7 Important Factors to Consider When Calibrating a Clamp Meter
1. Clamp meters come in a wide variety of shapes and sizes.
The design of the jaw size makes the calibration process difficult, and it is necessary to select the corresponding calibration equipment.
2. Most clamp meters today are multi-function.
In addition to current, most clamp meters can generally measure voltage, continuity, and other functions common to digital,
3. Not all calibrators are up to the job.
At higher outputs, many calibrators are limited to high continuous output currents. Also, you must use a calibrator with sufficient accuracy and compliance voltage sufficient to drive the coil. Fluke uses "L-COMP" (Inductive Compensation) technology to increase the compliance voltage to drive the load.
Coil inductance can cause malfunctions, so avoid current sources not designed for current coils. Transients that turn the current on and off can trip the current source.
4. Current coil winding (number of turns) and measuring range are very important.
The number of turns of the coil used must be sufficient to test the full current range of the current clamp. The coil winding determines the amount of current. For example, a calibrator with 50 turns outputting 20 A will show up to 1,000 A on the clamp meter.
5. Don't ignore attachments.
Some clamp meters may come with a flexible current probe, such as the Fluke iFlex, which must be calibrated with the clamp meter.
6. High current will generate heat.
The current coil must be designed to dissipate as much heat as possible. Coils usually have a maximum operating time specification at a higher current.
7. Positioning is very important.
When aligning the clamp meter with the current coil, be aware of current clamp stray field and position sensitivity. Avoid interference fields from other devices and current conductors. Note the clamp meter alignment marks. Align the axis of the clamp meter parallel to the coil axis and the jaw plane perpendicular to the coil wires.
