tedbear - 8/2/2024 04:16

I have used a Hudson with good success for several years BUT my situation is to fill a tank that is permanently located in my mixing shed. I had a friend who tried to use one in a portable situation such as you describe. His results were not good partly because where he needed to park for filling was not level. Therefore I agree that a Hudson is probably not the best approach for your situation.

A couple of years ago, I purchased a Chinese float system that might work for your situation but I have not actually used it. I was intrigued by it and basically purchased it on a Wim.

It does involve electricity so there may be some reluctance in that respect. The "electric" part could be either regular line voltage AC or 12VDC. My thought was to use 12VDC from a regular battery such as the vehicle in your case. This would also eliminate any concerns about lie voltage and water. It would require a 12VDC ON/OFF valve in the water line. The float mechanism would open or close this valve unattended.

I thought the float mechanism to be unique and quite clever. It consists of a float that is tethered to a fixed point somewhat below the top of the tank. This could be a small arm or stand of some sort. The tether which in effect is the float linkage arm is a 3 wire electric cord which leads from outside the tank down into the float inside the tank to be filled. There is a ball inside the float which can contact a Single Pole Double Throw switch which is mounted inside the float on one end. By tipping the float in my hands, I can hear and feel the ball roll from one end to the other.

The idea is that when the tank level is low, the float will tip downward because one end is tethered to the stand and the internal ball will roll inside the float to the lower end and push the switch which connects the common wire to one of the other wires. When the tank level is high the float will tip upward and the internal ball will roll to the other end and no longer push the switch. The switch then connects the common to the other wire.

This means that by using the common and one of the wires, the float system will make contact when the float is low but break contact when the float is high for filling.

This could also be used with a sump pump to empty a tank by using the common and the other wire. Then the pump could run while the level is high but stop when the level is low.

Some experimentation would be needed to get the tether "pivot" point at the desired height in the tank. The length of the cord from the float to the tether pivot point is adjustable which would determine the dead band between where the ball rolls toward one end or the other. If the tank has an access cover on top, it might be fairly easy to mount some type of arm or stand to it. The depth and the length of the tether cord would need to be adjusted by experimentation.

The advantage to such a system is that the linkage arrangement is rather fool proof in that it is so simple. It could bounce around while you are driving to/from the field without much danger of damage or failure. I would have a master switch in the 12VDC line so the valve would not cycle while driving around due to sloshing or a low tank. When you get back to your water source, connect the hose and flip the switch.

This float assembly was very inexpensive although although there would be the cost of the 12VDC ON/OFF valve, some wiring and plumbing.

This is what mine looks like. This one does not specifically state that it uses a double throw switch but implies that it can be used either way. I have purchased from this online source several times. The merchandise is Chinese but I've been happy with their products and service.

https://www.temu.com/float-switch-for-sump-pump-float-switch-for-wat...