Sim/cockpit2/electrical/plugin bus load amps
This dataref contains an additional load (in amps) applied to each bus that is specified by plugins.
X-Plane will not reset this dataref during flight; if you want to share the dataref between multiple plugins, add your load and then subtract it out later. If you do not need to share the dataref (because your aircraft uses only one plugin), you can simply write to this dataref.
(The assumption is that this dataref will be used by plugins installed with the aircraft and not by global plugins.)