# 2 way motorised ball valve for open/brewtroller



## cat007 (4/2/13)

Hey all

I'm building a rig with the OpenTroller/BrewTroller.

I have the option for a 3 wire ball valve like the open/brewtroller asks for. The second option I have is a 2 wire ball valve with a capacitor return function - so when power is applied to the valve it opens and charges the capacitor and then when power is removed the capacitor closes the valve again.

The main problem I see is that if the valve is set to open/close in a short space of time - there might not be enough time to charge the capacitor and therefore close the valve.

What do you guys think I should do?

Cheers
Hunt


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## newguy (5/2/13)

What size is the capacitor and what is driving (powering) the valve? If the cap is being driven from a power supply line, it will charge nearly instantaneously. If it's being driven from a logic line, yes it will take some time to charge, but probably in the range of hundreds of milliseconds to maybe a few seconds. Again, it depends on the size of the cap.

Total charge time is 5 tau where tau = RC. R = resistance of what is charging the cap, in ohms, and C is the capacitance of the capacitor, in farads.


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## cat007 (5/2/13)

Thanks for the reply. I will have to confirm the size of the cap. 

It will be driven from a SSR and a 12v power supply.


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## tavas (5/2/13)

Hey all

I'm building a rig with the OpenTroller/BrewTroller.

*I have the option for a 3 wire ball valve like the open/brewtroller asks for. *

I think there's your answer. Keep it simple.


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## cat007 (5/2/13)

Yeah - the ol' K.I.S.S. theory aye! I'll go for the 3 wire like it's suggested.


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## MastersBrewery (5/2/13)

Now I haven't been on the brewtroller site for a while but there was talk of a work around for partial openings so automated flow control could be achieved, to achieve this I believe the 3 wire would be required. Keep it future proof and stick with the 3 wire


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