Type B summation current transformer for mixed-frequency RCD applications
The Siemens SENTRON 5SV8701-2KP is a Type B summation current transformer designed for use with residual current devices (RCDs) in AC and DC systems. Its 35 mm internal diameter accepts bundled conductors up to that cross-section, and the 80 A rated operational current covers most sub-distribution and machine feeder circuits. The 10 mA minimum residual current sensitivity means it can work with high-sensitivity RCDs down to 10 mA, while the 2.5 VA apparent power consumption keeps the burden on the RCD low. The metal shielding reduces external field interference, which matters when the transformer is mounted near busbars or power supplies.
The 5SV8701-2KP measures 79.2 mm deep by 99.5 mm wide by 55 mm high, fitting into a standard distribution board footprint. The plug-in terminal connection accepts up to 6 x 0.75 mm² conductors, and the maximum wire length to the RCD is 10 m — keep that in mind when routing the secondary wiring.