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Power ratings and 4 A per kWQuick one. How many amps does a 3 kilowatt immersion draw?
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Working out current from an appliance's power rating is how you size protective devices and cables in domestic installations.
How much current does a 10,000 W cooker draw on 230 V?
I = P ÷ V = 10,000 ÷ 230 = 43.48 A
Later this feeds into choosing a cable's CSA (cross-sectional area). That depends on the current, but also on the cable's length and how it's installed.
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- Building Regs
- PAT
- Fundamental Inspection & Testing
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