DeTomaso Mailing List: November 99, Message #330

 In a message dated 12-Nov-99 3:08:47 AM Eastern Standard Time, 
chelini@earthlink.net writes:
 
 <<   If you have a voltmeter, set the scale to a low range and place the
  leads across the fuse (not to ground) with the circuit operational. If
  there is any voltage indicated across the metal brackets at each end of
  the fuse, you have a resistance problem. Hope this helps, Al.
   >>
 
 Mary... et al
 
 As an addition to Al's excellent analysis:
 
 
 When you measure the voltage between the fuse holder tabs... you are 
including the contact resistance of the mechanical assembly (fuse holder tab 
to fuse ) ...and also the resistance of the fuse itself.
 
 The voltage measured must be close to ZERO with the circuit operational.
 
 Depending on the current flow etc   "CLOSE TO ZERO"  could be almost 
anything...  but in the normal auto circuit.. you should see less than a 
TENTH OF A VOLT
 (waiting for Flames from Dave D, Al et others).
 
 The bottom line... keep the fuse tabs/fingers as clean as possible as the 
corossion
 that occurs on the copper surface (the green crap) is just a resistor!  And 
the resistance will increase, over time, i.e. MORE GREEN!
 
 When the resistance in the circuit (fuse + fuse tab) goes up... there is an 
increase of heat developed at that GREEN point.... the heat will flow toward 
the fuse... and may eventually cause a thermal failure.  The solder in the 
fuse actually melts ( ! )
 and the fuse element separates from the end cap inside the glass!  OPEN FUSE 
 DEAD CIRCUIT!  Don't ask me how I know this  :-)
 
 And for you guys that are not doing so... get the GLASS GBC replacement fuses
 made by BUSS... available at Napa... Pep Boys... Discount Auto... Auto Zone 
etc...
 Go for it... only a FEW $$...
 
 After you  pull (and s**t can) the ceramic jobees... clean the tabs so they 
are nice and shiny and put a bit of tension on them to bend them towards the 
center of the fuse location.  Don't get over anxious or break the tabs!  Now 
that you have "pre-tensioned" the tabs... pop the nice glass fuse 
replacements in and you are good to go!
 
 If you are so inclined... fire up the kitty... turn on everything... and 
measure  the voltage across each each fuse assembly (the fuse and the tabs).  
File this away... or put it in the glove box with your meter for future 
reference  You do have a meter in the glove box don't you?  $19.95 at The 
Shack!
 


 WAIT... one more thing...Since VW knows these ceramic jobees...Maybe Cal 
needs them for his 2300 pound VW drop in!!!  Retain the old fuses momentarily 
awaiting word from Cal!
 
 (I couldn't resist) !!!    :-))
 

 
 DonM in MIami    seen some melted fuses in my day
 XOTICAT
 71 Yellow Euro pushbutton #1158
 
 www.WildRides.com/panpage/page50.htm
 
 PanteraDon@aol.com