Siemens Sitop Power 20 1PH 6EP1336-2BA00 repair ?

[Noy]

Bought this "Siemens Sitop Power 20 1PH 6EP1336-2BA00" device from ebay (55€ including shipping, first i thought "good price", afterwards it know it was to expensive.. ) (fleamarkt privat->privat, so no return available.. ) for my "to build" 3D printer..

Just did a fast test, connected it to 230V and 24V was present at the output (no load connected) but it was a bit "clunky" for a siemens build quality so i checked it a bit deeper..

1. All srews were missing.. -> No PE connection to the case..
2. Removed the cover to look in -> 2 Parts were removed (see attached pictures), my guess smoothing caps..
3. rectifier was not connected to the case -> Srew is missing , maybe isolation also?
4. another part on the output was also not connected to the case -> Spring Clamp is missing, isolation present. Where can i find a fitting spring clamp or can i screw it with such a isolation washer to the case?
5. The whole heat dissipation metal thing is missing..:-( -> i think i will buy cheap aluminium sheet and have to bend/drill me a fitting thing..

Hopefully it is working again after that...


Now my whish:
1. Can somebody post pictures from a similar working device? Or do somebody know which caps / parts are missing there?
2. I also need to know thich of the devices needed to be isolatet or not. My guess will be -> rectifier not, other part yes (if i find not a fitting springclip i will screw it with isolation washer.., the 2 "main" switching transistors i don't know.. isolate or not to isolate...?, hopefully it will be clear from other pictures..)

The other things (heatsinks / srews) are a more easy repair (but more work to do than i thought... :-( )

[Per Hansson]

I use what I thought was a very similar power supply when I need more than my lab PSU can provide.
However a Google images search revealed that even though only the end of the part number is changed to 3BA00 they are significantly different!
I know Germany has these special rules for private auctions but can't you at least reach out to the seller?
Maybe he has the parts that are missing or know the guy that do?

Edit: here is some eBay auctions that shows similar PSUs to yours without covers, albeit 3-phase input but only the bridge rectifier stage will be different really:
https://www.ebay.com/itm/Siemens-SITOP-power-10-6EP1434-2BA00-Power-Supply-Untested-AS-IS-/264317668016
https://www.ebay.com/itm/SIEMENS-power-supply-ALIMENTATION-24V-10A-SITOP-POWER-10-6EP1434-2BA00-STAND-3/400691222482
https://www.ebay.com/itm/SIEMENS-SITOP-POWER-10-6EP1434-2BA00/292344329488?epid=169950022

[Noy]

Already talked to him. He bought this for some hobby use but only checked output voltage nothing more.
He doesn't know that this device was "slaughtered".
Now i don't know if i should belive him but the other stuff he sells is all unreleated to electronics stuff, so maybe he is trustworthy and really didn't know.

He said he has no other parts because he didn't know..

So i think it is now my problem ... :-(

All your pictures aren't the right device unfortunally. It looks like the 1ph design are very "rare" in the wild.. Thats why they are even used rather expensive (>100€). 3ph are cheaper..

I found these crusty pictures:
https://articulo.mercadolibre.com.ve/MLV-516905755-fuente-siemens-sitop-24v-20amp-mod-6ep1336-2ba00-_JM

But unfortunally i can't see which caps are missing and also not the connection to the heatspreader. But i can see how "big" this part should be..
Maybe i can build / fit something other into it (have some devent copped heatsinks from a old "design" PC supply pretty heavy.. but tall.. )

[Per Hansson]

I reviewed your photos, the missing parts are not capacitors.
It is before the capacitors and I would hazard a guess that it is protection MOV's.
The device will probably work fine without them if you are unable to find them.
The 3-phase and 1-phase units most likely share the same PCB. (Note how your unit has two missing pins on the input terminal).
It looks like some small SMD components have been burned under the safety Y capacitors.
So it is likely a overvoltage event killed the MOVs that are missing and these SMD components.


