Main electrical panel beside a subpanel with its cover removed

Reading an appliance rating label: volts, amps, watts and what they tell you

The rating label gives the supply the appliance needs and how much it draws. With a clamp meter and a little arithmetic you can tell whether the appliance is drawing normally, whether it is on the right circuit and whether a 208 V supply explains weak heat.

Single source ~15 min easyBrands: All

Before you start

Clamp measurements on live cords are caution steps: clamp one conductor only, keep hands clear of terminals
Do not open panels to read breakers; read labels from outside

Diagnostic steps

Unlock all 6 steps with expected values

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OnCall Tech is a reference tool for trained technicians and can make mistakes. Always disconnect power and confirm with the manufacturer's documentation before you work.

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