Linear PS with no ground pin

[McQuaide]

Hi all,

I just finished building a Pass DIY Phono preamp (actually two, one for each channel), and I'm looking at ways to power it. It requires +28-34v, ground, and -28-34v connections. I tested the boards with 6 9v batteries in series, with ground connected at the midpoint, and they work well.

So I purchased this PS: Power Supplies, Power Supply, Bench Supplies, Transformers

Unfortunately there's no ground connection on the supply, and I can't locate a schematic for it. Any ideas for using this particular supply with my project? Or is it a writeoff?

Thanks

 

[DF96]

That appears to be a 28V supply, which will give you 0 and +28V. Not what you need.

 

[McQuaide]

That appears to be a 28V supply, which will give you 0 and +28V. Not what you need.

OK, that's what I thought. Live and learn

The instructions for the preamp say wall warts can be used. I assume I could connect two 30v wall warts together in the same way I connected the batteries?

 

[DF96]

If their outputs are isolated from the mains, then yes. This will probably be the case.

Why not buy or build a proper power supply?

 

[McQuaide]

If their outputs are isolated from the mains, then yes. This will probably be the case.

Why not buy or build a proper power supply?

I was hoping to buy rather than get into another project at this time. Anything you can recommend? The Pearl 2 already has voltage regulation and filtering (doc here) http://www.passdiy.com/pdf/PEARL 2.pdf

Thanks for your advice.

 

[McQuaide]

Here's another thought. Since I already invested in the PS, I could just buy another of the same model, and connect them in series with the midpoint going to the ground.

 

[DF96]

If the output is isolated.

 

[McQuaide]

If the output is isolated.

I can't tell if it is or not. Can you tell from the photo and data sheet linked below? Thanks again.

An externally hosted image should be here but it was not working when we last tested it.

http://dl.dropbox.com/u/370002/PS%20data%20sheet.pdf

 

[Frank Berry]

The power supply has an isolated output.
You can safely use two of them to create a bipolar supply.
Connect the - of one supply to the + of the other supply.

 

[McQuaide]

The power supply has an isolated output.
You can safely use two of them to create a bipolar supply.
Connect the - of one supply to the + of the other supply.

Thanks.

 

[DF96]

Sorry, I tried to look but for some reason I could not get the pdf.

 

[McQuaide]

Sorry, I tried to look but for some reason I could not get the pdf.

NP thanks for the help.