If the current flowing in an operating circuit must be approximately measured without interrupting the current, which type of current transformer would you recommend?

In a scenario where it is essential to measure the current flowing in a circuit without interrupting the current itself, a split core current transformer is an excellent choice. Split core transformers are designed with a hinged design allowing the core to be opened and closed around a conductor. This feature enables technicians to easily install the transformer around an existing conductor without needing to disconnect it, which is crucial for maintenance or monitoring situations in live circuits.

Using a split core current transformer facilitates safe, non-intrusive measurements. This device can accurately measure alternating current (AC) levels, providing a practical solution for ongoing monitoring in energized circuits. The openness and flexibility of a split core design confer both ease of use and safety, making it ideal for scenarios where electrical isolation and convenience are priorities.

Other options, such as current shunts, also provide measurement capabilities but typically require a direct connection to the circuit, which would necessitate interrupting the current flow. Ring core and Rogowski coils provide different methodologies for current sensing; however, the ring core may not offer the ease of installation seen with split cores, and Rogowski coils, while effective for varying frequency runs, may not be as straightforward in permanent installations in all scenarios. Thus, the split core current transformer stands out as the