Battery Current draw

[N6722c]

A few items do not seem to be drawing the correct current.

(1) Fuel Pump (10A breaker) is drawing 11+ amps ( way too high)
(2) Strobes do not draw any current. They should draw a significant current.
(3) Beacon does not draw any current. Should draw a noticeable current,
(4) Cockpit/panel lighting draw no current.

With all switches off (except battery), there is a 2.2 A draw. What is causing this ?
Only items powered are the Clock and the Battery solenoid, and a few Status Warning Lights)
( 2.2A total may be reasonable, its a BIG solenoid !!)

Avionics, Turning on/off (with all radios ON) does not alter current draw.
==========
Running down the battery -- turn on lights etc !! (I'm bad )
Voltage drops .. LOVE the way the Fuel pump slows down as the voltage drops !!
But INCORRECTLY, Current draw remain CONSTANT as voltage goes from 24v down to 12 volts !

As voltage drops, say below 18 volts, tuning ON/OFF load should alter battery voltage.
There should be a quite a wide range of lower voltages, where the battery reaches a state, where turning on a load, takes the battery below the voltage needed to keep the battery solenoid energized, it turns off, load becomes zero, voltage rises, energizes the solenoid, draws current, voltage drops, solenoid drops out.. etc etc, and one hears the classic CLICK - CLICK - CLICK from solenoid. ( even more noticeable when trying the starter !!).
Turning everything OFF, waiting for the battery to "recover" , and then trying to start the engine again, can often result then in an engine start, without having to get a Jump start, or a new battery.

GETTING TOO DETAILED for a Simulation. ? I think not. It's almost there -- the simulation tools are in place (accusim ?), so why not go that extra step, and get it as realistic as possible.

In all fairness, this is what I expected from A2A in this C172R, and is what I thought would justified the $50 for "another" Cessna 172.


The actual current draws are difficult to obtain from normal documentation,
Maybe next time someone has access to a C172R, they can measure these items, and add them to the simulation.

If this stuff is going to be simulated (accusim ?), and is one of the big selling points for this aircraft, it may as well be done right, rather than wrong -- otherwise, the default C172 is starting to look quite acceptable !!

That being said, I congratulate A2A on this 172R, and the way they are supporting it, and responding to their customers.
No regrets ... and look forward to the corrections that should be coming in future Service packs.

Not Everyone (Anyone) can be PMDG, and it it all right the 1st time !! -- yes I'm joking !!

[some1 - A2A]

We'll check that, but that's not exactly what I'm seeing here, for example the avionics draw is here and it was based on the exact information from the maintenance manual (each avionics unit draws separately around 0.5A).

Not Everyone (Anyone) can be PMDG, and it it all right the 1st time !!

Ok, you have a deal. From now on we are releasing one airplane every 2 years.

[N6722c]

We'll check that, but that's not exactly what I'm seeing here, for example the avionics draw is here and it was based on the exact information from the maintenance manual (each avionics unit draws separately around 0.5A).

Not Everyone (Anyone) can be PMDG, and get it all right the 1st time !!

Ok, you have a deal. From now on we are releasing one airplane every 2 years.

LOL I was joking -- how many SPs did the last PMDG plane have, and it's still has issues

You fixed my crashing, and got me a test patch within 12 hours -- I call that OUTSTANDING .. certainly no complaints from me

[N6722c]

We'll check that, but that's not exactly what I'm seeing here, for example the avionics draw is here and it was based on the exact information from the maintenance manual (each avionics unit draws separately around 0.5A).

Testing Again, this is what I see.

(1) Fresh from full maintenance.
All Radios & GPS off. (note cannot turn off AP module)
(2) Turn on Battery >>>> Current draw 2.2A
(3) Turn on Avionics >>>> Current Draw 2.6A
(4) Turn on COM1/Nav 1 >>> Current Draw 3.1 A
(5) Turn on COM2/Nav2 .>>>> Current Draw 3.5A

Looking right so far

(6) Turn OFF Avionics >>>>> Current draw back to original 2.2A
(7) Turn on Avionics and all other Radios >>> Current 5.4 A

Looking GREAT !! ( feeling embarrassed now )

Mechanic must have fixed the issue, when it was in the maintenance hanger

I am sure it was STUCK at 2.2 amps, with Avionics on .. maybe some INIT issue, or something got locked up. But Avioics Current Draw is working now --

BUT ( and there is always a "but")

(a) BCN and Strobes do not add to Current Draw
(b) Neither do the 4 lighting controls.
(c) And Fuel Pump is drawing 11.2 A on a 10A Breaker switch.
I would guess at about 6-7 amps max ??











Geoff

[voth]

well it seems beacon and strobe does indeed not increase the load (but i don't know how much watts these things actually take)

but i cannot confirm your other findings. the battery pretty much behaves like i expected it to work.
thee avionics have their load - and voltage rises and drops with added or removing additional load.

but it was an interesting test - as i tried it in the dark it was really nice to see the flooding light extinguish while starting the engine.

i am using the stock battery (RG24-11M)

[Tigerclaw]

as i tried it in the dark it was really nice to see the flooding light extinguish while starting the engine.

You have GOT to be kidding me. The lights actually dim or go out when you engage the starter with a low battery?

Now THAT is incredible detail, WOW

[voth]

Now THAT is incredible detail, WOW

thats what i thought!

it is actually off and comes back with a short dim period. but you can just test on your own as i wouldn't say it is depending on the voltage.

[N6722c]

well it seems beacon and strobe does indeed not increase the load (but i don't know how much watts these things actually take)
(RG24-11M)

Strobes and beacon take a significant current. At least that of Nav lights, the strobes even more.
Newer LED lights be a lot less. Should be an easy thing to check, next time in the RL C172R.

[FernandoDiaz]

well it seems beacon and strobe does indeed not increase the load (but i don't know how much watts these things actually take)
(RG24-11M)

Strobes and beacon take a significant current. At least that of Nav led light, the strobes even more.
Newer LED lights be a lot less. Should be an easy thing to check, next time in the RL C172R.

Yes led lights consume much less current so becomes very affordable.. Even I am using these lights