The 390V are the output of the PFC stage, so by definition they have the same (or slightly higher) power as the 12V and 24V outputs together. And it is regulated (more or less), with only a slight ripple of twice mains frequency.
What it is not: Isolated. Like putting a rectifier on the mains (only with more volts). Not good for audio, makes speaker posts and cinch connectors lethal, even in a wood chassis!
What it is not: Isolated. Like putting a rectifier on the mains (only with more volts). Not good for audio, makes speaker posts and cinch connectors lethal, even in a wood chassis!
That's why I'm using an isolation transformer. See post #6.
Does this fully address the issue?
Does this fully address the issue?
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If this is true, it should be isolated. Make sure you check with a good ohmmeter, not just a go/no go electrician's tester. Some supplies have a current sensing resistor in the output negative line, so a non-isolated supply may show some resistance.
An isolated supply should read infinite.
Adding an isolation transformer does take care of any isolation issues, but it defeats the purpose. The purpose of these supplies is to avoid a transformer in the first place
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I checked using the continuity beep function on my ohmmeter, but good point- I'll check just using the resistance reading. Your right, I think anything above a few ohms might not beep, but it certainly doesn't mean isolated.
But doesn't using an isolation transformer provide the safety isolation regardless?
But doesn't using an isolation transformer provide the safety isolation regardless?
If this is true, it should be isolated. Make sure you check with a good ohmmeter, not just a go/no go electrician's tester. Some supplies have a current sensing resistor in the output negative line, so a non-isolated supply may show some resistance.
An isolated supply should read infinite.
Adding an isolation transformer does take care of any isolation issues, but it defeats the purpose. The purpose of these supplies is to avoid a transformer in the first place
Isolation
I made this video, testing continuity between the 120V AC input side, and the 380VDC. Blue wire is 0V, Brown is 380V.
My Movie - YouTube
Interpretations?
I made this video, testing continuity between the 120V AC input side, and the 380VDC. Blue wire is 0V, Brown is 380V.
My Movie - YouTube
Interpretations?
New Developments: Grounding Question
I made some more progress. See pic. It's not all hooked up yet, but I have tested some components. It's getting slightly bonkers just for a preamp supply, but that's part of the fun.
I had a 24V dc/dc converter and ripple attenuator laying around that was collecting dust, so I decided to employ that for the heaters. We'll see how it works! I did a quick test of it, and it looks like about 2mV of ripple at 200KHz or so. Can pick them up real cheap on ebay.
http://www.vicorpower.com/documents/datasheets/ds_vi-ram.pdf
Also, I got a 21st Century Maida regulator from Neurochrome for the HV
SOME QUESTIONS:
It's been determined that the 380V (-) is not connected to earth, but it is connected to the negative of the diode bridge of the PSU. Hence, I'm using an isolation transformer.
I'm thinking because of the switching modules, I should separate the earth and signal ground via a resistor/cap/diode decoupler as has been suggested for years on many pages here.
Where do I connect the (-) from the 380V PSU to this signal ground? See attached pdf sketch for how I was thinking to do it. Comments?
I made some more progress. See pic. It's not all hooked up yet, but I have tested some components. It's getting slightly bonkers just for a preamp supply, but that's part of the fun.
I had a 24V dc/dc converter and ripple attenuator laying around that was collecting dust, so I decided to employ that for the heaters. We'll see how it works! I did a quick test of it, and it looks like about 2mV of ripple at 200KHz or so. Can pick them up real cheap on ebay.
http://www.vicorpower.com/documents/datasheets/ds_vi-ram.pdf
Also, I got a 21st Century Maida regulator from Neurochrome for the HV
SOME QUESTIONS:
It's been determined that the 380V (-) is not connected to earth, but it is connected to the negative of the diode bridge of the PSU. Hence, I'm using an isolation transformer.
I'm thinking because of the switching modules, I should separate the earth and signal ground via a resistor/cap/diode decoupler as has been suggested for years on many pages here.
Where do I connect the (-) from the 380V PSU to this signal ground? See attached pdf sketch for how I was thinking to do it. Comments?
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