Message: 2
Date: Fri, 3 Nov 2006 20:37:19 -0500
From: David C Robie <mycroftxx1 juno com>
Subject: Re: (ET) 48v electrac
To: callahanrc hotmail com
Cc: elec-trak cosmos5 phy tufts edu
Message-ID: <20061103 212635 -349601 2 mycroftxx1 juno com>
Content-Type: text/plain
But I still wouldn't want to give an overvoltage, thus
overcurrent, to a
30+ yr old machine full of relays. Am aware of 8V, some use them in
fullsize EV conversions where pack space is limited. With those,
miles
per charge (assuming lead acid) is in proportion to battery
weight. It's
a tradeoff.
I can not see the need of more HP in a GE/WH, especially with
the
bigtime hills on my property proving that what power they got is
sufficient. Even a GE12 PM motor is sufficient here, if you shift the
tranny down to climb. a 16 with a field motor don't need that tranny
shift, just get into a field speed.
Another reason besides old parts;
More E will naturally force more RPM. That would force the flyball
speed
governor inside the motor to limit the rpm with light loading,
therefore
working all the time and defeating the 'more power with more voltage'
thought. That thing is not particularly a long lived sturdy part and
when these flyball governors cease function, balls usually fly off em
and get caught inside the motor locking it up. Have done 2 of em.
Luckily with both, there was no commutator or winding damage. On one,
there was a lot of magnet chipping but she worked all right when
cleaned
up.
The fix is to remove the blasted thing completely, all parts of it,
and
short it's wires. Only thing you lose is the power pulse switch
function
(which was never much good anyway) and RPM limiting in case the belt
breaks.
Dave
Weymouth MA
On Fri, 03 Nov 2006 09:20:06 -0500 "Matthew callahan"
<callahanrc hotmail com> writes:
Not necessarily, you could get trojan T-890's or something like
those. They
are 8 volt batteries with four cells instead of three, but the same
size as
a T-105 6V battery. So you wouldnt have to pack a extra two
batteries, and
have more HP, but range should be about the same in terms of lead
weight.
The Electric Ox is a 48V tractor, and i assume they use the 8V
batteries.
Some golf carts are now using the T-890's at 48 volts instead of 36,
but
retain the same battery tray design and set-up.
Matt