When is the battery "dead" in an ARC 4 ?

When is the battery \"dead\" in an ARC 4 ?

I am on my first battery with my ARC 4.
I just received it last week.
After using it today for about 15 minutes on level 8 it would then not go to full brightness.
After removing the battery to check the voltage (2.89 no load) and replacing it, it now will now still go to full power.
Does anyone know at what point a battery is more or less "used up" in an ARC 4 ?? (voltage with no load).

Glenn

Re: When is the battery \"dead\" in an ARC 4 ?

It depends on the battery type. You really can't go by no-load voltage. Basically level 1 stops working when the battery is about 70% used, level 2 stops working at around 80%, level 3 at 85%, etc, or something like that (some calculations are in a thread of a few weeks ago). By the time level 6 stops, the battery is around 95% used. The long reserve is deliberate, so you have plenty of warning to conserve battery power if you don't have a spare handy.

Re: When is the battery \"dead\" in an ARC 4 ?

The Arc4 needs 2.0 volts to power-up, however if it's already lit, it will run the cell down much lower than that.

Re: When is the battery \"dead\" in an ARC 4 ?

2.89 no load on most batteries (several hours after the last use) is pretty low; 2.9 no load is when Surefire says their lights will drop below specified lumens, and that's been my experience. Probably pretty much the same on Arc4, although the temperature cut-off can make it hard to tell. Also, a battery left alone for over a day will give a high no load read, but it disappears very quickly with use.

I am no expert, just an observer. . . .

carmel

carmel

Re: When is the battery \"dead\" in an ARC 4 ?

Also, Glenn, I cannot believe that 15 minutes at level 8 would put a decent battery in a position where it could not function on level 1. There's got to be something else going on there.....

carmel

Re: When is the battery \"dead\" in an ARC 4 ?

Thanks for the replies.
Any info that I can get will be helpful.

paulr: Thanks for the info that the ARC 4 also has sort of a built in battery checker. The ARC 4 looks more useful all the time.

carmel: The 15 minutes on level 8 was AFTER using, setting it up, and using it intermittently for about a week.
It was only IMMEDIATELY after that use that it would not "surge". That is also when I took the unloaded volt reading.
It is working fine on the same battery now and will go to surge (level one).

Glenn