Newbie's experience... so far

New user, ordered an IotaWatt after reading this thread https://forums.whirlpool.net.au/thread/3rpxj663 and doing some google searches and a lot of reading.
As a long term Smappee user I have been on the lookout for a device that will enable monitoring of power consumption by Circuit Breaker rather than the two balloons (Consumption and Solar) of the Smappee app.
We have 20 PV panels on the roof with Enphase Micros and an Envoy that feeds PVOutput. I am a retired assembler programmer with some Linux skills and have several Raspberry Pi media players around the house. IoTaWatt and Emoncms appeared to be in my skillset.
So, I ordered an IotaWatt Aussie bundle with extra CT clamps which arrived on the South Coast of New South Wales Australia 8 days later from scenic New Hampshire in the USA.
I had a spare phone charger and a quick solder job spliced the correct plug to an ancient 9v AC transformer and all plugged in and away it went. Setting WiFi was completed then calibrate the AC by comparing to a Baun Power Meter bought from Aldi.
Having read Tracking separate solar Feed In Tariff I put two CT clamps on the mains feed to the switchboard and a single clamp on the solar feed and proceeded to configure the three inputs and then the outputs.
I also configured an output for Consumption as follows
Consumption Watts = ((Abs_Main + Net_Main) ÷ 2) + Solar_Feed - ((Abs_Main - Net_Main) ÷ 2)
Quick aside to overeasy, Net_Main is self explanitory, but Abs_Main? What does the “Abs” stand for? Absolute? And did I get the Consumption calc right ?

A minor bump was that a second power meter, branded “Solar Inverters Power Meter” ( which I suspect is a re-branded WattMeter) read about 2v less than the Aldi meter - 2v in 240 is less than 1%, but which was more accurate? Calibrating IotaWatt voltage to the lower voltage brought it close to the Smappee readings.
Next step was to get Emoncms running on a Raspberry Pi 2b. Simply download and flash an SD card accoding to https://www.raspberrypi.org/documentation/installation/installing-images/README.md
Configuring IoTaWatt Setup/Web Server was straightforward and an Emoncms Service was created.
Next was onfiguring the Emoncms using this guide https://guide.openenergymonitor.org/applications/solar-pv/ . This worked and I now have the moving window power view of solar generation Vs site-consumption display on my laptop.
Next week we are getting another 10 PV panels installed on the roof and I’ll get the sparky to install CT consumption clamps for each of the circuit breakers in the switch box.
Is there a worked example with screen shots for this simple setup in the forum ? I couldn’t find one. The Emoncms guide assumes a degree of familiarity that I didn’t have which led to some frustration and I think that a step by step with screen shots integrating IoTaWatt would help the newbie.

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