As previously posted , a bat fault message is indicative of the bcl seeing a thermal runaway or short with the battery , at this point the battery is disconnected from the bat bus .
Although this situation is not good I can see and assumed no other effect on the electrical system apart from the likely imminent failure of the hot bat buss pertaining to the failing battery.
I briefly pointed out that the hot bat bus feeds back up dc to elacs and secs and adirus .
Considering superpilots question re anti ice and v25 cfm I dismissed the anti ice scenario due to the assumption the power had not failed to the valves so therefore no change there,
I gave some thought to the way the different eec handled the loss of px or temp inputs causing the engine to be shall we say less frugal ..
but..
FUEL CONSUMPT INCRSD
This message is triggered when the failure (or combination of failures) affects the nominal aerodynamic characteristics of the aircraft.
That statement alludes to an aerodynamic change as the root cause,,
FMS PRED UNRELIABLE
Disregard FMS fuel predictions and refer to QRH/PER-B Fuel Penalty Factors Tables in order to find the applicable Fuel Penalty Factor.
This and the article I posted refer to the fms prediction being calculated by fixed values and not actuality's , basically stated,, rubbish in rubbish out.
Lurkio I felt your statement in answer 2 summed it all up really well ,, ie have a look see if anything is failed and apply any factors from the fpf tables ,
As to why .......
I am very very surprised to hear that loss of a hot battery bus will lead to double elac roll loss but if that really is an airbus reply so be it , personally I would have thought double elac roll loss would have concentrated your minds a lot more on other matters than working out a change in fuel consumption .
One thing I feel is correct however is it will be an airbus answer
I have looked through all the manuals and bulletins I have and can find not much about it , But if anyone want to point me in any direction not considered I can only try , it is very difficult to make a qualified statement on any components behaviour with a partial failure as quoted and subsequent circuit effects and I don't think the answer will be in any maintenance manual troubleshooting manual etc etc ..
All very interesting though,,