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

[jsteiger]

Hey Jeff,

Sorry for not responding for a bit, I got sick and ended up in the hospital. Things are getting better now. So I just finally got a chance to look at things. I think I know what the problem is. So when I'm checking the DCV on pins 1 and 2 of F3, 4 and 5 I can see the DCV on both pins 1 and 2. When I check on F2, there is no charge on pin 1 going to the led. I reflowed the solder on both pins just to be sure, but it's still not sending any power. And there is no DCV on R8. So am I right in guessing that pin 1 on F2 is most likely the culprit?

I would guess that the fuse in F2 is blown. Pull it out and check it for continuity. If a fresh one blows, there is a problem after the fuse to look for which is only the LED or a short with the header or something. There is really nothing following that fuse so you should be able to sort it out.

 

[Angryzen]

I feel like a freakin moron. I kept looking at the fuse thinking it was ok, but sure enough, swap it out and everything works. Thank you so much for the help, you taught me a lot about tracking down problems, and I think I understand more about how to trace circuits now. You rock my man!

 

[okgb]

A friend's capi 51x psu is occasionally blowing the 48v fuse during sessions ,
anyone know how much current the 48v regulator can handle if it is NOT heat sinked ?
or other avenues of investigation to solve this ? Tia

 

[jsteiger]

A friend's capi 51x psu is occasionally blowing the 48v fuse during sessions ,
anyone know how much current the 48v regulator can handle if it is NOT heat sinked ?
or other avenues of investigation to solve this ? Tia

Hey Greg, its a 0.7A part which we have fused at 160mA. Maybe there is a module acting up with an issue?

 

[Mishegas]

Hiya Hiya Hiya Folks!

ALMOST finished the PSU...except I'm a bit confused with the Neutrik to J1 connections (for a VPR) ...The Neutrik has 5 cups AND a ground terminal and the spreadsheet chart at the end of the assembly aid refers to 1 thru 5....? (Also I'm assuming the BUILD photo <http://www.classicapi.com/catalog/images/FB-build/FB-PSU-build-36.jpg> is the 51X version...or?)

I REALIZE that this question is borderline moronic ...but I rather ask than do something stupid....(I just spent half a day trying to figure out why my -16LED was not lit and after reflows, new sil-pads on the regs, bla, bla, it turned out to be a slightly loose fuse holder clip...)

Thanks folks!

PS...AWESOME quality kit!- I'm replacing a BAE with this- the difference in materials is really stunning...

 

[jsteiger]

Hiya Hiya Hiya Folks!

ALMOST finished the PSU...except I'm a bit confused with the Neutrik to J1 connections (for a VPR) ...The Neutrik has 5 cups AND a ground terminal and the spreadsheet chart at the end of the assembly aid refers to 1 thru 5....? (Also I'm assuming the BUILD photo <http://www.classicapi.com/catalog/images/FB-build/FB-PSU-build-36.jpg> is the 51X version...or?)

That pic is showing a 51x cable and PSU. The VPR will have 2 less wires. Use the table near the end of the assembly guide. The #'s listed 1-5 under the Neutrik heading are referring to the small #'s printed in the plastic of the Neutrik connector. The wire #'s to use are on the far right. I highly recommend following that chart AND double checking your voltages at a card edge connector in the rack (with no modules loaded) to verify that you have everything wired up properly.

 

[Mishegas]

The #'s listed 1-5 under the Neutrik heading are referring to the small #'s printed in the plastic of the Neutrik connector. The wire #'s to use are on the far right. I highly recommend following that chart AND double checking your voltages at a card edge connector in the rack (with no modules loaded) to verify that you have everything wired up properly.

Forgive my continued confusion, but I'm still befuddled by the 5 numbered "cup" terminals PLUS a ground terminal on the Neutrik-(that's 6 connections on the jack) 

Do I ignore the center/top ground terminal and just solder to the #'d terminals on the Neutrik?

OR in other words- do I solder wire #'s 1 thru 5 to the corresponding # cups on the jack ?

thereby ignoring the green ground wire and #6 - as well ignoring as the ground terminal on the Neutrik?

If all the above is true -then I'd  just hook up to the terminal block as described in the table (?) I.E.:
Chassis = #1
Ground = #2
+16        =  #3
-16          = #4
+48        = #5

I don't mean to be numbingly literal but that's how they wired *me*....

Thanks for the help Jeff!

 

[jsteiger]

By all rights, the connector's shell lug should go to the chassis pin. The numbers in my chart refer to what is printed on the connector. Nothing more, nothing less. Kinda straight forward.

 

[Mishegas]

By all rights, the connector's shell lug should go to the chassis pin. The numbers in my chart refer to what is printed on the connector. Nothing more, nothing less. Kinda straight forward.

Thanks Jeff,

Again, sorry for my confusion,  I've never dealt with a  5pin jack before , or building a PSU for that matter!

