It is over five months that I posted last. Unbelievable, I have been busy, busy, busy. My commercial project took a lot of time including another trip to Melbourne and Sydney and a quick stint to Brisbane. Lots of hours looking after the project covering all kinds of aspects. I also have done a few hours on the caravan once in a while. A long list of little things, I will eventually post about it and show some more pictures.
The most recent activity was putting some cables together for the motorised ball valve for the inlets and outlets of the water tanks. I have cut the cables to length and fitted the connectors to both ends. So far I have done about half the cables I need, some more valves for tanks, some for the heater units and some for the shower circulation system.
I also built a test unit today to test all the cables with an actual valve. This will also serve as tester for the actual valve units already fitted to the van. I had an issue with the control box some time ago and it was because I did not test every outlet thoroughly on the lab desk. I had 2 wires crossed of two outlets and it took me a while to find it. Now I make sure every pin and cable works at is supposed to work. Saves time at the end.
Each ball valve has five wires, two for the motor drive and three for the feedback lines. The motor lines drive the valve motors with reversed polarity. I use relays in the valve controllers to switch polarity of the output lines. The feedback is created by two switches , one for fully open and one for fully closed. One wire is connected to ground and the switches connect each feedback line to the ground wire.
I use five pin waterproof connectors for the valve cables. In the tester I connected the feedback lines to the minus side of two led lights as end position signals. I have done the same for the load sharing valves of the suspension.
All the cables I made tested ok and are ready to go into their designated place. The valve cables are not yet prepared yet. I have to install the other side of the five pin connectors, however I use two different brands of valves and the pin out (cable colours) are different for the two types. This needs a little care when fitting the pins into the connector cases.
Here is the reference to the valve control unit.