Date: Fri, 21 Aug 2009 11:29:44 -0700
Reply-To: Rocket J Squirrel <camping.elliott@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Rocket J Squirrel <camping.elliott@GMAIL.COM>
Subject: Re: Engine electrical power requirements?
In-Reply-To: <1EB093D2-2F9A-40C6-B035-87082EDDF824@mac.com>
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Oh right -- the rad fan. I'm interested in power requirement when idling.
Don anecdotes* that he drove 400 mi on battery alone, so as you say, the
engine doesn't need a lot of juice to run.
===========
* Anything can be verbed.
--
Mike "Rocket J Squirrel" Elliott
84 Westfalia: Mellow Yellow ("The Electrical Banana")
74 Utility Trailer. Ladybug Trailer, Inc., San Juan Capistrano
Bend, OR
KG6RCR
On 8/21/2009 9:37 AM Kim Brennan wrote:
> A gas engine uses very little electrical power. Most of the amps are for
> other things, such as fans, radios, lights. A standard battery will run
> an engine for a long while.
>
> A diesel engine will go even further, as once it is running, it doesn't
> use practically any electrical power.
>
> On Aug 21, 2009, at 11:01 AM, Rocket J Squirrel wrote:
>
>> Yeah, well, I suppose the only persons who actually /need/ to know the
>> power draw of the engine alone would be those whose alternator failed and
>> they were looking at getting home on the battery and thinking, ". . .
>> okay
>> this is a 40Ah battery . . . I wonder how long it can power the engine?"
>>
>> That would be the ECU, fuel pump, ignition bits (coil und so weiter),
>> various senders and sensors stuff; and not counting headlights, radio,
>> etc.
>>
>> My interest is really on what your 90A Bosch alternator has left over
>> after taking care of the engine.
>>
>> I recall that the engine in my (now sold) 71 aircooled baywindow could
>> drain a battery pretty quickly and all it needed for power was for
>> ignition. No ECU, the fuel pump is mechanical, there's not even a temp
>> sender.
>>
>> Anyway, Mark Drillock provides the method to measure the numbers I
>> need. I
>> guess my in-depth article on aux battery charging -- which includes
>> excellent calculations of wire sizes based on available power from such
>> sources as your starter battery and alternator and takes into account
>> such
>> subtle matters such as internal resistance of typical lead-acid
>> batteries,
>> and which is intended to provide worst-case scenario for wire diameters
>> and relay contact ratings, will just have to wait.
>>
>> Simply a tragedy -- a tragedy, I tell you!
>>
>> --
>> Mike "Rocket J Squirrel" Elliott
>> 84 Westfalia: Mellow Yellow ("The Electrical Banana")
>> 74 Utility Trailer. Ladybug Trailer, Inc., San Juan Capistrano
>> Bend, OR
>> KG6RCR
>>
>>
>>
>> On 8/21/2009 5:50 AM Richard A Jones wrote:
>>
>>>> I am hopin' this is some bit of information that is commonly known.
>>>
>>> I asked the same question a couple of years ago and got nowhere,
>>> so I'd say "it is commonly known that it is not commonly known...."
>>>
>>> Richard
>>>
>
>
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