Home
JAQForum Ver 20.06
Log In or Join  
Active Topics
Local Time 22:53 07 Jul 2020 Privacy Policy
Jump to

Notice. New forum software under development. It's going to miss a few functions and look a bit ugly for a while, but I'm working on it full time now as the old forum was too unstable. Couple days, all good. If you notice any issues, please contact me.

Forum Index : Electronics : Basic torroid bulk charger from gen 240v

     Page 2 of 2    
Author Message
noneyabussiness
Senior Member

Joined: 31/07/2017
Location: Australia
Posts: 265
Posted: 01:44pm 24 Apr 2020
Copy link to clipboard 
Print this post

Ok... sorry for late reply... yes out of the box  it was at " full " current 1200watts.. once i put the extra 3 turns ( trial and error , started with 2 etc) it will happily max out now at about 3.5kw , i usually only have it under 2kw as i don't usually need more than that...

The 3 ive modded for this use have all been full bridge, igbt transformer driver , current controlled ( no voltage control that i can see) , funnily enough only half wave rectified on the secondary,  with 3-4 high powered diodes in series on same heatsink.

What i can see in the pics you have provided look very similar,  the big green toroid is the transformer that needs the extra turns, you will have to work out the secondary, follow it to output diodes..each turn makes a significant difference so i would start with 2 and go from there..

Once sorted they are very tough...
I think it works !!
 
noneyabussiness
Senior Member

Joined: 31/07/2017
Location: Australia
Posts: 265
Posted: 01:49pm 24 Apr 2020
Copy link to clipboard 
Print this post

Oh and the rating, take it with a grain of salt.. 200amp for short bursts, but it gets warm putting 3kw in for hours on end, so doubt it could 9.6kw for extended periods of time.. but for a 100 bucks it is a tough charger once setup..

Honestly i would like to up the input cable even for 3kw, gets warm.. damnt, hasn't missed a beat but you mob got me worried now..
I think it works !!
 
renewableMark

Guru

Joined: 09/12/2017
Location: Australia
Posts: 1564
Posted: 10:50pm 24 Apr 2020
Copy link to clipboard 
Print this post

Thanks Noneya.

Mike there was another two connections, total of 6 ends, so 3 coils.

OK so the common connection on the right is the one that goes to the negative output on the welder.

That common connection has continuity to each of the other two ends.



Those two ends go to the left and have a diode on each side of a heatsink.




Cheers Caveman Mark
Off grid eastern Melb
 
wiseguy

Guru

Joined: 21/06/2018
Location: Australia
Posts: 470
Posted: 10:55pm 24 Apr 2020
Copy link to clipboard 
Print this post

Ok, pull out the two ends going to the diodes and add 2 more turns to them and terminate the new ends in the same holes - wont matter if they cross over (swap sides) in the process it is a full wave rectifier.

Show Tony how its done ¬†   PS if it goes bang my previous posts will self destruct.....
Edited 2020-04-25 08:56 by wiseguy
If at first you dont succeed, I suggest you avoid sky diving....
Cheers Mike
 
noneyabussiness
Senior Member

Joined: 31/07/2017
Location: Australia
Posts: 265
Posted: 11:03pm 24 Apr 2020
Copy link to clipboard 
Print this post

Check open circuit voltage, all ones ive done are around the 90v mark, to get the most out of them... they are current controlled so don't worry about the high OC voltage...
I think it works !!
 
noneyabussiness
Senior Member

Joined: 31/07/2017
Location: Australia
Posts: 265
Posted: 11:04pm 24 Apr 2020
Copy link to clipboard 
Print this post

If i get a chance today, ill get some photos of mine if it will help...
I think it works !!
 
Warpspeed
Guru

Joined: 09/08/2007
Location: Australia
Posts: 3263
Posted: 11:26pm 24 Apr 2020
Copy link to clipboard 
Print this post

All sounds quite reasonable.

I think I will just watch the fun from a safe distance.
Cheers, Tony.
 
renewableMark

Guru

Joined: 09/12/2017
Location: Australia
Posts: 1564
Posted: 11:29pm 24 Apr 2020
Copy link to clipboard 
Print this post

Thanks guys,
I'm only getting 62v OC.

Out of the box it only provides 1.9A so it appears to be made with a much lower voltage to your I-max one.

I need a little welder anyway, so it may be wise to just put this back together and buy the same I-max one and copy your proven mods.
Cheers Caveman Mark
Off grid eastern Melb
 
renewableMark

Guru

Joined: 09/12/2017
Location: Australia
Posts: 1564
Posted: 11:46pm 24 Apr 2020
Copy link to clipboard 
Print this post

Did a bit of tracing back to see where things go.


















Where I'm holding the probes there is continuity.

