Updates and future plans.

Prototyping board update:

   The 2.54mm pitch screw terminal block connectors arrived, as have the 12" 2x20 ribbon cable and new 5vdc relay card. re-wiring the relay card is done. F-F and F-M jumpers are on order as is a GPIO HAT for the Raspberry Pi. The screw terminals fit the header profile of the breakout modules and two standard headers for the ADS1115s remain.

A power connection has to be run from the array power lines (36vdc) to the relay card, to power the linear actuator (36vdc). I have been using the battery bank's 24vdc supply, however, that slows down the actuator's speed.

Connections between the Raspberry Pi's GPIO header and the breakout modules will be from the GPIO HAT using jumpers, screw terminals, wire and ribbon cable.

Current list of modules:
real time clock
8-channel multiplexor
analog to digital converters (ADS1115, PCF8591 multi-function)

Photo of the current state of the prototyping board:

The 5vdc relay card is on the left.
The buck converter is next to the relay card and will replace the Apple iPad power block as power supply.
The Raspberry Pi SoC (System on a Card) is in the middle. The RPi is a full fledged computer.
The PCF8591 is on the right.
Multiple ADS1115s will be placed on the far right.
The 8-channel multiplexor will be placed aboce the relay card, on top.
There is a temperature controlled relay, 20A, module that may be on the right.

The Temperature controlled relay module could be placed above the relay card and in the same  orientation. The multiplexor could be placed on the right and replace some of the ADS1115s.
There is no designated use for the temperature controlled relay card or the multiplexor.
They may be added later on, or left out.
The LCD panel voltmeter needs to be moved up to the prototyping board.

A 12vdc relay card arrived and will be kept for possible future use or resale.
Some consideration has to be made to implementing the plans for a dual-axis tracker and re-mounting of the array on an improved frame.

I need to double the number of batteries in the battery bank to optimize the MPPT controller's function. The controller limits current to 2A for each battery in the bank. This results in a mximum of 250w being drawn from the array. The array is capable of generating 580w.