Hello Community,

I'm attempting to repair the SMPS on a Levoit 600S air purifier. The transformer is likely open. It has six pins. 2 pairs on the primary side (one pair tested open) and 1pair of legs on the secondary side. Legs on the secondary side are spread wide apart (end-to-end). I've circled them in blue. Dimentons of the transformer are 22x23mm. Marking on the transformer are EE16 1.9mH-B. Fuse for the powerboard is fuse 250V 3.15A. I've been unable to find an exact match and I'm hoping for some help here to find a suitable replacment.

Peace
LM

 

Hello Community,

I'm attempting to repair the SMPS on a Levoit 600S air purifier. The transformer is likely open. It has six pins. 2 pairs on the primary side (one pair tested open) and 1pair of legs on the secondary side. Legs on the secondary side are spread wide apart (end-to-end). I've circled them in blue. Dimentons of the transformer are 22x23mm. Marking on the transformer are EE16 1.9mH-B. Fuse for the powerboard is fuse 250V 3.15A. I've been unable to find an exact match and I'm hoping for some help here to find a suitable replacment.

Peace
LM

https://www.google.com/search?sa=N&...1380&dpr=0.9#vhid=GDq-4xUmelHIrM&vssid=mosaic

 

Hello Community,

I'm attempting to repair the SMPS on a Levoit 600S air purifier. The transformer is likely open. It has six pins. 2 pairs on the primary side (one pair tested open) and 1pair of legs on the secondary side. Legs on the secondary side are spread wide apart (end-to-end). I've circled them in blue. Dimentons of the transformer are 22x23mm. Marking on the transformer are EE16 1.9mH-B. Fuse for the powerboard is fuse 250V 3.15A. I've been unable to find an exact match and I'm hoping for some help here to find a suitable replacment.

Peace
LM

https://www.google.com/search?sa=N&...1380&dpr=0.9#vhid=GDq-4xUmelHIrM&vssid=mosaic

Thanks my friend I did give it a go, but stuggled to find a 6-pin or one that was suitable for my power ratings or readily available on ebay, ali, etc..

 

The transformer is likely open

Transformers do not fail often. I think you will not find a replacement.
What is the part number for IC2?
I see two secondaries.
Are you certain there are more than one winding on the primary.

 

Thanks my friend I did give it a go, but stuggled to find a 6-pin or one that was suitable for my power ratings or readily available on ebay, ali, etc..

Yes, I see there's a huge set of options out there, check Amazon I saw a few contenders, Chinese of course but likely a workable option.

 

Have you done a resistance check of the transformer to verify that there is an open winding?? Like RS states, transformers seldom fail. I would suspect other parts first, UNLESS the product has been dropped. Transformers can be mechanically damaged by sudden impacts.

 

Hello Friends,

Thank you all for chipping in. I have a working board that I've used to help troubleshoot.
One pair of the legs on the transformer definitely tested open (not the case on the know good board)
I've change all the eletrolytic caps execept for the main big boy, which is puting out 300+ volts.
I've change the ic ( OB2358SP ) and the ceramic cap that attaches to it directly
I've change the Bridge Rectifier
I've changed the fuse
Diode close to the ic tested ok (.6) out of circuit. This connection between this diode and the transformer (pair of open legs) is open--this is not the case on the working board.

Is there a way to safetly rule out or confirm the transformer? Admittedly, I've never had to change one but this case maybe the exception. The problem is I can find one.

 

I have a working board that I've used to help troubleshoot.

Good!

One pair of the legs on the transformer definitely tested open (not the case on the know good board)

Good
Can you see the wires going to the open pins. Maybe the solder job on the pins are bad. (solder wire to pin AND pins to PCB)

 

Checked those but double checking now...

 

Good!

Good
Can you see the wires going to the open pins. Maybe the solder job on the pins are bad. (solder wire to pin AND pins to PCB)

Solid continuity on the lines for both pins, of the pair that matches the know good. But no continuity between the pair of legs themselves

 

Have you done a resistance check of the transformer to verify that there is an open winding?? Like RS states, transformers seldom fail. I would suspect other parts first, UNLESS the product has been dropped. Transformers can be mechanically damaged by sudden impacts.

408k ohms between the bad pair and 1ohm between the good pair (all on the bad board). 1ohm between both pairs on good board.

 

408k ohms between the bad pair and 1ohm between the good pair (all on the bad board). 1ohm between both pairs on good board.

OK I believe you have a bad transformer.
Transformers for switching power supplies are not commonly available. A 220V to 12V 60hz transformer you can get anywhere. This one we don't think you can find.

 

The problem is, of course, that it is a CUSTOM transformer with a high voltage secondary. SO YES, IT CAN ACTUALLY BE OPEN. It might be a wire break at a terminal connection, THAT might be repairable. Maybe. IF you can find the same assembly at a dealer, that could be one option. It is not at all likely that there is a replacement for such a specialized part.

 

:/ Thank you all for your input. I'll have to set a notification on eBay--spare boards also seem an unlikely find.
I appreciate you all sharing the knowledge

 

Have you investigated the price of a replacement PCB assembly??