First of all..... we don't think in terms of wattage. Amperage is the primary reference for power.
To my knowledge, there are no charts listing power usage. That is very arbitrary. Will every fuel pump draw the same current, every navigation receiver, every light???
You would have to break into a system to measure current draw, either directly or with an
Amp Clamp
.
A circuit breaker's rating and wire gauge would be your only guide to how much (approximate) power a system is pulling.
