Showing the power balance

Are the batteries charging right now, or draining? One number answers that: generation minus consumption. If it is positive, something is left over for the batteries. If it is negative, the base lives off its reserve.

Generation: right at the producers#

Power values really do add up, so Sum is right here. Without a match Sum returns 0 – a field that currently produces nothing and a field that does not exist look the same.

Consumption: measured behind the battery#

Consumption comes from the cable analyzer on the consumers' network, that is behind the battery or the area power control. There PowerRequired reports what lights, heaters and pumps demand together. Between producers and batteries the number would be useless, because the batteries register demand of their own there.

lbn gen GEN HASH("Generator") PowerGeneration Sum
lbn tmp PANEL HASH("Dach") Charge Sum
add generation gen tmp
lbn usage CABLE HASH("Verbraucher") PowerRequired Average
sub balance generation usage

The sign in colour#

sgn returns −1, 0 or 1. Two select turn that into the colour:

sgn tmp balance
select colour tmp Color.Green Color.Yellow   # not 0: green first
sltz tmp balance
select colour tmp Color.Red colour           # negative: red

The display#

With Mode Power the display appends a W. It shows negative numbers with a minus – together with the red colour you see right away that the base is living off the battery.