Have finished programming and putting together two more electronic components, however not yet in boxes. I am waiting for some larger boxes to take the 16 relay board. Both components are connected to the CAN bus and use similar coding. The 16 relays are used for 5 latching relays in the main switch board. Five groups of 3 relays, 2 to create the direction polarity for the coil and a power relay to actually switch on the 12V to activate the latching coil. The power is only on for a short time just enough to create the impulse required to switch the 250V relay either on or off. I also can connect up to 5 temperature sensors. Two are used for the fridge cabinet to control fans for sufficient airflow behind the fridge.
The second unit is used to control the contactor for the solar panels. The contactor is also a latching relay with switched polarity for off/on. Instead of an external relay card I use a relay shield for the Arduino with 4 relays or which 3 are used in the same way as a single group in the 16 relay board. This unit also can connect 5 temperature sensors. I will connect the 5 sensors in the fuse boxes to this unit.
I extended my test panel program for these two units to be tested in my test field. Coding and test is complete. I now need to put these two components into a box. The same code is used for a valve controller. The only difference is timing of the on phases because the motorised ball valves need longer to open and close. The valves also have two feedback signals, one for open and one for closed. These signals are connected to the IO extender I use to control the 16 relay board. I have 10 input signals available for the feedback signals of 5 valves. I will need 4 of these boxes for up to 20 valves.