For the missing mounting parts refer to my earlier eBay links, they show the clips used to attached to the heat-spreader.

[Noy]

These parts are fine. They are mini melf resistors. 2x  200 in parallel = 100 Ohm (confirmed) the other one is a single 18 Ohm one looks also fine.

Took some better detailed picture now.
They are on the "110V" Jumper -> not set: 2 in series for 230V and if jumper is set 2 in parallel..

They are marked by hand with +/- and both got 2x 220k series resistor in parallel.

Are you sure that these are MOV places? And if yes which spare part could be fit there? Which values are common there?

And why are they series/ paralleld with this 110V jumper? I thought they are cap places because of the jumper / "discharge" resistors..

[Per Hansson]

I think it is wired something like in my attachment.
I am quite sure of the Neutral path, had to guess a bit more for the live L1 path.
The 120v jumper is the same like in a ATX power supply with voltage selector switch.
It brings the AC to the middle of the bulk caps to bring them to 320VDC with only 120VAC input.
If this is correct I guess my first guess about MOVs is wrong.
Could indeed be for capacitors, but I do not see why, the holes in the PCB are polarity marked with the square holes also.
There is also a third leg hole for stability that large capacitors have.

[Noy]

Tried some GIMP magic (something i ever want to do :-))
Tomorrow i will check with continuity test if you are right :-)

[Per Hansson]

I changed the color in my previous picture because it was annoying to have yellow for both live and neutral.
Now green is PE, yellow is L1, neutral is blue, DC- is black and DC+ is red
I may also take back what I wrote in my previous post about it not making sense to be a spot for MOV's:
Because I found some ATX reference schematics and some did infact place the MOV via the middle of the bulk caps.
So maybe in the three phase version this is the place for more caps and in the single phase version it is for MOV's?

Maybe you can also check in my annotated picture lower left corner: the Y-capacitor makes no sense from ground to ground.
But it is all I could make out of it, unless that screw hole a few centimetres in is infact not at ground potential?

[Noy]

Lower left Y-Cap connects 3. pad heatsink to PE (metal case connection / din rail).
Lower middle Y-Cap connects L/rectified L to PE (metal case connection / din rail).
Lower right Y-Cap connects GND/- to PE. <- has also connection to 1. / 2. pad from Heatsink..

There are no MOVS /TVS in the input path present currently. I watched some repair/advertising youtube videos for SITOP devices and every device has MOVS / TVS in it.
So probably MOVS/TVS places otherwise there are no overvoltage protection present in the input path of my device..

But MOVS destoryed and NTCs and fuse ok??


CORRECTION: THESE ARE CAPS! FOUND A PICTURE!
If you are looking through the case you can clearly see the whit - markings from 2 additional caps. I think the same like the other two..

Edit: But i don't get it..  no MOVS/TVS but NTC-> 2x Bulk -> CMC -> 2x Bulk ->"Transformer"

[Per Hansson]

Ok, that leftmost Y cap is strange that it connects from ground to ground, not sure what is up with that.
Anyway I did as you and looked on eBay, found the attached pictures from eBay auction 2 & 3, sure enough it is bulk caps!
I guess it would have been really illogical what I said in my previous post:
Because the 3-phase version will require less capacitance due to less dead time in the AC sine waves, not more!

Where you able to trace out and thus confirm my proposed circuit drawing?
I added a new one to this post because I found the missing component near the AC input was another X-cap, not sure where it connects to though.

[Noy]

Sorry currenlty busy so hadn't time to check.
But i checked the mosfets (i think the supply was used without heatsink a short time) they are fine also the 2 bulk caps are still fine (ESR, capacity) so i don't know why somebody should desolder the first 2 bulk caps. Will order some nippon chemicon ones from Mouser. Also build a new heatsink from 3mm steel :-D hadn't Aluminium. But i think steel should also work good enough, but its now really heavy and it was a lot of work to bend the steel.. Next time i will order Aluminium..

[Noy]

Its working again.. 2 new caps and a 3mm steel heatspreader "build"...