October 9, 2013

New DC Immune Split-Core CT by Ball-effect Technology (KEPCO has replaced existing Smart Meter with all-in-one CT & PT Smart Meter)


A successful example is the case of Korean Electric Power Corporation (KEPCO). KEPCO chose the latest J&D model as a key component when installing solid state type electronic watt-hour meters. KEPCO has replaced existing meters with all-in-one CT meters to solve power theft and safety problems and the cost increase when connecting an outer mounted. CT and metering outfit of a 5A watt-hour meter. The new solid state watt-hour meter adopted J&D’s split-core CT which meets the standard of IEC62053-21 in open-type with DC Immune CT. There is no need to cut off the power when replacing the meter, resulting in economic installation. The open-type CT with DC Immune has solved the problem of without DC Immune split-core CT, by using the principle of a Hall-effect element and Rogowski coil technology. It cannot be applied to existing 5A smart meters, thus developers should redesign in order to apply it to smart meters.

Hall-effect technology of with DC Immune split-core CT requires that the primary current passes magnetic core first. The primary current induces an initial magnetic field, and generates a voltage which is proportional to the primary Hall element. The amplified voltage is converted into a secondary current, which generates a voltage at the output position. It complies with the standard of IEC60044-1 with 0.5S and 1 Class, and can measure the AC/DC range of 100-2,400 A. In addition to this, it satisfies with inner diameter of 24, 36, 35*38, 62*73, 62*141 mm. The main application areas are DC meters, AC meters, and AC/DC combination meters. The technology is also used in other applications including PV monitoring, motors, inverters, rectifiers, UPS, welding equipment, and throughout the railway industry.