How to get 12V from this NOKIA AC-15E charger ?

[mister_rf]

@hussien55

I think that’s the charger circuit diagram...

In order to modify the output voltage you need to do more tests/experiments, and that’s a very risky situation, in any moment you may complete ruin the whole circuit.
So, if you want to try, start by replacing the zener diode by a new one, this time voltage rated value up to 2.4 times bigger than the original one. Anyway, I don’t have all details about this charger so maybe it’s not possible to get an increase to 12V output without major changes of the transformer secondary coil.

Still same precaution to be considered for the output filter capacitor, this must be rated at minimum 16V.

 

[jiripolivka]

@mister_rf is having Original charger ...

and @hussien55 is havng "fake" charger . it is not original nokia charger let alone the mentioned one/... first get original charger bro ..

I am sorry you have suffered so much loss! The problem is that a Nokia charger is designed to supply 5 VDC, some 300 mA.
Reducing the voltage is easy, by adding a resistor and a Zener, or an IC regulator suitable for the task.
As there are so many cheap AC to DC wall plug-in power supplies, I will simply go to a flea market and buy a cheap working 12 VDC power supply. There are also low-cost regulated AC to 12 V DC versions.
If you really burned a 100 V capacitor by not knowing the importance of its polarity, I would recommend first to read more about power-supply design and basic components. Without such basic knowledge you will rather make smoke and cause damage.
Power supplies look easy but a good one needs some knowledge.

Good luck!

 

[khankll]

I am sorry you have suffered so much loss! The problem is that a Nokia charger is designed to supply 5 VDC, some 300 mA.
Reducing the voltage is easy, by adding a resistor and a Zener, or an IC regulator suitable for the task.
As there are so many cheap AC to DC wall plug-in power supplies, I will simply go to a flea market and buy a cheap working 12 VDC power supply. There are also low-cost regulated AC to 12 V DC versions.
If you really burned a 100 V capacitor by not knowing the importance of its polarity, I would recommend first to read more about power-supply design and basic components. Without such basic knowledge you will rather make smoke and cause damage.
Power supplies look easy but a good one needs some knowledge.

Good luck!

:?:

i think u quoted the wrong man.. anyhow ur advice to OP is one which i would also give.. these charger thingies are higly one job specific .. to modify them so siginificantly means ... ... a lot of work... risk .. and worst no result....

 

[mister_rf]

He can try, that’ s not so difficult to replace some components… That’s part of the learning process.

 

[godfreyl]

Half the magic smoke escaped already. No sense stopping now.

 

[mister_rf]

I have tested for the original AC-15E Nokia charger. See the results here:
:-D

 

[jiripolivka]

@mister_rf is having Original charger ...

and @hussien55 is havng "fake" charger . it is not original nokia charger let alone the mentioned one/... first get original charger bro ..

From all I could see, also from Youtube, I would say this:

In principle any AC/DC converter can be open and modified, to generate any voltage from e.g. 5V to say 12 VDC. The action shown is extremely dangerous and irresponsible.

The Nokia and other chargers have NOT been designed for such modifications. You can kill yourself as well as any device connected to the "modified" charger.

Nokia and other charger designers and makers carefully adjusted the charger to work with a particular expensive battery in a cell phone. Such batteries need the charging voltage and current within specified limits, to achieve a long life. Any unauthorized modification will cause a damage to the battery and/or other device you choose to connect.

If you need a good AC/DC regulated power supply, buy or build one to your specifications. Attempting to modify "a Nokia" or other chargers is possible but irresponsible play with your life (and others), and potentially damaging to connected devices.

 

[khankll]

From all I could see, also from Youtube, I would say this:

In principle any AC/DC converter can be open and modified, to generate any voltage from e.g. 5V to say 12 VDC. The action shown is extremely dangerous and irresponsible.

The Nokia and other chargers have NOT been designed for such modifications. You can kill yourself as well as any device connected to the "modified" charger.

Nokia and other charger designers and makers carefully adjusted the charger to work with a particular expensive battery in a cell phone. Such batteries need the charging voltage and current within specified limits, to achieve a long life. Any unauthorized modification will cause a damage to the battery and/or other device you choose to connect.

If you need a good AC/DC regulated power supply, buy or build one to your specifications. Attempting to modify "a Nokia" or other chargers is possible but irresponsible play with your life (and others), and potentially damaging to connected devices.

yes no doubt about these statements..
but afterall it was experiment which mister_rf did excellantly... now it shouldbe used with extreme care ...

 

[mister_rf]

:arrow: In my opinion the chance of being injured by an electric shock increase when we start build our power supply, if we are not competent to do so. That’s usually a more complex electrical task and should only be carried out by someone who has been trained to do that. Those who wish to undertake electrical testing work would normally be expected to have more knowledge and be able to demonstrate competence through the successful completion of a suitable training course.

For this experiment all the work was done in the primary section. No modifications of the transformer circuit, no other changes were made in order to compromise the AC lines/DC low voltage isolation, basically that’s low risks operation compare to the risks we normally assume building from scratch any SMPS…

By the other hand, it is very clear such a modified charger not to be used for charging a mobile phone anymore, that’s the idea of the experiment. :roll: