Current transformer: in the measurement of alternating current, in order to facilitate the secondary instrument measurement needs to be converted to a more uniform current (China’s current transformer secondary rating for 5A or 1A) . 

ARTU-M32 telemetry unit: THE TELEMETRY UNIT USES AC sampling to measure 32 channels AC/DC0 ~ 20 ma, AC/DC0 ~ 5V RMS, and exchanges data with upper computer through RS485 bus, a telemetry value that reflects the standard signal of a transmitter or sensor. Can Be Current, voltage, temperature, pressure and other transmitter analog output signals into digital signals and upload, with 32-way two-color LED lights, used to indicate each input signal of four states (no input, signal normal, high alarm, low alarm) , high alarm value can be set by communication.