YHDC SCT019 Split Core Current Transformer User Manual

1. Introduction

The YHDC SCT019 is a high-precision split core current transformer designed for accurate measurement of AC current. Its split core design allows for non-intrusive installation around existing conductors without the need to disconnect the circuit. This manual provides essential information for the safe and effective installation, operation, and maintenance of your SCT019 current transformer.

Figure 1: YHDC SCT019 Split Core Current Transformer, showing its compact design and output wires.

2. Safety Information

Please read and understand all safety instructions before installing or operating the SCT019 current transformer. Failure to follow these instructions may result in electric shock, fire, or damage to the device.

• Qualified Personnel: Installation and maintenance should only be performed by qualified electrical personnel.
• Voltage Rating: Do not exceed the rated voltage of 720V. Ensure the circuit voltage is within safe limits.
• Insulation: Ensure proper insulation of all connections to prevent electrical hazards.
• Circuit Disconnection: Always disconnect power to the circuit before installing or removing the current transformer.
• Environmental Conditions: Do not expose the device to excessive moisture, extreme temperatures outside its operating range, or corrosive environments.

3. Product Characteristics, Applications, and Advantages

Figure 2: Overview of SCT019 characteristics, applications, advantages, and installation diagram.

3.1 Characteristics

• Safety lock clasp for secure installation.
• Easy to install split core design.
• Leading wire output (0.5mm² Black and white twisted pair).
• Can be customized for a variety of output requirements.
• Suspended type mounting.

3.2 Product Applications

The SCT019 current transformer is suitable for various applications requiring accurate current measurement:

• Portable instrumentation.
• Household energy metering.
• Motor load monitoring.

3.3 Product Advantages

• Small volume and light weight for easy integration.
• Low cost solution for current measurement.
• High turns ratio for precision.

4. Installation Instructions

The SCT019 features a split core design for straightforward installation. Refer to Figure 2 for visual guidance.

4.1 Mounting the Transformer

1. Open Upward: Gently pull the two halves of the transformer apart to open the core. The clasp mechanism will release.
2. Position on Lead Wire: Place the open transformer around the conductor (lead wire) whose current you wish to measure. Ensure the conductor passes through the center of the transformer's aperture.
3. Fasten: Close the two halves of the transformer firmly until the safety lock clasp engages, securing the core around the conductor. Ensure there is no gap between the core halves.

4.2 Wiring

The SCT019 provides a voltage output proportional to the measured current. Connect the output wires to your measurement device (e.g., data logger, energy meter) according to the schematic diagram shown in Figure 3.

Figure 3: SCT019 outline dimensions and schematic diagram for voltage output type with built-in sampling resistor.

• The output is a 0.333V AC signal at the rated current.
• The white wire typically corresponds to the 'K' terminal (positive output) and the black wire to the 'L' terminal (negative output) in the schematic.
• For voltage output types, the secondary is not allowed to be short-circuited.

5. Operation

Once installed and wired correctly, the SCT019 will provide a voltage output proportional to the AC current flowing through the primary conductor. This voltage can be read by a suitable analog-to-digital converter (ADC) or a measurement device.

• For the 100A/0.333V model, an input current of 100A will produce an output voltage of 0.333V.
• The output voltage scales linearly with the input current. For example, 50A input will yield 0.1665V output.
• Ensure your measurement device has an appropriate input impedance (typically ≥10KΩ) to avoid loading the transformer and affecting accuracy.

6. Technical Specifications

Figure 4: Detailed technical index and electrical parameters for the SCT019 series.

6.1 General Technical Index

• Material of Core: Permalloy
• Flame Resistance: UL94-V0
• Working Voltage: 720V
• Working Temperature: -25 ℃ ~ +70 ℃
• Storage Temperature: -40 ℃ ~ +85 ℃
• Frequency Range: 20 Hz ~ 1 KHz
• Dielectric Strength: 3.5KV 50Hz 1min
• Weight: 91g

6.2 Electrical Parameters (SCT019 100A/0.333V)

7. Dimensions

The physical dimensions of the SCT019 are crucial for integration into your system. Refer to Figure 3 for detailed outline sizes.

• Product Dimensions: Approximately 50.8mm (length) x 15.5mm (width) x 53.3mm (height) (2 x 0.61 x 2.11 inches).
• Core Opening: The internal aperture for the conductor is approximately 19.1mm x 19.1mm.
• Core Opening and Closing Way: Pull plug type.

8. Troubleshooting

If you encounter issues with your SCT019 current transformer, consider the following:

• No Output Reading:
  • Verify that the primary conductor is carrying AC current.
  • Ensure the transformer core is fully closed and latched around the conductor.
  • Check wiring connections to the measurement device for continuity and correct polarity.
  • Confirm the measurement device is correctly configured to read AC voltage.
• Incorrect Output Reading:
  • Ensure the primary current is within the rated range of the CT (e.g., 0-100A for the 100A model).
  • Verify the load impedance of your measurement device is ≥10KΩ. Lower impedance can cause inaccurate readings.
  • Check for external magnetic fields that might interfere with the CT's operation.
  • Confirm the frequency of the measured current is within the CT's specified range (20 Hz ~ 1 KHz).

9. Maintenance

The YHDC SCT019 current transformer is designed for long-term, maintenance-free operation. However, periodic inspection is recommended:

• Cleaning: Keep the exterior of the transformer clean and free from dust and debris. Use a dry, soft cloth for cleaning. Do not use abrasive cleaners or solvents.
• Connection Check: Periodically inspect the output wiring for any signs of damage, corrosion, or loose connections.
• Physical Inspection: Check the transformer casing for any physical damage, cracks, or signs of overheating. Ensure the core clasp mechanism operates smoothly and securely.

10. Warranty and Support

For warranty information, technical support, or service inquiries regarding your YHDC SCT019 Split Core Current Transformer, please contact your point of purchase or the manufacturer directly. Retain your purchase receipt as proof of purchase for warranty claims.

Manufacturer: Dechang Electronic Co., Ltd