Value of Simvar ELECTRICAL TOTAL LOAD AMPS is negative?

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1

The value of the simvar ELECTRICAL TOTAL LOAD AMPS shows a negative value - shouldn’t this be positive?

John

2

Probably Charging at this stage… Turn off the Alternator or Gens to see a positive load.

3

I think this one confuses a lot of people, including Asobo.

ie The C172 Steam Gauge AMMETER in RL is showing the the discharge current from the battery.
If it is a Positive value, it means that the battery is being charged.
If it is a Negative value, it means that current is being drawn out of the battery, and the battery will eventually go flat !!

So, in the C172 it acts like the old Ammeters in a car…, + is GOOD , - is heading for a flat battery (BAD).

The C172 Classic Steam Gauge has the Ammeter go more POSITIVE, the more items you turn on, so it is showing LOAD, as opposed to battery Charging/discharging.

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4

Thanks for the reply. There are two distinct simvars:
ELECTRICAL TOTAL LOAD AMPS
ELECTICAL BATTERY LOAD
Looking at these in the C172, spawned on a runway with the engines started, these have the following values:
ELECTRICAL TOTAL LOAD AMPS= 8.27663708
ELECTICAL BATTERY LOAD = -8.27663708
which then gradually decrease/increase over time:
482250 SimRead: 2824=“ELECTRICAL TOTAL LOAD AMPS”
FLT64: 8.269780159
482281 SimRead: 282C=“ELECTRICAL BATTERY LOAD”
FLT64: -8.269780159
482328 SimRead: 2824=“ELECTRICAL TOTAL LOAD AMPS”
FLT64: 8.26249504089
482359 SimRead: 282C=“ELECTRICAL BATTERY LOAD”
FLT64: -8.26249504089
…etc
This seems to be ok and as expected.
However, I was originally looking at the Just Flight PA28 which seems to behave differently. This has a negative value for the total load amps as well as the battery load:
ELECTRICAL TOTAL LOAD AMPS = -50.644909
ELECTICAL BATTERY LOAD = -49.355091
This causes an issue if using the variable to drive an external gauge, as the PA28 ammeter has a range of 0 - 70 amps. It will need to be reversed.

Thanks,

John

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5

I ended up fixing the issue in the C172 Steam gauge Ammeter gauge, with a simple MOD file to reverse the Min & Max values of the gauge — one of the xml or cfg files.
Long time ago, cannot remember exactly what or where, but now have just got use to it being correct, and do not think about it as an issue anymore.

The Carenado M20R had a similar AMMETER issue, displaying Current X 10, and to one decimal point accuracy. ( Should be NOT x10, and just an integer)

I reported it to them, got no reply, and do not think they ever fixed it …
(unfortunately — nothing unexpected ! )

6

Ok, thanks - think this is the relevant post on this where you explained in more detail:
Wrong ammeter readings on Cessna 172SP classic
Just for completeness!
Regards,
John