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Tubelab SE build and power supply questions.

Yes..try to run all of your grounds to one ground point..."star" ground. Including the mains ground on the power cord.



One of the transformer mounting bolts is a great place....and ring lugs are also a great choice, with star lock washers in between the lugs to get a good bite in the ring lugs and the chassis.
 
Re-reading your question above ....I think I misunderstood what you were asking........If you are going to ground the grey "shield" wire from the transformer, don't also run another redundant ground wire from a transformer screw to your ground point....you are setting yourself up for a ground loop issue, which can result in noise/hum.


Convince yourself that the grey shielded wire is a ground wire in the transformer by checking for continuity between the grey wire and the transformer case/mounting feet etc, then just connect that to your star ground stud.
 
Re-reading your question above ....I think I misunderstood what you were asking........If you are going to ground the grey "shield" wire from the transformer, don't also run another redundant ground wire from a transformer screw to your ground point....you are setting yourself up for a ground loop issue, which can result in noise/hum.


Convince yourself that the grey shielded wire is a ground wire in the transformer by checking for continuity between the grey wire and the transformer case/mounting feet etc, then just connect that to your star ground stud.

Ok, that makes more sense!

Another quick question. The manual says to "Check all exposed metal for less than 1 ohm of resistance to the center terminal of the power connector" as part of the checklist before applying power to the unit. What exactly is considered the center terminal of the power connector?
 
It's the mains ground....if you have a three prong plug on your power cord, check for less than 1 ohm resistance between any exposed metal chassis part and the ground pin on the three pronged plug.


Use the milli-ohms scale on your meter if you happen to have one...otherwise just ohms.


If high voltage DC from the power supply or tubes or whatever happens to contact the chassis metal, you want a direct low-resistance path to your house ground so that the circuit breaker pops.
 
It's the mains ground....if you have a three prong plug on your power cord, check for less than 1 ohm resistance between any exposed metal chassis part and the ground pin on the three pronged plug.


Use the milli-ohms scale on your meter if you happen to have one...otherwise just ohms.


If high voltage DC from the power supply or tubes or whatever happens to contact the chassis metal, you want a direct low-resistance path to your house ground so that the circuit breaker pops.

Thanks!