So, I kicked myself for being so lazy ;), then went ahead and took the
alternator off and took it apart. Checked the diodes while I was at it -
0.489V drop across each one, nicely matched set - as well as the stator
and rotor resistance. Tightened all the internal screws, too. Turns out
that the regulator in there sits across the negative side of the field
coil, so I just tapped that off and led a wire out of the back of the
case so I could full-field it whenever I wanted to (and can now install
an external regulator, too.) Then, I put it all back together (woo-hoo,
no extra parts left over!) and fired it up. No change in the results, of
course, but I graphed the output over the first hour:
Initial resting voltage: 12.04V
Charging with a 105A alternator/internal regulator
Time Amps Volts
0 102 13.82
0.5 85 13.88
1 78 13.91
2 76 13.95
3 74 13.95
4 73 13.96
5 72 13.96
10 68 13.98
15 66 14.01
20 63 14.04
25 59 14.06
30 54 14.10
35 47 14.14
40 40 14.18
45 34 14.22
50 29 14.26
55 24 14.30
60 20 14.32
Since the curve normalizes within a minute or so of start-up, we can
do an essentially straight-line extrapolation: (80 - 20) / 2 + 20, for
an average charge current of ~50A. So, in an hour of running, I took it
from about 60% DoD to about 10% DoD, which says that I've got a 100AH
bank. What I'm supposed to have, according to Deka, is 396AH (2 x 198AH.)
[sigh] It may well be time to contact Deka and find out what I can do to
test these. At 129 lbs apiece, I'm *not* looking forward to having to
lug them around.
--
Ben Okopnik
-=-=-=-=-=-
No comments:
Post a Comment