Date: Wed, 27 Jun 2001 23:47:01 -0700
Reply-To: Alistair Bell <albell@UVIC.CA>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Alistair Bell <albell@UVIC.CA>
Subject: Re: 130Amp alternator upgrade?
In-Reply-To: <AIEFIGCNNANNIHLNFBPEKEBLDIAA.vanagon@volkswagen.org>
Content-type: text/plain; charset="US-ASCII"
The "12 Volt Doctor's Practical Handbook for the boat's electrical system"
has a good discussion on external adjustable regulators.
Westies often become sailboats when on camping trips, ie. often have
subtantial current draw on battery when parked and infrequent use of engine
for recharging. What you want is for the alternator to recharge the battery
more quickly when the engine is on, fiddling with an adjustable voltage
regulator is one way of doing that, and is done on sailboats...
ahoy David B.!
also, if you have a non-stock (ie gel cell) battery...
charge cutoff V maintainance V equalization V
wet cell @ 80 F 14.4 13.5 16.5
wet cell @ 100 F 13.9 13.3 15.8
gel cell @ 80 F 14.4 13.8 NA
gel cell @ 100 F 14.1 13.8 NA
charge cutoff voltage = battery voltage at which heavy charging should be
stopped
maintainance voltage = voltage at which the battery can be maintained for
long periods of time without excessive water loss
equalization = controlled overcharge, done periodically to help mix up
electrolyte. Not to be done on sealed or gel cell batteries.
Replacing the cable from the alternator to the battery with something
beefier, cleaning contacts is the obvious first step.
Alistair
on 27/6/01 10:20 PM, David Marshall at vanagon@VOLKSWAGEN.ORG wrote:
> The Bosch distributor was telling me about an adjustable voltage regulator
> for the Bosch alternators - I think it could go up to 16V. The logic behind
> this is on some vehicle, like our vans and most Audis, there is a long run
> between the alternator and the battery. The battery wants to see 14.4V for
> charging but with the long cable run the I^2xR losses result in a smallish
> drop in voltage by the time it gets to the battery - by turning up the
> output of the alternator you can make it so there is 14.4V at the battery
> again. Anyhow ever try this?
>
> Another link I remember seeing is installing a Ford external voltage
> regulator in a Volvo (normally a Bosch alter with an internal reg) - I think
> this could successfully done in the Vanagon and the mounting of the voltage
> regulator would be at the battery so it could sense the voltage where it is
> needed.
