instrument transformer / current / encapsulated / toroidal
toroidal, DIN rail mount, wall-mount
Max.: 4,000 A
Min.: 1 A
The TCB's different characteristics are fixing system: to wall, to cable/passing bar or to DIN rail by accessories supplied with the CT, Measuring Transformers: the short circuit on terminals or the connection to earth can be achieved by the double fast-on or connecting two wires on the same terminal. And Protection Transformers: the C.T. when used as a current generator for protection relays has electrical characteristics which differ from those of the measuring transformer. Infact the measuring C.T. is expected to give a saturation of the magnetic circuit with 5P in primary currents while, in the case of protective C.T., it is necessary for the secondary current value to follow the increase in the primary current up to 10-15-20 In, so as to guarantee the intervention of the relay in the case of unforeseen breakdown current.