Another component I have been working on during the last days, apart from the plumbing I have done, is the unit to control the motorised ball valves for the heating elements as well as some valves installed with the water tanks.
The complete unit comprises two components, the relay component and the processor component. Above image shows the relay board with 16 relays driving 12 ball valves. The connectors are 5 pin plugs connecting each ball valve. Two wires drive the motor. Changing polarity changes the direction of the valve movement. The other 3 wires are used for the feedback signal. One is ground and the other two are the return signals when the valve is closed or open.
The relay unit is connected to the processor unit with two 25 pin cables. One cable is carrying the switching signals (16) and the other cable is connecting the feedback signals(24).
The unit comprises 12 connectors for one valve each. I need 2 of these units for all my valves in the van. Takes a while to put these together, has over 120 solder connections.