Since this is connected to the mains I suppose I'm being little over-cautious....(maybe not?)

Cheers to you!

 

[okgb]

My Friends 48v fuse problem seems to be the 7pin cable , so far good once he swapped  it out with another,
connectors look o.k. seems unlikely there is an internal break  ...................standing by.

No go , after powering up & down multiple times with no problem and left on for days ,
the 48 fuse went randomly sometime when the unit was on but not being used.
He did check the current draw and it was well under the fuse rating .....................so

 

[shockadd]

Hello list -

I've just completed the build of this dual VPR version and am finding that all the 16 volt  output voltages are at 10.3 volts and will not adjust with the multi turn trim pots.  The phantom power is at 32 volts and will not adjust as well. 

I've tested each resistor before installation, taken my time and double checked everything.  This is by far not my first kit build so Iam wondering what the problem is.  Like I said I was very thorough with this build and everything is correctly installed for the dual + - 16 volt supply version.
Anyone ever seen this issue before?? Did I end up with the wrong xfrmr??

Thanks and hope to hear from someone as I have two completed pres that I would really like to use...

DDD

 

[[silent:arts]]

My guess: you are in 115V mains-land and wired (or switched) the PSU transformer for 230V?

 

[shockadd]

My guess: you are in 115V mains-land and wired (or switched) the PSU transformer for 230V?

After having coffee, looking at xfrmr schemo  I came to same conclusion... although  my mistake was that I was looking at the pics of the new IEC and wired the switch correctly, but upside down... 

Gah.... tail between legs now...

DDD

 

[aud2go]

I just attempted to build a 51 x power supply .
I took a my time with it including heat sinking diodes and power transistors.
When firing it up,  48 volt and +16,  work fine -16 shows  24 volts and is  unadjustable and the two 24 volt rales are completely unadjustable as well.  I've double checked my work everything seems to be wired properly but I can't figure it out.  I did have some trouble identifying color codes on resistors ( vision issues) so that may be one potential issue but they look the same as the build picture from Jeff.
        What did I screw up?

 

[jsteiger]

I just attempted to build a 51 x power supply .
I took a my time with it including heat sinking diodes and power transistors.
When firing it up,  48 volt and +16,  work fine -16 shows  24 volts and is  unadjustable and the two 24 volt rales are completely unadjustable as well.  I've double checked my work everything seems to be wired properly but I can't figure it out.  I did have some trouble identifying color codes on resistors ( vision issues) so that may be one potential issue but they look the same as the build picture from Jeff.
        What did I screw up?

To clarify, I checked your order and you purchased the Dual VPR version not the 51x version so all four main voltage rails should be 16V not 24V.

Maybe post a pic or 2 of the PCB so we can dbl check your R values by color code. If you can't read the color codes then measuring them with your DMM is the best method. This cannot be done now that they are soldered in.

 

[aud2go]

  Yes I know but the power supply says 51 X on the front of it my biggest problem was identifying resistors because they are labeled on the schematic as follows "12K2" I was not taught to Reed resistors in that fashion so I have a hard time identifying and testing values so if you give me value corrections can you give them by color code please I can only post one photo per response so let me know what else I can provide to you thanks

 

[jsteiger]

What front panel do you have? It sounds like I might have sent you the wrong front panel.

For a Dual VPR build, R4 and R6 need to be 2k43. Its hard to tell in the pic but they look like they might be 3k92?

This is only for the LED's but R8 and R9 should be 1k5 for a Dual VPR build and it looks like they are 2k21. It will only effect the brightness of those 2 LED's so first things first.

Besides the above, it looks like the components are placed properly so I am gonna guess there are some bad solder joints somewhere.

 

[aud2go]

I don't understand how 2k43  is a number displayed on the digital multimeter is it 2,043 or 2,430  I'm not to clear as to how it is displayed. This is why I had so much trouble in the first place. I will check my solder joints but I'm pretty good with that.
I do a boatload of soldering. Just confused  on reading values.
Thanks

 

[[silent:arts]]

2K43 = 2430Ω = 2430R = 2,43KΩ etc

 

[4D Audio]

Hi everyone,

I am brand new to GroupDIY. Decided to take on this project as my first build. Initially, when testing the PSU about 10 days ago, everything tested fine, and I thought I had miraculously completed my first build without any major mishaps. Seems I was wrong. I finished putting together the eleven rack today, and upon turning the PSU on for testing I noticed the +48V Led no longer lit. None of the readings on the rack were accurate, so I opened up the PSU for further testing. Noticed that my multimeter no longer reads 48V on either of the JP1 48V terminals, but instead reads -16V. All of the other JP1 terminals seem to be testing accurately. Also noticed (not sure if this matters) that the longer Led leads all read around 20V except for the 48V Led lead, which reads around 16V. I've attached a picture.

Hope I've done a decent job of explaining the problem. If anyone can offer any guidance or suggestions it would be greatly appreciated! Thanks.