So it looks like the 5010 rectifies the 240v and the IGBT's control the feed to the HV winding (where the two connections are in the centre)
Then the two windings connected to Neg and diodes pick up the lower voltage.
Edited 2020-04-25 09:48 by renewableMark
Cheers Caveman Mark
Off grid eastern Melb
 
wiseguy

Guru

Joined: 21/06/2018
Location: Australia
Posts: 470
Posted: 12:39am 25 Apr 2020
Copy link to clipboard 
Print this post

Well done Mark good detective work.  It appears to have 2 x IGBTs making it a half bridge drive to the output toroid.  The Other side of the power winding appears to go through a one turn current sense transformer (the little thing marked by small single arrow "here" in your third picture) and then through a big film capacitor (reddish thing) back to probably the negative side of the 470u capacitor.

Open circuit voltage can be misleading I see yours uses a snubber across the diode - this may be the reason for your lower voltage.  The 75 - 90V measured by others may not be a "real" voltage and have little current available behind it.

Personally I see miniscule risk in adding 2 turns to your transformer secondaries but if you are more comfortable and want to follow a proven recipe - also a good plan.
If at first you dont succeed, I suggest you avoid sky diving....
Cheers Mike
 
renewableMark

Guru

Joined: 09/12/2017
Location: Australia
Posts: 1564
Posted: 05:19am 25 Apr 2020
Copy link to clipboard 
Print this post

Frigg, just did a big long post and hit save post and lost it, system had logged me out.

Decided to do it.

Anyway I got it to work
99v O/C

I ended up rewinding the torroid, gave it 2 extra turns.

From socket on wall it puts out 42A at half power setting, I didn't want to push it anymore than that.
I'm happy with a 2kw charger.

Tried it on the little gen and it will feed 1700 watts to the battery before it overload cuts out.

The bigger gen runs it fine for 2000watts, so happy with the outcome.

Thanks for all the help guys.



Cheers Caveman Mark
Off grid eastern Melb
 
renewableMark

Guru

Joined: 09/12/2017
Location: Australia
Posts: 1564
Posted: 05:20am 25 Apr 2020
Copy link to clipboard 
Print this post

Wonder if I can still weld with it?
Cheers Caveman Mark
Off grid eastern Melb
 
wiseguy

Guru

Joined: 21/06/2018
Location: Australia
Posts: 470
Posted: 05:28am 25 Apr 2020
Copy link to clipboard 
Print this post

Amazing, I didnt think it would work

Well done Mark !! Maybe smallest rod size might work welding - but I suggest you leave it as a charger now.  Wonder what one turn would have done....
Edited 2020-04-25 15:40 by wiseguy
If at first you dont succeed, I suggest you avoid sky diving....
Cheers Mike
 
renewableMark

Guru

Joined: 09/12/2017
Location: Australia
Posts: 1564
Posted: 05:41am 25 Apr 2020
Copy link to clipboard 
Print this post



For those who haven't seen one, these are tiny and weigh stuff all.

You would never know it has been modded by looking at it.
If it goes bang at some point the transformer can be un soldered by the 6 pins and swapped into a new one.
It was actually quite easy to de solder, just place a flat blade screwdriver under the sub pcb and heat the pins and it flexes a bit and lifts away when the solder is warm enough.
Cheers Caveman Mark
Off grid eastern Melb
 
renewableMark

Guru

Joined: 09/12/2017
Location: Australia
Posts: 1564
Posted: 05:42am 25 Apr 2020
Copy link to clipboard 
Print this post

Thanks Noneya for the idea mate.
Cheers Caveman Mark
Off grid eastern Melb
 
noneyabussiness
Senior Member

Joined: 31/07/2017
Location: Australia
Posts: 265
Posted: 10:18pm 25 Apr 2020
Copy link to clipboard 
Print this post

No worries,  glad to be of help.. it was actually OZ's idea originally by memory ( well at least where i got it from ).. they are tough, mines be going as a charger for about 2 years now...
I think it works !!
 
renewableMark

Guru

Joined: 09/12/2017
Location: Australia
Posts: 1564
Posted: 06:46am 26 Apr 2020
Copy link to clipboard 
Print this post

Hey, what's the O/C volt of your modded one?
Cheers Caveman Mark
Off grid eastern Melb
 
noneyabussiness
Senior Member

Joined: 31/07/2017
Location: Australia
Posts: 265
Posted: 09:04am 26 Apr 2020
Copy link to clipboard 
Print this post

96v.. but as was mentioned earlier,  there is no " power " at that voltage.. its because its current controlled not voltage controlled..
I think it works !!
 
noneyabussiness
Senior Member

Joined: 31/07/2017
Location: Australia
Posts: 265
Posted: 09:05am 26 Apr 2020
Copy link to clipboard 
Print this post

To be on safe side,  i always hook to battery first... then power it up...
I think it works !!
 
     Page 2 of 2    
Print this page


To reply to this topic, you need to log in.

© JAQ Software 2020