How thick of a copper plate is needed for 220V and 3 amp current flow? How do I calculate it?
Answer: This depends on the the width and length as well. Once the allowed voltage drop and the width is known the thickness can be defined. The resistivity of copper at 20C is 1.68 e-8 ohm m. The net resistance is 1.68 e-8 * length (m) / cross sectional a
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