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

[kante1603]

Thats a good idea. Also can I do 7 LEDS? 5 for the power indicators and two for the power. If so should I wire them parallel or series? and which one should I double up?

Daniel

Hello Daniel,

The additional leds for power are a bit overkill I think.
When the others are lit you can already see that all rails are working,therefore the unit must be powered on,no?

Best regards,

Udo.

 

[Bonsaimaster]

Its more visual than necessary.
Plus it looks cool!

 

[AudioGimmer]

Built up my PSU on Sunday

What a great kit, the fit of all the parts is great, and super easy to put together.

Fired up right first time, and voltages all trimmed to correct settings. Trickiest part was wiring the 7pin to the end of the multiway cable, not a lot of space in the pin's solder cups.

My soldering is pretty neat and tidy, but I struggle with dressing cable and wires as neatly as everyone else seems to.

Finished and ready for action:

Thanks to all the 51x team, especially Volker for making sure the kit was finally delivered [no thanks to Hermes....]

The Gimmer

 

[[silent:arts]]

[no thanks to Hermes....]

you should add how it arrived ...

 

[sharpeleven]

I'm relocating to Europe with two of Jeff's 51x floor box PSUs (already built and working great in US). Is it enough to just flip the voltage selector to 230V from 115V? Are there any other adjustments needed, eg. wiring, fuses, or am I good to go?
thanks!!

 

[[silent:arts]]

Just switch to 230V, and all is fine.

 

[technoteo]

Just finished to build the PSU from Volker, it was really easy and fun.  Iwas impressed by the quality of the materials and the way it's done. Great work!!

To check if I conected the trafo right I wired the out to a junction terminal to easily check the voltages.

Thanks Volker!

Now I'm waiting for 2 x VP28 and 2 x 312 from Jeff

 

[sharpeleven]

Ok, I'm building yet another 51x PSU  8) but this time it looks like I'm stuck...

Before first power up I figured it might be a good idea to check JP-1-1 for any continuity. Indeed there is continuity between GND/CHA and 48V and +24V. Same outcome with no DC cables installed.

I cross checked against one of my working 51x PSUs and there is no continuity there (expt of course btw CHA & GND). I also checked against any obvious signs, orientation, solder bridges, etc, reflowed all solder points but to no avail.

Any clues would be highly appreciated!

At one point during the build I had to de- & resolder  JP-1-1 cause it got accidentally installed in reverse orientation. Might that have damage the PCB?

thanks!!

 

[jsteiger]

I would check the voltage regulators for those sections. Did you use the silicon pads? Maybe they are too tight? Take those screws out and slightly pry those regs outward so they do not make any physical contact with the heatsink sides then measure DCR between the 48V and +24V headers.

 

[sharpeleven]

I would check the voltage regulators for those sections. Did you use the silicon pads? Maybe they are too tight? Take those screws out and slightly pry those regs outward so they do not make any physical contact with the heatsink sides then measure DCR between the 48V and +24V headers.

Thanks, Jeff, you da man! Indeed it was the regulators. Loosening and reseating them did the trick - problem solved. Thank you!!! 

 

[jsteiger]

Great. They need to be nice and snug but over-tightening them can spell trouble.

 

[theokbird]

I bought a dual VPR (+16v, -16v) kit , however can i simply convert this to the 51x version(so i can accommodate 24v rails in the future if i want)  just by using the alternate resistors in my kit?

 

[jsteiger]

I bought a dual VPR (+16v, -16v) kit , however can i simply convert this to the 51x version(so i can accommodate 24v rails in the future if i want)  just by using the alternate resistors in my kit?

No you can't. That would require a different toroidal transformer as well as changing the 4 R's.

 

[theokbird]

Ah right, thanks!

 

[technoteo]

Here is a little trick I used to keep in place the headers

I cut a piece of this puzzle foam so that can be placed between 2 connectors

and then...

the foam is the one used for kids, I use this also under my Tannoy monitors 

 

[mdmitch2]

Finished a vpr psu / rack a few days ago.... everything went smoothly, except one LED was out. I found that the fuse was not making a good connection. Apparently when I first put it in, I didn't push it in squarely, and it bent one end too widely, so it wasn't clamping down on the fuse. I bent it back with some pliers... problem solved.

Fun build 

 

[brewbacca]

I have a pretty fresh dual VPR PSU with a single VPR 11 rack that happened to fill up rather quickly. I added a couple Don Classics U67a's and started having a bunch of problems. I checked the voltages on my PSU and the +16 was around +10. When I unplugged the power supply from the rack, it went back to ~+16. I tried plugging in the other cable (V2), and the voltage on that is around 15.9V now (both +/- while plugged in). I would assume a slight voltage drop isn't that weird for a full rack, but for the first channel, could it be that  messed up the LM350T for +16? 6+ volts seems like something is broken.

 

[jsteiger]

Under full and proper load (no more than 1.5A per rail) the Floor Box PSU will sag no more than 250mV or so. Something definitely sounds wrong. Maybe that reg is too tight and nearly shorting thru the sil pad? You could remove the screw and slightly pry it away from the heatsink side and see if the problem continues.

I have seen guys forget to solder all the pins on the regulators. That can be a major issue as well.

 

[brewbacca]

Yup, looks like IC5 was too tight. Loosening it up a bit definitely helped. Thanks Jeff!

 

[Vac11]

Maybe a beginner´s stupid question... It is also possible install the floor box PSU into rack? If so, how? Thanks ... M.