Miniature Screws Mounted Current Transformer SCT Series 0-5000A for Power Monitoring and Protection

The SCT series miniature screw-mount current transformer is designed for power monitoring and protection applications. The rated input covers 0-5000A with an output of 0-500mA.The product uses a screw-mount design. The internal window is large, allowing high-current cables or copper busbars to pass through directly. Installation is simple and fast.An internal precision resistor is connected in parallel with the secondary winding, providing a safe low-voltage output. This saves installation time and cost.Ratio accuracy: ≤±0.1%. Phase angle error: ≤±5 minutes. It meets high-precision measurement requirements.The housing is made of ABS/UL94-V0 flame-retardant material. The interior is epoxy potted. The core uses Permalloy or nanocrystalline material, suitable for harsh environments.It is widely used in power distribution systems, motor monitoring, lighting control, HVAC, and automation control systems.

• Rated input – 0-5000A
• Measuring range – 5%In to 120%In
• Rated output – 0-500mA
• Ratio error – ≤±0.1%
• Phase angle error – ≤±5 minutes
• Frequency range – 50-400Hz
• Dielectric strength – 2.5KV/1mA/1 minute
• Insulation resistance – ≥1000MΩ (DC500V)
• Housing material – ABS/UL94-V0 flame retardant
• Core material – Permalloy or nanocrystalline

• Power distribution system current monitoring
• Motor current measurement and protection
• Lighting system power monitoring
• Air compressor current monitoring
• HVAC systems
• Relay protection devices
• Power and energy monitoring equipment
• Automation control systems

Q: What is the ratio accuracy of this current transformer?

A: The SCT series offers ratio accuracy of ≤±0.1% and phase angle error of ≤±5 minutes. This is a high-precision class. It is suitable for power monitoring, energy metering, and relay protection applications that require high measurement accuracy.

Q: What is the single-turn feedthrough structure? What should be noted during installation?

A: The single-turn feedthrough structure means the measured cable or copper busbar passes directly through the centre window of the transformer. There is no need to wind coils around the transformer. During installation, ensure the measured conductor passes through the centre of the window for best measurement accuracy. The window size must match the measured cable or busbar.

Q: Why is the secondary output a safe low voltage?

A: The secondary winding is connected in parallel with an internal precision resistor. This converts the current signal into a low-voltage signal output (≤0.5V), ensuring the safety of operators and connected measurement equipment. This design also eliminates the need for external sampling resistors, saving installation time and cost.