Calibrating a Clamp on Meter – HOW TOs SERIES

A Clamp On meter (also referred to as a Current Clamp), is an electrical device which allows the measurement of currents flowing through a conductor by means of a Jaw or probe clamped around the conductor.

Clamp On meters are often used for measuring alternating current (AC) and for the measurement of direct current (DC). With a Clamp On meter, there is no need to disconnect a conductor in a circuit or for direct physical contact with the conductors making measurement taking safer and easier.

When to Calibrate a Clamp on Meter

Annual Calibration is typically required for Clamp On meters to ensure measurements are accurate and in line with the original equipment manufacturers (OEMs) specifications.

The frequency of usage of the clamp meter also determines how often it should be calibrated. Whenever a user of the clamp meter suspects that measurement results may have been comprised, then it is imperative for the instrument to be calibrated.

Clamp on Meter Calibration Methodology and Process

When calibrating a Clamp On meter, the following guidelines are very important:

1. Choose your Calibrators Correctly: Special attention must be paid to picking out the correct calibrator(s) for the job. Clamp meters come in all shapes, ratings and sizes.

It is important to pick calibrator(s) that will accommodate the performance ratings of the Clamp On meters as well the physical structure of the jaws or flex probes.

Examples of such calibrators are:

• Fluke 5522A Multi Product Calibrator

• Fluke 5500A 50 Turn Coil

• Calmet C300B Three Phase Calibrator etc.

2. Inspect for physical damage: It is safe practice to inspect all Clamp On meters for any physical damage to the instrument, especially the jaws or probes before proceeding to calibration to protect against injury or damage to lives and properties.

3. Make use of all required accessories: Some Clamp On meters use accessories such as a flex probe for their operations. All these must be used in the course of calibration to ensure compliance.

4. Ensure safe working environment and time: Current coils often generate heat when in operation and typically possess maximum operating time at higher current levels.

Therefore, it is advised to ensure use of current coils designed to dissipate heat quickly, work in a cool environment and suspend tests reaching duration beyond operating limits.