396xt ok to run wall power after battery is charged?

[tampatracker]

Just got the 396xt, what a nice piece of engineering. I know there is a charging circuit, but I just want to make sure that if I hook it up to the wall, (or the cigarette lighter adapter for the car), that I'm not doing damage to either the radio or the batteries after batteries have been fully charged. I'd like to save the juice on the batteries for when I need it.

 

[spooney]

The charging circuit is disabled when you move the switch inside the battery compartment to alkaline. It will say Charger Off on the display.

 

[fmalloy]

The charging circuit is disabled when you move the switch inside the battery compartment to alkaline. It will say Charger Off on the display.

This doesn't really answer the question.

I have a 346XT. I believe when you start charging, it does a 14-hour cycle of charging. When complete, it says "Charge Complete", and I assume it stops charging. I have the following questions:

- At this point, is the scanner effectively running off the AC supply?

- If you unplug the AC adapter for a few seconds and plug it back in, does it start another 14-hour session, even for fully charged batteries, or does it sense the full battery and not do a charge cycle?

- If you unplug the AC adapter and partially use the batteries, when you plug it back in does it do a full 14-hour charge?

Basically, we want to know if the charger is at all intelligent, or if we should run the batteries all the way down before plugging in the adapter. The online User Guide does not give any details. I am not very familiar with NiMH - I use Li-Ion which has (actually requires) intelligent chargers.

I have also heard recommendations to only charge batteries in external chargers.

 

[UPMan]

At that point, the scanner is running off of the AC supply.

If you cycle AC power, the charge restarts. (This actually applies to both of your last questions.)

You can adjust the charge time to be from 1-16 hours per cycle.

It is impossible to safely do "intelligent" charging on NiMH in series. The cells need to be charged individually, preferably at a .5C-1C rate in order to detect a complete charge. It isn't desireable to have 2+ amps pumping into the scanner.

At the charge rate used (<.1C with the supplied batteries), most overcharge is dissipated as heat but chronic overcharging at this rate will result in a marginably detectable reduction in cycle life.

 

[tampatracker]

Thank you UPMan, that thoroughly answers the question. Appreciate your taking the time, John.

 

[berksguy]

I'm thinking about getting a BC346XT. So after reading this thread is the short answer that you should always let the batteries run down ?

 

[UPMan]

That would be best. Or set the charge time to a shorter period. Or charge externally. Or (do what I do), don't worry about it too much.

 

[berksguy]

That would be best. Or set the charge time to a shorter period. Or charge externally. Or (do what I do), don't worry about it too much.

thanks for the answer.. i'm plenty worried..still didnt decide what to buy But thats for another thread. But leaning towards this one now.

 

[CopyThat]

Doe Less Charge Time Make Batteries Hotter

Upman mentioned you can set the charge time from 1-16 hours when using the scanner to recharge the batteries. My Question is "If I set the recharge time from say 14 hours down to 8 hours" will that shorter time make the batteries hotter, or is it simply "Less time charged, less time you have to scan"

I have not got an external charger yet, and do not want my scanner to get too hot, so I have been leaving it at 14 hours for the charge time. But if 8 or 9 hour charge time will not heat them up vs. the 14 hour charge I would prefer that.

Thanks in advance.

 

[tampatracker]

As I understood it, the shorter charging time is not compensated for by an increased amount of juice flowing in to make up for that shorter time span. I believe it is "Less time charged, less time to scan." I got an external Radio Shack charger for like $10.00 to experiment with the batteries, charging times, ect. It says it's a 4-6 hour charger, and apparently delivers a full charge to 4 batteries in that time.