BATTERY LIFE IN AN ARC 4+

Using "flash amps" to test the battery in my ARC 4+ (second) I came up with the
following data.
The light was used intermittently at about the same amount of use throughout the period.
This is not very scientific but may still be interesting.

10.5 NEW
9.8 at 13 days
9.1 at 19 days
7.5 at 23 days
6.9 at 26 days
5.1 at 30 days

At the 5.1 "flash amps" (and 2.68V unloaded) the ARC 4+ would not surge to full power.
At this point I replaced the battery
At the increasingly faster rate of discharge I figured that I had used most of
the energy in the battery.

Conclusion (just my guess):
The battery declines slowly at first and then declines at an ever increasing rate.
This is probably due to the regulated ARC 4+ pulling more from the battery as
it declines in order to keep the brightness constant.
An unregulated light would probably have "needed" the battery replaced at
about the 9.1 - 7.5 amp level (or sooner) due to decreasing brightness.
I definitely prefer the regulation. That is my main reason for buying the ARC 4+
That...............and the selection of power levels.

Again......this is not scientific but, may still be informative.

Glenn

Your specs seem accurate and I believe the batteries should show an increasing rate of discharge at constant brightness.

That's the way old fuel gauges in cars used to work. You could drive around forever on the first quarter tank and then it would nose dive to empty.

[ QUOTE ]
jayflash said:
That's the way old fuel gauges in cars used to work. You could drive around forever on the first quarter tank and then it would nose dive to empty.

[/ QUOTE ]Jayflash, I remember those days! BTW, I think you've dated yourself! /ubbthreads/images/graemlins/wink2.gif