Date:         Sat, 5 Sep 2009 10:28:35 -0700
Reply-To:     mark drillock <mdrillock@COX.NET>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         mark drillock <mdrillock@COX.NET>
Subject:      Re: Run time to charge Aux battery
Comments: To: Bob Stevens <mtbiker62@GMAIL.COM>
In-Reply-To:  <586a66170909051011p59b2519cg69115b8b07cf52b6@mail.gmail.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed

Agreed, generalizing about the idle charging capabilities based on the
failure of a single charging system to work right is not valid. I have
charged my batteries at idle many times in various Vanagons. Maybe the
Bosch alternators are better at this than the Subaru ones but I doubt
it. I think the key is healthy wiring of a proper size.

If you measure the voltage at the alternator while idling and then turn
on the headlights, dash fan, etc you can judge easily enough how able
the alternator itself is of keeping up with the load. The voltage will
not drop much if it is keeping up. If you also measure at the battery
and see a much bigger drop, it is the wiring that is not keeping up.

Mark
with 2 electric only fridge Camper Vanagons only on alternator charging


Bob Stevens wrote:
> On Sat, Sep 5, 2009 at 10:42 AM, Kim Brennan <kimbrennan@mac.com> wrote:
>
>> It is probably folly to idle the engine expecting the alternator to
>> charge the batteries. I don't know what the idle speed is on the
>> zetec, but most engines are turning slowly enough that the alternator
>> is putting out minimum amps. In otherwords, just enough to keep the
>> engine running, but not enough to charge the battery.
>>
>
> This isn't true on my rig. I've been parked for 3 days and the kitchen panel
> light going into
> amber for "battery" level running everything it does, and when idling the
> engine for 20-30
> minutes that light returns to green WHILE THE FRIDGE/RADIO ARE RUNNING, and
> after
> another day the amber light level returns, while the fridge/radio are
> running. Idle is at 600rpm.
>
> I'm using the UB12220 wheel chair batteries (4) set up and have no
> electrical level monitoring
> gauges to actually tell me any specific information. I have a '90 Subaru 2.2
> motor with an SVX
> alternator (95 amp) in the system. I also have the 1315 separator in my main
> battery box.
> Vitrifrigo fridge.
>
> Bob Stevens
> '87 Syncro Westy
>