I've built a couple of preamps and amps. The way I do the grounding scheme:
I keep the chassis ground and signal ground separate.
All panels in the metal chassis conduct with each other and I connect a metal tab to a bolt near the IEC and run a short wire to the ground pin.
The RCAs, binding posts, etc. are all insulated and only connected to the signal ground. Signal ground is in a star ground configuration.
Power supply is a very simple design where the transformer has two secondary windings and the center tap is grounded to the star ground (signal).
If I take an Ohm meter and measure AC between let's say one of the RCA connectors (ground) and the chassis, I get anywhere from 25VAC (amplifiers) to 50 VAC (preamps). DC between the two grounds is practically zero.
The systems work perfectly.
Should this cause for a concern? Is it improper to keep the two ground separated?
Thanks for all of the help!
I keep the chassis ground and signal ground separate.
All panels in the metal chassis conduct with each other and I connect a metal tab to a bolt near the IEC and run a short wire to the ground pin.
The RCAs, binding posts, etc. are all insulated and only connected to the signal ground. Signal ground is in a star ground configuration.
Power supply is a very simple design where the transformer has two secondary windings and the center tap is grounded to the star ground (signal).
If I take an Ohm meter and measure AC between let's say one of the RCA connectors (ground) and the chassis, I get anywhere from 25VAC (amplifiers) to 50 VAC (preamps). DC between the two grounds is practically zero.
The systems work perfectly.
Should this cause for a concern? Is it improper to keep the two ground separated?
Thanks for all of the help!
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For safety the two grounds should be connected together. For low hum this should be in one and only one place.
But if these two grounds are not connected, is having such high AC voltage pretty normal?
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