Clamp meters are more versatile and flexible as diagnostic tools for electricians – while providing less resolution in its measurement than multimeters.
Essential check list for buying a clamp meter
Minimum and maximum current levels
Safety Installation Category Rating for your application
Resolution and accuracy to accurately measure the minimum level of current
Jaw size for access and maximum conductor size
AC only current or AC and DC Current
Ease of use, including features such as auto ranging, backlight and thumbwheel for function selection
Any additional functionality including AC/DC Voltage, Resistance and Min/Max recording
Tips for measuring current
For all general purpose applications excluding leakage current, clamp around a single current carrying conductor. This may mean splitting out the conductor for the rest of the cable.
For low currents: multiplying the number of turns of the current carrying cable within the jaw will multiply the reading by the number of turns.
Always try and keep the conductor in a central position in the jaw for the most accurate readings.
Watch out for current carrying conductors outside the clamp meter jaw, but next to it. The magnetic field from current flowing in the external conductor can cause reading errors.
Always make sure your clamp has the right safety category for the area of the installation you are working in.
Use a True RMS current clamp meter to ensure accurate and repeatable measurements, particularly when troubleshooting overloads.