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S-A-A-2 Battery Charging Questions #battery

Bob M. 2020/08/31 11:21

I was given an S-A-A-2 unit. Specific documentation for this particular unit is basically non-existant.

I used the supplied micro-USB to USB charging cable with my cellphone's charger. Three very bright red LEDs on the back of the metal case lit up and a fourth was blinking. Shortly thereafter that fourth LED list up constantly. I presume these tell me the state of charge of the battery. Since these LEDs are on the back of the unit, I won't ever see them unless I pick the unit up and turn it over or get a reflection off the table.

How long should I charge the device?
Can it be overcharged?
Will it hurt to leave it plugged in and charging for more than 24 hours?
Do these LEDs really tell me anything useful, like a rough idea of the amount of run-time remaining?
If a USB cable is plugged in and the unit is turned on, does the battery charge while it's being used?

CT2FZI 2020/08/31 11:32


Have you checked the user manual and diagram for the SAA2?

Links on this group home page.

Also, in the files section, one can find relevant information.

Bob M. 2020/08/31 12:04

Yes. The only place I found "charg" was in the specifications for the current drain on the battery. NO information on charging is in the user manual posted in the Files section.

There seems to be lots of variations of the V2 design and the style of enclosure, positioning of external controls and indicators, etc. The schematic shows several red LEDs with no function next to them.

Isidro Berniol 2020/09/01 22:11

If you look to the schematic you can read out what charging chip is
used. Then do a search for this chip and you can find out what charging
characteristics this chip has.

It is a common rule for all Lio batteries not to be left for ever at
full charged level. This will cost lifetime.

The best level for storage is between 30 and 80 percent.

Don't let them deep discharge at all!

If you like to use the unit stationary you can remove the battery, or
let the battery discharge down to 3V one a month.

This prevents that the battery will kill itself because of constant
presence of full charge voltage.

Better let the battery work and charge the unit till full charged plus
some hours.



Am 31.08.2020 um 21:04 schrieb Bob M.:

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