What are the installation steps for a current transformer?
Nov 24, 2025| 1. Pre-installation preparation: Check the transformer's appearance for damage and confirm that the transformation ratio (e.g., 250:5) matches the meter.
Prepare tools: screwdriver, wire cutters, insulating tape, etc.
2. Installation location: Fix the transformer to the distribution box panel, ensuring vertical installation with an inclination ≤1°.
For through-type current transformers, the transformer should be fitted in the center of the conductor, with P1 facing the power supply side.
3. Primary side wiring: Pass the conductor through P1 and out through P2, ensuring the current direction is correct.
For three-phase meters, connect the transformer to the large holes for the yellow, green, and red phases.
4. Secondary side wiring: Connect S1 to the meter's current terminals (e.g., 11, 12, 13), and connect S2 in parallel to ground.
Use copper wire of 2.5mm² or larger to avoid open circuits.
5. Inspection and Testing
Use a phase meter to verify the polarity, ensuring the phase difference between S1-S2 and P1-P2 is close to 0°.
After powering on, observe the meter reading and multiply it by the turns ratio (e.g., 50 times) to verify accuracy.
Precautions:
The secondary side must be grounded to prevent high-voltage hazards.
Avoid strong electromagnetic interference; maintain a distance of >5m from the transformer.
