Something like that. I was thinking of cutting the PSU boards. Basically cutting 4 filter caps. 2 on each side of one PSU. Its gonna be a mess Im sure but possible Or create my own board with easyeda.
These are 500VA each I have one below deck too... 😀 (~170mm dia. x 80 mm H each)
The caps are 80V, 10,000uF
The first power supply picture seems to show a spacer for the xfrmr leads under the shield. It looks like Baltic birch to me, but could certainly be something else. The second picture showing the two xfrmrs doesn't seem to show it, but rather some sheet or plate metal between the two
Daniel, to avoid the transfer of mechanical vibrations to the chassis you could even consider placing the plate supporting the transformers on four rubber feet, the ones with screw mounts on both sides. I did that for a tube amplifier once. It doesn't prevent air-transmitted humming, but it does avoid your chassis humming along with the transformers.
Some progress... awaiting the psu boards. Transformers mounted. Was thinking about a sligthly elevated psu but still need to find a simple solution for the input snubbers if I want them.
Hi Kokkie,
Thanks, I will keep this in mind ordinarily I use a rubber disc under the transformer.
For what it is worth I loaded these to full capacity and the mechanical noise was extremely hard to hear with my ear next to the transformer.
- Dan
I see that you got your transformers from Poland. Are you happy with these toroids? Could you tell how much you paid for these and how much shipping to Australia cost? It's expensive to get heavy items from China and Poland is much further away.
Thank you,
cheers,
Question about the input earthing connection between the backplane and the main chassis plate. Is it best practice to "wire" the backplane to the main chassis plate or is that pretty useless in terms of minimising the resistance?
ok... the input grounds are tied together and then with a small cap connected to the backplane of the chassis. The anodized backplane is screwed to the chassis rails. The question is whether or not I need to assure the connection between the backplane and the metal chassis plate to which I connect the mains earth?
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The capacitor from shield to ground is just an EMI ground. You may or may not need it. The mains ground should be a real safety ground. The aluminum panel fastening screws are probably adequate for the safety purpose. You can try measuring the resistance with a meter that will do 4-wire ohm measurements in the milliohm range. If there is too much resistance (>50 milliohms maybe) try scraping or sanding the anodization off at the mechanical connection points. You could also try external star washers between the panel and the frame. If you are really paranoid, you could use a small amount of Noalox, which is used in aluminum to copper connections in house wiring (note that aluminum wiring is generally prohibited in many jurisdictions after starting numerous fires due to improper connections).
Some cabling progress....still awaiting the PSU boards. Can't wait to start firing up the tests. I found this variac. Would that deliver suffient power to complete the Wolverine tests or do I need a slightly more powerfull one?
