Current clamps, also called current probes, current meters, and clamp meters, are two-jawed measuring instruments designed to measure the current flow within wires, busbars, cables, and conductors. These instruments measure both AC and DC by converting them into visual form. The voltmeter, digital multimeters, oscilloscopes, power analyzers, and recorders read the clamp’s output. Furthermore, these “Amp clamps” (known in the United States) can measure the current in a conductor without disconnecting or changing the cable.
Current Probe:
Like current clamps, current probes measure current flow in various cables, wires, and conductors; however, they are jawless. These probes detect the current (AC and DC) passing across a conductor by transforming the current into measurable voltages. Additionally, the current probes are utilized with current testers and oscilloscopes.
Key Factors When Buying a Current Clamp:
It is crucial to consider various parameters before choosing a suitable current clamp for your applications. The initial factor is to ascertain the current type to measure, such as AC or DC. Secondly, the cable type should also be considered, along with the current frequency. Some other essential factors include:
- Resolution
- Accuracy
- Size
- Weight
- Operating conditions (such as vibration, dust, water, and temperature).
Working Principle of Current Clamps:
A current clamp measures AC and DC by clamping around electrical conductors using clamp jaws that open and close. They operate without any physical contact with the current and without breaking electrical circuits. These clamps can also work in conjunction with devices devoid of built-in current probes, such as clamp meters and digital multimeters. Additionally, they can be powered by a battery or connected to power supply systems.
Types of Current Clamps:
These current probes are classified into several types, including:
- Open-loop current clamp probe
- Closed-loop current clamp probe
- Current transformers clamp current probes
- Flexible current probes
- Coreless current clamp probes
Typical Applications of Current Clamps:
Current meters/clamps are indispensable instruments where current flows. They are used to find the correct magnitude and efficiency of current flow along with their monitoring. They are also common in:
- Distribution panel installation
- Industries
- Circuit cabinets
- Induction motors, and
- Electromagnetic compatibility, where they are used to sense the current leakage.
