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My meter is measuring 0A and 0kW but correctly reads the Voltage, what’s wrong?

If the meter is being provided a very small current (0.005A/5mA or less) on the secondary side, the meter will read 0 for the phase current.
Since kW is dependent on the current reading this value will also be zero.

To find out what the minimum Primary starting current is you can calculate as follows:

Primary_Min_Current = 0.005 * CT_Ratio

Where CT_Ratio = CT_Primary/CT_Secondary


CT Ratio = 2000:5 (Primary:Secondary)

Starting Current = 0.005A (Secondary)

CT_Ratio = 2000/5 = 400

Primary_Min_Current > 0.005 * 400 = 2A (primary side load).

Original article#16720

Last Revised: June 22 2007


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