RE: (ET) charger

["Bob Murcek" <rmurcek geisinger edu>]

Larry,
The transformer in the charger is ferroresonant for voltage stability, 
right?  What's your take on why GE went to that extra expense?

>>> "Elie, Larry (L.D.)" <lelie ford com> 4/28/2003 10:51:02 AM >>>
Engineering is basically the art of compromise.
 
GE knew that fast charging was a selling point.  The charger they designed 
was OVER 1000W (it varies with how low the batteries are) because most 
people in 1970 had 15 Amp outlets.  The timer is all there is... BUT... 
remember, this is not a constant-current charger.  Nor is it even really 
constant voltage, because the load is a major part of the circuit.  The 
current is the limiting factor with low batteries, but eventually as the 
voltage goes to 42 or 44V, the current going into each battery has 
dropped, and the drain at the 120V outlet has gone down from 1000W.  You 
can check this with a Hall-Effect current meter at the batteries, and at 
your plug.
 
It isn't bad for the application, and very good for a 1970 'cheap fix'.
 
Larry Elie
 
-----Original Message-----
From: Jeremy [mailto:nagidog starband net] 
Sent: Sunday, April 27, 2003 3:28 PM
To: elec trak yahoo group
Subject: (ET) charger


I finally got my e-12 in working order and just mowed about an acre of 
hilly, very bumpy ground.  It did great, really a tough machine.  I have 
noticed that the charger really sucks the juice, about a 1000 watts when 
charging.  This seems great if you just want a quick charge and get back 
to mowing, but must be very hard on the batteries and is too much of a 
load for my solar system. . . I can do it, but would bring down my 
available solar power 20% for just one hour of charging.  Spread over time 
the load is not to big for my solar.  I think a DC to DC converter putting 
out 200 or 300 watts would charge more efficiently and put less strain on 
my solar system.  Also, my charging switch-dial has letters from a to G on 
it, but I have not noticed a difference in amperage depending on where the 
dial is set.  Is this dial strictly a timer.  What is the preferred method 
of charging using the onboard charger.  Short spurts over time, one big 
long charge.  Basically looking for the !
 low down on charging technique.
 
Jeremy