Help with milwaukee m12 m18 charger conversion

[Nitzanman]

I have an m12 m18 charger which i tried to convert from 120 to 220v.

I did everything i was supposed to but forgot one main part, to scrape one of the circuit lines.

After replacing the varistor and diode as shown in the tutorial video on youtube. I connected the charge, heard some kind if electrical noise and then nothing.

I later found out i was supposed to scrape out one of the lines on the circuit for it to work.

Now my main question is what may have i burned and how should i go about checking that.

Nothing happens when i connect the charger to the outlet.

This is the link to the video:

https://youtu.be/4cnPb2P4I9k

 

[Geoff1946]

The power semiconductors are the most likely victims. It looks like an invertor circuit so check the rectifier at the input; if you were REALLY lucky it may have acted as a fuse. Next suspect would be the invertor transistor or thyristor . Look for visible damage. these often swell or split the case if overstressed.  

It's hard to say anything further without a schematic, even whether the change you attempted was viable. If it was designed for adaptation to alternative supplies there would be simple links to change on the board. 

In the worst case you could have caused multiple faults and perhaps destroyed every semiconductor..

Your best bet is probably find one on e-bay.

 

[Nitzanman]

The power semiconductors are the most likely victims. It looks like an invertor circuit so check the rectifier at the input; if you were REALLY lucky it may have acted as a fuse. Next suspect would be the invertor transistor or thyristor . Look for visible damage. these often swell or split the case if overstressed.  

It's hard to say anything further without a schematic, even whether the change you attempted was viable. If it was designed for adaptation to alternative supplies there would be simple links to change on the board. 

In the worst case you could have caused multiple faults and perhaps destroyed every semiconductor..

Your best bet is probably find one on e-bay.

Thanks for the reply, i will check and update.

Whats the best way to upload photos to here?

Thanks

 

[Sharpend]

Would it not be easier to just by the correct charger? 
https://www.sgs-engineering.com/m12-18fc-rapid-fast-charger?

 

[Nitzanman]

Would it not be easier to just by the correct charger? 
https://www.sgs-engineering.com/m12-18fc-rapid-fast-charger?

It would, but then i would feel useless

 

[Sharpend]

It would, but then i would feel useless

oh go on then repair it

 

[myke]

I have an m12 m18 charger which i tried to convert from 120 to 220v.

I did everything i was supposed to but forgot one main part, to scrape one of the circuit lines.

After replacing the varistor and diode as shown in the tutorial video on youtube. I connected the charge, heard some kind if electrical noise and then nothing.

I later found out i was supposed to scrape out one of the lines on the circuit for it to work.

Now my main question is what may have i burned and how should i go about checking that.

Nothing happens when i connect the charger to the outlet.

This is the link to the video:

https://youtu.be/4cnPb2P4I9k

The varistor you changed just limits the mains input spikes which are higher for uk 230v.

You forgot to cut the link on the voltage multiplier so the voltage was multiplied x 2 . The charger used a voltage multiplier to increase the 120v rms to 240v rms.

Cutting the link makes it a simple bridge rectifier feeding 240v into the switch mode PSU. Conversely 120v with the link in gives 240v

Because you have not cut the link the voltage going into the switch mode PSU was doubled if you are lucky a cap will have burst look for a swollen end on the large capacitors (where the cross is on the top) 

What diode did you change ?? is it in the correct way? 

 

[kerching]

It would, but then i would feel useless

You may have proved your uselessness by NOT scraping the track! :slap :facepalm:

i once put 500V through some electronics on a very expensive control panel, whoops!

 

[Nitzanman]

Ok i would like to update.

After acquiring a multimeter from a friend. I checked all components that have any thing to do with the voltage drop (capacitors, diodes, rectifier,  coils, varistor and so forth) and found that all have the expected outcome on the multimeter. I then noticed a round slow burn fuse that comes right after the mains voltage. Checked it and saw that it has 0 continuity. 

I soldered a temporary bridge that overlaps the fuse and the charger now works. 

Thanks for everyone that tried helping. 

 

[Geoff1946]

Ok i would like to update.

After acquiring a multimeter from a friend. I checked all components that have any thing to do with the voltage drop (capacitors, diodes, rectifier,  coils, varistor and so forth) and found that all have the expected outcome on the multimeter. I then noticed a round slow burn fuse that comes right after the mains voltage. Checked it and saw that it has 0 continuity. 

I soldered a temporary bridge that overlaps the fuse and the charger now works. 

Thanks for everyone that tried helping. 

View attachment 11004

Go and get yourself a Lottery ticket!

 

[Nitzanman]

Go and get yourself a Lottery ticket!

I guess my only luck in life is burning just the fuse and not the whole device.