Re: (ET) Re: 48v E-trac ??

["MR23 \(Christopher M. Meier, Mpls, MN\)" <mr23 mn rr com>]

There is probably some info on this in the archives.  But briefly,
those that have upped to 48v have used PWM controllers for
both the drive motor, and for the PTO, and a DC/DC for the
headlights and lift.

----- Original Message ----- 
From: "Jim Coate" <jbc coate org>
To: <daveb seanet com>; "Elec-Trak List" <elec-trak cosmos phy tufts edu>
Sent: Friday, July 06, 2001 11:28 PM
Subject: (ET) Re: 48v E-trac ??


> daveb seanet com wrote:
> > Has anyone heard of anyone converting the E-trac to a 48volts by
> > using 6 8v batteries??
> 
> I've thought about this, but ruled it out. The drive motor could
> probably take it, giving a little more "performance" (9 mph instead of 7
> mph top speed??).
> 
> However, everything else would run into problems. The 12 volt tap for
> the headlights would now be 16 volts... nice bright lights until they
> burn out. The 18 volt lift would be at 24 volts... maybe it would
> actually have some oomph, until it also burned up.
> 
> All the accessories would also now be running at 48 volts. I think that
> the snow blower and tiller motors are series or sep-ex wound, so could
> take the extra voltage ok, but the higher operating speeds may give
> weird results. The mowing deck motors are permanent magnet and could
> well be damaged by the higher voltage, and again the higher speed might
> make for strange cutting results.
> 
> Finally there are all the control circuits which might not take the
> extra power.. and if you ever wanted to charge off a regular outlet,
> you'd need a new charger.
> 
> Sorry to be such a bummer, but the practical, and admittedly
> inefficient, solution would be to run the wind power through a 120 volt
> sine wave AC invertor and then plug in your regular 36 volt ET charger.
> Or if you are really lucky you can find some sort of appropriate dc/dc
> -- Rich Rudman is working on a new charger that may take DC inputs, but
> I think it is only for higher voltages of on-road EV's.
> 
> 
> PS A wind system designed for 48 volts batteries probably puts out close
> to 60 volts peak, so would need to reduce it a fair amount to charge a
> 36 volt pack.
> 
> _________
> Jim Coate
> 1992 Chevy S-10
> 1970s Elec-Trak E20
> http://www.eeevee.com