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ct image)
The secondary load of a current transformer is termed the "burden" to distinguish it from the primary load. The burden in a CT metering circuit is the largely resistive impedance presented to its secondary winding. Typical burden ratings for IEC CTs are 1.5 VA, 3 VA, 5 VA, 10 VA, 15 VA, 20 VA, 30 VA, 45 VA and 60 VA.