The Dent Instruments CT-HSC-020-U 20A Mini Current Transformer is a small, low cost current transducer with high accuracy over a wide dynamic range with excellent phase shift. The "mini's" are ideal where space is limited such as when metering multiple loads within a panel board. Use for current measurement, energy metering, load surveys, demand metering, energy research, and sub metering. Ratio Error: <0.5% from 0.25 to 26A AC, Phase Error: <1.5 degrees from 1 to 26A AC, <2 degrees from .25 to 1 A AC .