Accuracy of microprocessor earth fault protection systems depends on quality of the earth-fault current transformers. Ferranti earth-fault current transformers type I0 ensures an accurate measurement of earth fault currents in medium voltage power network different kinds of cables and busbars. Our earth fault current transformers are able to cooperate with almost any kind of microprocessor earth fault protection systems.
Full range of sizes and shapes
Devided and non-devided core versions
Test winding
Standard gear ratio 1:100 (custom versions available)
IO type transformers can be divided depending on the execution into:
Transformers with non-devided core:
- IO-85-N (IO-10) - designed for mounting on a single three core cable with maximum external cable diameter of 80 mm, output terminals k1-l1, k2-l2,
- IO-100-N (IO-11) - dedicated for installation on single three-core cable with maximum external diameter of the cable 100 mm, output terminals k1-l1, k2-l2,
- IO-280-N (IO-14) - dedicated for installing into four parallel three-core cables of maximum external cross-section of working conductors 3x240 mm2 - output terminals k1-l1, k2-l2,
- IO-480-N (IO-15A) - dedicated for installation on busbar of 480 mm diameter - output terminals k1-l1, k2-l2,
- IO-695-N (IO-15) - designed for installation on a busbar with a diameter of 695 mm - output terminals k1-l1, k2-l2,
- IO-70x400-N (IO-17) - dedicated for installation on parallel three-phase cables or three single-phase cables of maximum external diameter 70 mm - output terminals k1-l1, k2-l2,
- IO-110x250-N (IO-12) - dedicated for installing into two parallel three-core cables of maximum external cross-section of working conductors 3x240 mm2 - output terminals k1-l1, k2-l2,
- IO-125x470-N (IO-13) - dedicated for installing into two parallel three core cables of maximum external crosssection of operating cores 3x240 mm2 enabling displacement of cables - output terminals k1-l1, k2-l2.
Transformers with devided core:
- IO-85-D (IO-20) - intended for installation on existing single three-core cable with maximum external cable diameter of 80 mm without removing the cable head - output terminals k1-l2, k3-l3,
- IO-100-D (IO-22e) - dedicated for installation on the existing single three-core cable with maximum cross-section of working conductors 3x240 mm2 - output terminals k1-l2, k3-l3
- IO-135-D - dedicated for installing into the existing single three core cable of maximum cross-section of working conductors 3x500 mm2 - output terminals k1-l2, k3-l3,
- IO-110x250-D (IO-12d) - dedicated for installing into two parallel three-core cables of maximum cross-section of working conductors 3x240 mm2 - output terminals k1-l1, k2-l2
- IO-125x470-D (IO-13d) - dedicated for installing into two parallel three-core cables of maximum cross-section of working conductors 3x240 mm2 enabling displacement of cables - output terminals k1-l1, k2-l2,
- IO-250x450-D (IO-16) - dedicated for installing into four parallel three-core cables of maximum cross-section of operating cores 3x240 mm2 or into busbars - output terminals k1-l1, k2-l2.