Beckhoff SCT Series Documentation page 20

Product overview
Ring-type current transformer for differential current measurement
Fig. 11: SCT5xxx
The increasing prevalence of DC loads (e.g., LED lighting, DC motor drives, 48 V DC bus systems, etc.),
distributed DC generation (e.g., PV systems, UPS, batteries, etc.), and high-frequency converters (e.g.,
SMPS, motor drives, etc.) in industrial environments makes it increasingly difficult to reliably measure
insulation faults with conventional current transformers designed for AC 50/60 Hz with limited measurement
bandwidth.
Differential current transformers of the SCT5xxx series can be used here. Monitoring residual currents with
the SCT5xxx in real-time in a power system opens up the possibility of evaluating the condition of the
electrical insulation based on the actual measured value, so that the long-term trend of the residual current
value can be used for planning maintenance to detect significant deterioration of the insulation.
This means that residual current monitors (SCT5xxx) used in a condition-based monitoring scheme Industrie
4.0-Standards, can detect faults in a timely manner and increase the availability of power supplies or plants
at a much lower cost than conventional, expensive, and time-consuming high-voltage insulation testing.
Ring-type current transformer for differential current measurement
Measuring ranges 400 mA / 2 A, type B / B+, transformer opening 70 mm
SCT5564
20 Version: 1.0 SCT5xxx