The voltage gauge should read 14-14.8 volts when the car is running 
down the highway and the altenator is working properly..

The ammmeter (measures) the rate of electricity (Current) generation. 
and the reading depends on how the gauge is hooked up.
If it is reading the altenator total output the readings will be higher 
than  if it is reading how much the charging system is feeding the battery
without the electricity it takes to run the car.  With the second hookup  
it should drop to near zero after the battery charges up.  If the battery
is old and tired, with this setup it could read some amps charging all the 
time.  
  Ammeters were on cars until the 80's.  Voltmeters are easier to put a 
green/red warning band on than ampmeters.  

Chuck & Peggy Paras <pcparas@erols.com>  May 2001



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You can test for a battery drain by loosening the negative battery 
cable and removing it slowly.  Any spark indicates a drain.
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If you're losing charge  over night, your battery has a drain on it.  To 
find the problem, disconnect the negative terminal of the battery and 
connect a test light ( 12v bulb with wires tapes to + / - ) in series 
( between the Neg battery post and cable to ground) .  If there's a 
slight drain, the bulb should illuminate, commensurate with the amount of 
drain. Place the bulb in an obvious place and go under the dash, removing 
one by one, the fuses.  When the light goes out, you've found the problem 
circuit
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