alt switc
My voltage is a steady 13.8 so going back to my school electricity assuming
a constant load and constant voltage the amps should be constant as well.
My second ammeter on the bat + fat wire shows a consistent charge once the
starting energy has been recovered.
In any case I will follow your advice and measure V and A with a separate
instrument.
thanks
Will
William Daniell
LONGPORT
+1 786 878 0246
On Wed, May 13, 2020 at 9:25 AM Gilles Thesee <gilles@elixir-aircraft.com>
wrote:
> Le 13/05/2020 =C3- 14:52, William Daniell a =C3=A9crit :
>
>
> *I have a 912 turbo with a skyview.*
>
> *About once a flight my amps go up off the chart - 70a - ending up with
a
> red x on the screen (no sparks or smoke :-)). After which the instrumen
t
> comes alive and the amps reduce to normal 7-10 depending on the load. And
> remain normal thereafter.*
>
> *When the amps are climbing the reading can be "reset" by turning off the
> alternator and then turning it back in again.*
>
> *I have a hall effect sensor on the thick wire which charges the battery
> and this changes very little as on would expect.*
>
> *I asked the europa and the aeroelectric forums and dynon. Several peopl
e
> said they had similar events. So having checked the wiring i assumed
> that this was a dynon bug. *
> *AND ....I always understood that the alternator was unable to produce
> more than 18A hence people adding external alternator. But is thus a fai
r
> assumption?*
>
> *Could it be a faulty regulator?*
>
> Will,
>
> Understand your concern.
>
> I'd say an ammeter is not very useful as a *cockpit* instrument. An
> alternator is physically *incapable *of supplying more than its
> short-circuit current (21A for the Rotax).
>
> What counts is *voltage* : under 12V, no charging, above 13+ V, system is
> charging, above ~15V, overvoltage etc.
>
> I cannot help you on the Dynon, since I never installed or used one, and
> never bothered to read its manual.
>
>
> Nevertheless, anytime you have an odd looking *instrument indication*, th
e
> first thing to do is check what the *actual value* of the indicated
> parameter is.
>
> So the first thing to do is record or take note of the ship circuits
> voltage with an idependent instrument. If you don't have a panel voltmete
r,
> your VHF certainly provides a voltage indication. Otherwise you'll need a
> portable voltmeter or datalogger.
>
> Only then will come the time to make assumptions as to what actually
> occurs and what is at fault.
>
> FWIW,
> --
> Best regards,
> Gilles
> http://contrails.free.fr
> http://lapierre.skunkworks.free.fr
>
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