Braun Electric Toothbrush Charger Hack
Having used the Braun Oral B electric toothbrush for many years, I was disappointed to find that the design of the induction charger base has changed on the latest equipment.
There is a slot on the back of the base of the old charger to remove the excess cable and the stand for the wall
But the new charger base is small and can only be placed on a level flat surface.
This is much more convenient than the old base I installed next to the bathroom shaver socket.
A quick email to P & G did not reveal any technical/electrical differences.
So I decided to do some electrical measurements on the old and new chargers.
Because these are inductive chargers, it is not possible to measure the voltage and current directly, so I used ten turns \"search coil\" and multiple turns
Instrument for comparison amps-
Turn the output from the charger base.
See next> The original \"search coil\" I \'ve tried, the white coil shown above is taken out of an abandoned RFID tag.
When these results show that the output is roughly the same, I repeated the test using a coil taken out of the waste oral toothbrush. (
Brown coil shown above. )
This coil has dozens of turns, so the reading is higher, but it is confirmed that the output of the old charger at 110 V is about 50% higher than the new charger at 230 V :-
Old charger model 4728 :-
/C 460mA S/C (White coil)
110V 410mV O/C 290mA S/C (White coil)
110V12V O/C 75mA S/C (Brown coil)
New charger model 3757 :-
O/C 170 mA S/C v280mv (White coil)230V8. 7V O/C45mA S/C(Brown coil)
While the output of the old charger at 110 V is about 50% higher than the new charger at 230 V, I decided they were close enough and there should be no difference.
The charging control circuit inside the toothbrush should keep the charging current in an acceptable range, as the NiCd and NiMH batteries are very tolerant in terms of charging requirements.
So I modified the \"faucet\" of the old charger base by installing the toothbrush to the same shape as the new charger \".
I was a little worried that I might break through the plastic and expose the metal core, but that didn\'t happen.
The toothbrush fits perfectly now, charges perfectly, and is against the wall --
Install as needed.
Polished with fine wet-and-
Dry grinding and metal polishing should restore the finish of the tap when I have a chance. . . . .