The build relies on that old stalwart, the Arduino Uno, to run the show. It’s hooked up to a DS3231 real-time clock module so it can keep accurate time for long periods, as is befitting a clock.

It is equipped with 32 Inputs (16 x digital 4-30V, 8 x analog 0-10V, 4 x analog 0-5V, 4 x analog 4-20mA) and 20 Outputs (8 x relay 250V/5A, 2 x open-collector 30V/1A, 8 x analog 0-10V) and offers ...

Conversely, the comparator output and the connection to the Arduino’s analog converter (A0) are labeled nodes from the “Output and Labels” menu. The names are significant, including the spaces.