The old-fashioned way would be to look up how much amperage is used for each component and then add up the total. The specs should be in the owner’s manual and/or the back plate. The amperage will increase for the amps during playback - so select the maximum draw as per the owner’s manual.
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Watts = Amperage x Voltage. This formula will help figure out the amperage if it’s not listed. How’s your algebra?
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- Ideally, from an electrical perspective, the same amount of amperage should be on each separate circuit - to keep the legs (phases) balanced. It’s highly unlikely that anybody actually does this in their home - and it’s not dangerous with a good utility panel installed. Balanced phases are used primarily in industrial/commercial installations. (Balanced phases vs Balanced power are two completely different applications.)
- Ideally, from an audio perspective, the digital components should be on a separate circuit than the analog components. Or they can be separated via a power conditioner if a circuit is to be shared.
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meaning drawing current from one outlet will drain the other two.
It doesn’t work that way. Neither the current (amperage) - nor the voltage - will be affected as long as the load is under the circuit rating. If the load is over the rating, the voltage may reduce and the wire itself will get warm to hot - depending on the load. The circuit breaker should trip if the load the load is too high - thus preventing any electrical fires.
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