and closed limit switches so in that case all you need is a ice cube relay like mcclary's mentioned already.
> 
> The 120 from the pump panel goes to the coil. Use the relay's NC contact to close the valve and the NO contact to open the valve.


I thought you only have voltage when the pump is on. Pump on valve open signal is On. Pump off valve closed no electricity to close valve? Your way sharper than me with this tho. I guess the question I am trying to ask is this. All actuators that sizeI have seen need power to open and power to close. I have seen smaller ones that normally closed has a spring that closes them but not that big. I guess they make em tho.


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## don_resqcapt19 (Jul 18, 2010)

nolabama said:


> ... I have seen smaller ones that normally closed has a spring that closes them but not that big. I guess they make em tho.


Yes they make "fail close" and "fail open" valves that return to the fail position in larger sizes. They are very commonly used in industrial process applications for "fail safe" reasons.


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## nolabama (Oct 3, 2007)

don_resqcapt19 said:


> Yes they make "fail close" and "fail open" valves that return to the fail position in larger sizes. They are very commonly used in industrial process applications for "fail safe" reasons.


Cool to know. Then this guy has his corn waterer whipped.


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## Jlarson (Jun 28, 2009)

nolabama said:


> I thought you only have voltage when the pump is on. Pump on valve open signal is On. Pump off valve closed no electricity to close valve? Your way sharper than me with this tho. I guess the question I am trying to ask is this. All actuators that sizeI have seen need power to open and power to close. I have seen smaller ones that normally closed has a spring that closes them but not that big. I guess they make em tho.


I figured the guy was putting the valves at the well where there was power to run all the actuators.


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## Dewey G (Jul 26, 2012)

Thanks everyone. I've got it figured out now.

Yes, the valves I'm using are power open, power close, and have their own internal limit switches.

Spring return valves are common in smaller sized valves, but are not cost effective in an 8" valve like I need.

I will be installing a pressure cut-out to kill the pump should a valve not open. Valve open time is 27 seconds. I'm pumping 800 gallon/min from 300' deep, and then it will need to travel over 1000' to the valve, so given the velocity of the water in the pipe, 27 seconds will be fast enough without using a time delay for the pump

Thanks again


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## alpha3236 (May 30, 2010)

http://www.fresnovalves/controll.htm 

We use these at the pivot center point. water pressure closes the valve, a 120vac solenoid opens it. the pressure switch is a must to prevent main line blowout. if the pump is an electrical turbine type, you should definately use a TDR to prevent starting up during backspin after a short power outage. don't want to unthread the shaft, very expensive to repair.


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## Dewey G (Jul 26, 2012)

The pivot panels have built in delay after a power outage. The 9300 series valve is similar to a nelson 800 series.

I never checked on a price on those valves because I can get an actuated wafer style butterfly valve that will be a direct replacement for the manual valves I have. Less labor to replace since I dont need to cut pipe, and re weld flanges to make room for the wider valve you show.

Out of curiosity, what is the price of a 6" 9300 valve?


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