[BUILD] CAPI Dual VPR & 51x Floor Box PSU~Official Support Thread

[jsteiger]

No, there must be something else wrong with the build. I would keep looking.

 

[nolivdacom]

All right!
I check again an again! And now it's working!  8)
I think it was about the 7 pin connector on rear of the rack which was to tight against the chassis or PCB's rack...
I didn't find any short circuit or impedance problem with my tester... never trust it! I lost +16V rail because of leakage current at this connector. I think the +16V regulator didn't work really fine too...

Anyway, thanks a lot for your help and congratulation for this great gear!
Thanks Volker for the candies!

 

[nolivdacom]

more pictures!!!

 

[nolivdacom]

7 pin connector...

 

[BajenKeno]

So I opened one of the bags and these little fellas decided that the floor was a interesting place to visit!
First I tried to figure out what they are (some kind of spacer I presume) and then I tried to get some info on how many the bag was supposed to contain. Failed at both!

So my question to you good people is, what are they and how many am I supposed to possess? (I got 5 atm).

Regards, Simon.

 

[warpie]

well, you found them all I guess 

http://www.classicapi.com/catalog/images/FB-build/FB-PSU-build-11.jpg

 

[AdamWillden]

Firstly, many thanks to Cemal for his email support and Group 51X generally for the fantastic quality product (and instructions). First thing I've tried doing DIY and now will be hooked like the rest of you!

Secondly I'm posting here in case someone was a numpty like I:

• Read though this thread first and make sure you have the transformer primaries correctly wired (especially for EU residents)
• Use a slow blow fuse at the mains end (voltage selector compartment) - fast blow will blow intermittently and make you think somethings wrong when you're build is actually fine!
• To check for continuity between IC tab and chassis remove the gnd/chassis loops first. Without doing this IC2 & IC4 will appear as though they're shorting to ground but that's due to the schematic/IC pinout:
  
  IC middle pin == same as tab == Vo == Connected to ground for IC2 & IC4 == appears to have continuity with the backplate

Basically I had my primaries wrongly wired then ended up chasing my tail for a second non-existent problem due to using a fast blow fuse.

 

[Unit7]

Maybe I'm being punished by higher powers for thinking I got the PSU built right at first attempt, because now - after connecting the cables to the racks - all of a sudden the mains blows at every power up. All fuses on PCB intact, so hopefully Adam's tip about getting a slow fuse for the mains will fix the problem. Gonna check that tomorrow, Meanwhile perhaps someone could reply if my readings seems ok when measuring the primaries of the transformer? Measured in series (for 230V), just like it was wired two days ago when everything was ok and I was able to trim 16V, 24V and 48V, I get just north of 9Ω.

 

[kante1603]

Hi Paul,

if it happens again with a slow blow fuse try it with an empty rack.This way we can sort out if it is rack- or module related.
Do you drive one or two racks?
How many and which modules are inserted?
Did the modules work already,maybe in another rack?
Since the psu did work already some days ago it can't be too hard to find.
If it works with an empty rack insert one module after the other and see what happens.
Btw.,only the mains fuse blew up?
Did it blow immediately or after say some seconds?
This could indicate either a short ( somewhere in the rack) or generally too much power by inrush current.

Let us know,

best,

Udo.

 

[Unit7]

Thanks Udo!
Just bought slow 1.25A fuses. Gonna test tonight. Meanwhile:
Only mains fuse blew, and immediately at power up.
All fuses on PCB ok
It's a dual PSU
No modules in racks.
Tested also without racks connected - no success
Measured for shorts yesterday night. Couldn't find anything obvious, but 'pinged' on the mains (live/neutral) and got a 9.2Ω reading and just wanted to check if that seems ok.
Anyway, keeping my fingers crossed that the new fuse will fix it…

 

[[silent:arts]]

I measure 4,5Ω on each primary winding - 9,2Ω for 230V sounds fine.

 

[kante1603]

I measure 4,5Ω on each primary winding - 9,2Ω for 230V sounds fine.

Same here!
Udo.

 

[kante1603]

Me again,

does that mean this happens even when nothing is connected to the psu?
If so and you saying it worked some days ago I tried to think logical.
What has changed then-yes,it might be a mechanical thing,maybe a wire forced down,maybe a solder joint becoming loose or short to metall,and something else:
Does the mounting screw going through the center of the transformer eventually touch the top lid?
If so it could cause a magnetic short (1 winding).

Maybe you can post some pics of your build.

Just thoughts,but who knows what it's good for....

Good luck and let us know,

Udo

 

[Unit7]

Udo, you're too kind! Really. Thank You.
Success here! The new slow fuse seems to have made it, knock on wood...
PSU sealed and ready for my studio.
Excuse me for taking your time when everything was ok.
This kit needs a sticker for the mains on the backside, like: Fuse: US Slow 2.5A/EU Slow 1.25A

 

[kante1603]

Great!

Hopefully it really was a crappy fuse (imagine me searching for wood to knock on too,hahaha....).

Best regards,

Udo.

 

[electroshift]

Hi folks, I recently finished my PSU and everything seems to be working fine. Many thanks to Jeff for having such a great product and setting up this thread for documentation. I was a bit weary of having the cables attached to the PCB, even with the fasteners, so I performed the little mod shown in the attached picture. Pretty self explanatory change, I just need to buy the extra connectors to finish it

Cheers,
Rafael

 

[[silent:arts]]

Cool. And I thought I'm the only one with this mod ;-)

 

[mulletchuck]

the old PSU came with 7-pin XLR connectors.  I'm surprised this build didn't; it seems like a commons sense design choice...

 

[jsteiger]

the old PSU came with 7-pin XLR connectors.  I'm surprised this build didn't; it seems like a commons sense design choice...

The choice of using the Heyco cord grips was customer driven. Folks were wanting a lower cost PSU solution so an easy thing to do was eliminate 2 panel mount 7-pin XLR's and 2 cable mount 7-pin XLR's. That drops a dual cable build by about $44.00. That is common sense.  8)

If someone wants this, as seen above, it is easy to do, not to mention, this is still DIY. 

 

[[silent:arts]]

If someone wants this, as seen above, it is easy to do, not to mention, this is still DIY. 

yes it is  ;D ;D ;D