Microwave inverter into power supply

Thread Starter

Gabriell

Joined Jan 16, 2016
47
I pulled out a microwave oven inverter today and i was wondering if i could make it into a power supply just like the older microwave oven transformers.

Can i rewire the secondary just like the big old ones? any tips how could i turn it into a 120v power supply?

Thanks
 

Thread Starter

Gabriell

Joined Jan 16, 2016
47
IMG_2299.JPG IMG_2300.JPG IMG_2301.JPG
Maybe this image will help. Not many reply's so far...
I tried to connect it 240v but it just blow my fuse.
Internet search doesn't give much on these things. Anyone familiar with these things??????
 

Hypatia's Protege

Joined Mar 1, 2015
3,223
I pulled out a microwave oven inverter today and i was wondering if i could make it into a power supply just like the older microwave oven transformers.

Can i rewire the secondary just like the big old ones? any tips how could i turn it into a 120v power supply?

Thanks
A 12V DC to 120V 60 Hz inverter is best realized via 'double conversion' topology -- Although a MOT inverter transformer may be used in the first stage of such a scheme, IMO such is not practical in consideration of the amount of rewinding required -- That said, MOT inverters are excellently applied to LVDC → HVDC conversion where space/weight economy are desirable (e.g. the plate [i.e. anode] supply in tube operated mobile communication equipment) :):):)

Best regards and have fun!:)
HP
 

Hypatia's Protege

Joined Mar 1, 2015
3,223
@Gabriell
...On the other hand, If you merely want a DC PSU you may 'unwind' the secondary to such extent that the EMF is 'in range of' your proposed rectification/regulation scheme... Note that the operation/output frequency (tens of kHz) is significantly easier to filter than 60hZ!:cool:

Best regards
HP
 

Thread Starter

Gabriell

Joined Jan 16, 2016
47
Thank you for your message!
I wish i would understand what you are trying to say but im lost. :(
The inverter runs on DC instead of AC?
 

Thread Starter

Gabriell

Joined Jan 16, 2016
47
@Gabriell
...On the other hand, If you merely want a DC PSU you may 'unwind' the secondary such extent that the EMF is 'in range of' your proposed rectification/regulation scheme... Note that the operation/output frequency (tens of kHz) is significantly easier to filter than 60hZ!:cool:

Best regards
HP
So if i rewind the secondary and apply dc voltage to the primary it should be ok?
 

Hypatia's Protege

Joined Mar 1, 2015
3,223
Thank you for your message!
I wish i would understand what you are trying to say but im lost. :(
The inverter runs on DC instead of AC?
The inverter proper operates on DC derived from rectification of mains current -- howbeit, the unit as a whole is essentially a 60HZ mains 'voltage' to high 'voltage' DC converter.....
 
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Hypatia's Protege

Joined Mar 1, 2015
3,223
So... If you want a lower 'voltage' DC power supply -- You need only modify the secondary (and, perhaps, the secondary circuit) for the desired output -- then power the unit from the mains (as it was connected in the microwave oven)...:)

Best regards
HP
 

Thread Starter

Gabriell

Joined Jan 16, 2016
47
Unfortunately i dont have circuit anymore. I will try to salvage another one.

So i cant just unwind the secondary and apply AC and then connect it to a bridge rectifier?
 
Unfortunately i dont have circuit anymore. I will try to salvage another one.

So i cant just unwind the secondary and apply AC and then connect it to a bridge rectifier?
Unfortunately the magnetic properties of ferrite preclude said application at low frequencies (CIP 60Hz) -- that said, you may be able to build a simple driver (of, for instance, resonant Royer/"ZVS" topology)... Can you run a continuity test on the transformer and post the results?

Best regards
HP
 
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Thread Starter

Gabriell

Joined Jan 16, 2016
47
Hmmm probably is should have told you first that im not an electrician and my knowledge is very limited. I have no idea how to do a continuity test and i dont know what " resonant Royer/"ZVS" topology" means...
But i appreciate your help!!!
 
Hmmm probably is should have told you first that im not an electrician and my knowledge is very limited. I have no idea how to do a continuity test and i dont know what " resonant Royer/"ZVS" topology" means...
But i appreciate your help!!!
Ok I hear you! - No problem:) -- I think your best move is to salvage another inverter -- Don't remove the transformer unless necessary to access the secondary --- when ready please let me know, and I'll be happy to 'walk you through' the modification!:cool:

Best regards
HP:)

PS -- Many microwave ovens equipped with conventional MOTs are still 'floating around' --- Should you go that route, please try to find an older unit inasmuch newer MOTs tend to have small cores and, hence, rather low saturation thresholds...
Also - Please hold on to your present inverter transformer! -- Someday you'll be glad you did!:):):)


Very best regards
HP
 
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