Nokia ACH-6E, AC-4E

[neuron]

Hi,

I have several Nokia charger - ACH-6E, AC-4E ...

All of them have a 10 Ohm resistor in the 220 V.

220V -> 10 Ohm -> 4 diodes -> 2x 6,8 uF 400 V ...

and in AC-4E the resistor is burn.

Tested the Caps with EVB - ESR ok

SMD with Smart Tweezers ok ... several caps and resis.

Why 10 Ohm blow ?



Best Regards,
Ruy

[ben7]

Re: Nokia ACH-6E, AC-4E

Shorted out diodes, or power transistor.

The 10 ohm resistor is used as a half-assed replacement for a regular fuse, because it is cheaper

Can you get some good pictures?

[cheapie]

Re: Nokia ACH-6E, AC-4E

Shorted out diodes, or power transistor.

The 10 ohm resistor is used as a half-assed replacement for a regular fuse, because it is cheaper

Can you get some good pictures?

I had a charger once where I had replaced the primary cap. I didn't notice it at the time, but I had a solder bridge across it. I plugged it in and the resistor burnt up. Thinking it wasn't important, I jumpered it and plugged the charger in again. The bridge rectifier promptly exploded and tripped the breaker as well.

[neuron]

Re: Nokia ACH-6E, AC-4E

Shorted out diodes, or power transistor.

The 10 ohm resistor is used as a half-assed replacement for a regular fuse, because it is cheaper

Can you get some good pictures?

Thank you ben7 and cheapie,

I have LCR and ohmmeter - "Smart Tweezers".

I will check and report - the 4 diodes or the T.

The L10 is very low and the reading is very nH ... its strange

Best regards,
Ruy

[neuron]

Re: Nokia ACH-6E, AC-4E

Thank you ben7 and cheapie,

I have LCR and ohmmeter - "Smart Tweezers".

I will check and report - the 4 diodes or the T.

The L10 is very low and the reading is very nH ... its strange

The quality is bad ... Hope you can id.

Best regards,
Ruy

[neuron]

Re: Nokia ACH-6E, AC-4E

Thank you ben7 and cheapie,

I have LCR and ohmmeter - "Smart Tweezers".

I will check and report - the 4 diodes or the T.

The L10 is very low and the reading is very nH ... its strange

Hi,

Transistor (in circuit)
Z= 114 Ohm, 4.941 Ohm, 116 Ohm

4 Diodes
Z= 928.9 Ohm, 926 Ohm



Different model and (its working) the Transitor Z=172 KOhm between legs.
If I put in AUTO MODE the "Smart Tweezers"
Transistor - in good unit - 929 pF or 12 uF
In bad unit always Z=116 Ohm and 4,941 Ohm

Regards,
Ruy

[mariushm]

Re: Nokia ACH-6E, AC-4E

Pictures are useless. Move the camera further away and try to snap pictures again. Get the pictures in focus, it's not rocket science.

[neuron]

Re: Nokia ACH-6E, AC-4E

Hi,

Transistor (in circuit)
Z= 114 Ohm, 4.941 Ohm, 116 Ohm

The two big caps in left 6,8 uF 400 V.

4 diodes 1N4007

The green Resistor 10 Ohm - burn.

The Inductance L10 between the 2 big caps and the 4 diodes
I can't measure the Henry ..... very low mOhm

And 2 SMD - R21, R14 usually are black with the Ohm numbers, this ones are green ...

Regards,
Ruy

[neuron]

Re: Nokia ACH-6E, AC-4E

The two big caps in left 6,8 uF 400 V.

Any member see leaky capacitor in this 6,8 uF or in final stage ?

In the 220V the caps get short?
But with LCR everything ok. 0,2 - 0,5 - 1 V

Regards,
Ruy

[imp]

Re: Nokia ACH-6E, AC-4E

Again, please provide us with focused pictures. These are useless for us

[eccerr0r]

Re: Nokia ACH-6E, AC-4E

I don't know if this is any use but here's my Nokia AC-10C guts:
Fairly common 2-transistor optoisolated feedback design with fullwave rectifier. This one works actually, but the problem I had with it turned out to be mechanical...

