what wire is best for 12vdc solenoid valve at 800 feet?
what wire is best for 12vdc solenoid valve at 800 feet?
(OP)
We have built an air actuated gate valve that needs to be controlled by a radio receiver located 800 feet away. The receiver puts out 12vdc. 460vac and 120vac are also available where receiver is. I designed an air operated control system which works OK to close the valve on application of pressure, but is too slow to open the valve on pressure bleed-off. I had an air line available to valve location, and have an open pvc conduit available for control wiring. Primary wires for 3-phase 460vac runs in conduit next to open conduit. Two vfds are supplied off this circuit. What is best wire type, voltage to run controls at this distance for our Vectorr atmospheric train? Can I run a solenoid air valve directly off of the radio output, or should I, as SCOTTYUK suggested in an earlier thread use a SSR?





RE: what wire is best for 12vdc solenoid valve at 800 feet?
If you have 120 Vac and a reciever that can deal with 120 Vac, then use the reciever to operate a 120 Vac solenoid.
RE: what wire is best for 12vdc solenoid valve at 800 feet?
RE: what wire is best for 12vdc solenoid valve at 800 feet?
Mike Halloran
Pembroke Pines, FL, USA
RE: what wire is best for 12vdc solenoid valve at 800 feet?
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If we learn from our mistakes I'm getting a great education!
RE: what wire is best for 12vdc solenoid valve at 800 feet?
"...engineering is the art of doing for 10 shillings what any fool can do for a pound". Duke of Wellington Arthur Wellesley
RE: what wire is best for 12vdc solenoid valve at 800 feet?
"...engineering is the art of doing for 10 shillings what any fool can do for a pound". Duke of Wellington Arthur Wellesley
RE: what wire is best for 12vdc solenoid valve at 800 feet?
RE: what wire is best for 12vdc solenoid valve at 800 feet?
When the line is exhausted the pressure will drop on a curve similar to a capacitor discharge curve. You may want to try a pressure switch that will operate an electric dump valve when the pressure in the air line starts to drop. You may be able to get the response time down to about a second. You may have to install a local reservoir and use a two way valve and check valve.
A pressure rise may be used with the same pressure switch and solenoid valve to extend the cylinder.
Bill
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"Why not the best?"
Jimmy Carter
RE: what wire is best for 12vdc solenoid valve at 800 feet?
"...engineering is the art of doing for 10 shillings what any fool can do for a pound". Duke of Wellington Arthur Wellesley
RE: what wire is best for 12vdc solenoid valve at 800 feet?
It is assumed that a system will reach equilibrium in about 5 time constants.
So at 12 seconds to empty the system, one time cycle will be about 2.4 seconds. At the end of one time constant the pressure will have dropped 63%. If we take 100%-63% = 37% as the equilibrium then our time constant becomes 0.48 seconds. 100% -(63% x 37%) = 77%
In about 1/2 second the pressure should drop to 77%.
If we go one step further, in about 0.1 second the pressure will have dropped to about 86%.
I hope I haven't made any mistakes and I hope this helps.
Bill
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"Why not the best?"
Jimmy Carter