Date: Sat, 21 Aug 1999 00:54:53 -0400
Reply-To: "Joe L." <jliasse@TOAST.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: "Joe L." <jliasse@TOAST.NET>
Subject: Re: Which Voltmeter to use?
Content-Type: text/plain; charset="iso-8859-1"
"electronic overload protection" sounds to me like the METER is protected
from overload; if everything else melts down the meter will still be ok.
This is not to say "dont use it" but before you do further checking is
needed. Somewhere in the instructions or on the meter itself there should be
the number for "Input Impeadence". If this number is 10 meg ohms (sometimes
written as 10,000K Ohms) or higher you should be fine (the symbol for ohms
looks sort of like an upside-down "U").
If you cannot find this information anywhere on the meter or in the
instructions call the maker. If you cannot find out then you have a decision
to make. Either get another meter you KNOW is safe or take the chance of
popping something VERY expensive with the meter you have.
I plugged your meter into a couple of search engines to see what came
up. Nothing on your specific meter but I did find this:
A.W. Sperry Instruments, Inc., 245 Marcus Blvd., Hauppauge, NY 11788;
516-231-7050.
They should have a tech support department that can tell you what you
need to know.
----- Original Message -----
From: Thomas D. Hanlon <hanran.inc@prodigy.net>
To: Joe L. <jliasse@TOAST.NET>
Cc: <vanagon@GERRY.VANAGON.COM>
Sent: Friday, August 20, 1999 2:59 PM
Subject: Re: Which Voltmeter to use?
> Joe,
>
> Does a meter such as I have, the A.W. Sperry Model Dm-2a, described on the
> packaging as having "electronic overload protection, meet your criteria?
That
> is, does that term mean, to you, " approved for use on computer
> controlled-cars?"
>
> Features:
>
> UL Listed in US and Canadian Safety Standards
> limited one-year warranty
> ELECTRONIC OVERLOAD PROTECTION
> autorangin
> simple operation
> continuity buzzer
> rangehold button
> built-in test leads...
>
> Cost appx $30.00...Usual disclaimers apply
>
> Tom Hanlon
> Palm Springs, CA
> 84 Westfalia
>
> "Joe L." wrote:
>
> > Im no expert but one thing I DO know. If you are gonna mess around
with
> > any vehicle with a computer on it you MUST have a voltmeter with what is
> > known as a "High Input Impeadence" (10 megs or higher). This is
basically
> > how much of a load the meter itself puts on a circuit when you use it.
> > What you do when you use a voltmeter is sort of the same thing you
do
> > when you plug the toaster into the wall socket; you add the meter to
> > whatever curcuit you are testing and this increases the load on that
> > circuit. Plug in one too many toasters and you blow the fuse. "Plug in"
a
> > low impeadence voltmeter and you blow the computer! This is why you will
see
> > words like "Approved for use on Computer Controlled cars" on SOME
> > voltmeters but not on others.
> > Nowadays it is pretty easy and inexpensive to find a suitable one
> > (usually digital) but you cant just get whatever is cheapest at the
Radio
> > Shack.Sunpro puts out a deceint one ($40??) you can pick up at your
local
> > FLAPS.
> >
> > ----- Original Message -----
> > From: Jeff Gilbert <jeff_gilbert@PEOPLESOFT.COM>
> > To: <vanagon@GERRY.VANAGON.COM>
> > Sent: Thursday, August 19, 1999 12:26 PM
> > Subject: Which Voltmeter to use?
> >
> > > Hi,
> > >
> > > Im new to all this diagnosis stuff and was wondering if someone could
shed
> > > some light on what would be a good voltmeter to aid in the diagnosis
of a
> > > never ending, son of a bitch, fuel injection problem. Bently suggests
> > > using the VW meter...is this necessary, or will any good quality meter
do?
> > >
> > > Thanks,
> > >
> > > Jeff
>
>
>
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