[neuron]

Re: Nokia ACH-6E, AC-4E

Again, please provide us with focused pictures. These are useless for us

Thank for your comments,

But at moment I don't have a camera with better resol.

I described the components in detail, If you have any doubt about any piece please tell me.

Any comment:
"Any member see leaky capacitor in this 6,8 uF or in final stage ?"

Sometimes they leak - shortcircuit in 220V, ... antique radios

Regards
Ruy

[imp]

Re: Nokia ACH-6E, AC-4E

I can´t see any faults in the pictures you provided - they are to blurry.

You must understand that it´s impossible for us to help you (or any other member) without proper information and, in most cases, clear pictures. Otherwise it´s like telling a blind person how the color red looks like ....

[neuron]

Re: Nokia ACH-6E, AC-4E

Shorted out diodes, or power transistor.

And the values for the short - Ohm? .... I write the values i have in circuit ... strange or normal????



Sometimes they leak - shortcircuit in 220V, ... antique radios
Any member have experience one this with modern circuits?

Regards
Ruy

[neuron]

Re: Nokia ACH-6E, AC-4E

Thank you for your comments,



Update

I removed the coil (between 2x 6,8 uF 400 V).
And the short-circuit disappear (test with a series light bulb).
The diodes and the first 6,8 uF-400 V ok - the first cap has hundred volts

Insert again the coil and removed the second 6,8 uF 400 V ... short on.

The 2 caps and the diodes are ok.



The board has TH 2267.1 0706.

I searched and this is a special IC.


Regards,
Ruy

[ben7]

Re: Nokia ACH-6E, AC-4E

Thank you for your comments,



Update

I removed the coil (between 2x 6,8 uF 400 V).
And the short-circuit disappear (test with a series light bulb).
The diodes and the first 6,8 uF-400 V ok - the first cap has hundred volts

Insert again the coil and removed the second 6,8 uF 400 V ... short on.

The 2 caps and the diodes are ok.



The board has TH 2267.1 0706.

I searched and this is a special IC.


Regards,
Ruy

Replace the main switching transistor

[neuron]

Re: Nokia ACH-6E, AC-4E

Replace the main switching transistor

Thank you for your comments,

Removed the transistor and
/---------\
|_1_2_3_|

Pins 1 - 2 -> 4,6 Ohm in all directions.

The T. has a short.

"Petit Problem" the bottom is all burn and I can't get the name and the number.

Measured the main path in caps, in main transf. and now
we don't get low Ohm.

Connected 220V and "no short".

The only problem, I can't read or get the type of Transistor.

Best Regards,
Ruy

[ben7]

Re: Nokia ACH-6E, AC-4E

Thank you for your comments,

Removed the transistor and
/---------\
|_1_2_3_|

Pins 1 - 2 -> 4,6 Ohm in all directions.

The T. has a short.

"Petit Problem" the bottom is all burn and I can't get the name and the number.

Measured the main path in caps, in main transf. and now
we don't get low Ohm.

Connected 220V and "no short".

The only problem, I can't read or get the type of Transistor.

Best Regards,
Ruy

Which pin on the transistor connects to the "-" of the 400V filter capacitors, and which pin on the transistor connects to a pin on the transformer?

[neuron]

Re: Nokia ACH-6E, AC-4E

Which pin on the transistor connects to the "-" of the 400V filter capacitors, and which pin on the transistor connects to a pin on the transformer?

Thank you for your comments,

Pin 1 -> TH 2267.1 0706 right pin (bottom),
Pin 2 -> The transformer,
Pin 1 -> "-" Caps but there is a serie of SMD

Regards,
Ruy

[neuron]

Re: Nokia ACH-6E, AC-4E

Thank you for your comments,

Pin 1 -> TH 2267.1 0706 right pin (bottom),
Pin 2 -> The transformer,
Pin 1 -> "-" Caps but there is a serie of SMD

As I mentioned before I can send details of components.



Regards,
Ruy