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Jinkela

Wed Jul 18 2012, 02:38AM

Registered Member #5788 Joined: Tue Jul 17 2012, 11:25PM
Location:
Posts: 9

Sulaiman wrote ...

Since neither you nor I know the halogen transformer frequency
or the inductance of your primary on the flyback transformer
I can't give a definite answer,

If 0.68 uF is what you have, use it,
before you make a 'good' primary
try 8,7,6,5,4... turns with the 0.68 uF capacitor, see if there is a 'sweet spot'
the capacitor should be in parallel with (across)
the flyback primary and halogen transformer output

If the halogen transformer can survive, a series-resonant arrangement
would probably get the most power output
with the capacitor in series with the flyback primary,
if the resonant frequency matches the halogen transformer output frequency
you will get the most power throughput
you may also destroy your flyback secondary due to over-voltage. ;)

A halogen transformer can be used to drive a flvback transformer.The method is quite simple!
Firstly replace the transistor with powerful MOSFET like IRFP460
Secondly replace the transformer with your flvback transformer, U can use the primary winds inside the flvback transformer
Third put a 100w 220V light bulb in series with the modified circuit(to prevent the MOS explode) and connect it to 220v to see whether it can work or not
If the light bulb is very bright, that means your circuit not working properly, maybe you need to change the ratio of the feedback tansformer in the halogen transformer PCB to make the circuit vibrate.
If the light bulb is not on or looks very dark, that means you already success 70%, now you can try to make arc from the flvback transformer, the light blub will be brighter when you making arc, dont worry
Finally the most dangerous part,connect the modified circuit to 220V directly!!!Usually it will be alright, but sometimes when you making arcs,the MOS will explode because it's too powerful!!!!!!!!

zippotix

Thu Aug 09 2012, 06:37PM

Registered Member #5208 Joined: Thu Jun 07 2012, 06:12PM
Location:
Posts: 86

I was wondering if anyone was or is using "industrial power supply" to power ZVS? I mean something like this

I'm thinking about buying one, as charging car batteries is kinda annoying, and takes quite much space. Do you think output of this thing needs rectification?
EDIT: Jinkela, thanks for input, but I think it's not worth the effort ;). I'm afraid I would destroy something in the process.

Harry

Thu Aug 09 2012, 07:19PM

Registered Member #4081 Joined: Wed Aug 31 2011, 06:40PM
Location: UK
Posts: 139

Nope it is already rectified, you can see the -V and +V outputs, implying it is DC. I don't know of anyone who uses one but plenty of people use PC power supplies. I reckon it would work as long as you don't exceed the rated current output

zippotix

Sat Aug 11 2012, 11:47AM

Registered Member #5208 Joined: Thu Jun 07 2012, 06:12PM
Location:
Posts: 86

The site says it has in built overload protection, overvoltage protection etc. BTW, I tried to kill a electrolytic cap (330uF 200WV)with a flyback and failed. I forgot about it and left it on the bench, and next day I grabbed it and it shocked me. Not very smart of me, I know. Anyway, I used some online calculator, and according to this, the cap was charged to 66000 Joules, and 6.6 Coulombs. Is that even possible? Isn't that much energy instantly lethal?

Dr. ISOTOP

Sat Aug 11 2012, 12:03PM

Registered Member #2919 Joined: Fri Jun 11 2010, 06:30PM
Location: Cambridge, MA
Posts: 652

zippotix wrote ...

The site says it has in built overload protection, overvoltage protection etc. BTW, I tried to kill a electrolytic cap (330uF 200WV)with a flyback and failed. I forgot about it and left it on the bench, and next day I grabbed it and it shocked me. Not very smart of me, I know. Anyway, I used some online calculator, and according to this, the cap was charged to 66000 Joules, and 6.6 Coulombs. Is that even possible? Isn't that much energy instantly lethal?

The cap charging load probably caused the flyback output to sag below 200V; a 200WV electrolytic will die and vent not far above that.

zippotix

Sat Aug 11 2012, 12:09PM

Registered Member #5208 Joined: Thu Jun 07 2012, 06:12PM
Location:
Posts: 86

Oh, so it won't charge above 200V? It gave me a good jolt, when shorted on metal plate it gives a loud bang and left 2 small holes. Is it relatively safe?

brandon3055

Sat Aug 11 2012, 03:58PM

Registered Member #4548 Joined: Mon Apr 23 2012, 03:52AM
Location: tasmania
Posts: 271

I think it is highly unlikely to get a lethal jolt from a capacitor if the charge is only traveling through your hand also if you can measur the resistants of your hand you should be able to use ohms law to find out exactly how much current you were exposed to (about 30ma is lethal) but again that might only be if it is traveling through your body but I don't recommend testing this theory haha

zippotix

Tue Aug 14 2012, 11:36AM

Registered Member #5208 Joined: Thu Jun 07 2012, 06:12PM
Location:
Posts: 86

Thanks Destroyer. Guys, I'm making a high current mot transformer, and while cutting off the secondary, I accidently nicked primary, like this

Is there anything I can do?

brandon3055

Wed Aug 15 2012, 01:46PM

Registered Member #4548 Joined: Mon Apr 23 2012, 03:52AM
Location: tasmania
Posts: 271

I have done that a cople of times I found a good way to fix it is just to make shore the windings aren't shorted then put some super glue on the damaged part followed by a few layers of tissue paper and that seems to work ok for me but you should waight to se what others have to say first

zippotix

Thu Aug 16 2012, 11:58AM

Registered Member #5208 Joined: Thu Jun 07 2012, 06:12PM
Location:
Posts: 86

Yup, will try it and report how it works. If not, I can get another mot, plenty of microwaves near dump site. I don't know much about mots, but if I understand well, the current draw must be limited to not break the fuse (mine is 16A)? Is running a mot in resonance with 2 or 4 hv caps reducing the current draw?

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