Purpose 1: Measure three-phase three-wire circuit current and three-phase four-wire zero line current

A clamp meter usually measures the current of a single wire. If two wires are clamped in simultaneously when measuring the current of a three-phase three-wire load, the indicated current value should be the current of the third wire.

The method of measuring the zero line current of a three-phase four wire circuit is the same as measuring the current of a three-phase three wire circuit. At the same time, clamp in three phase lines, and the indicated current value is the zero line current value.

Usage 2: Clamp meter for measuring small currents

Purpose 3: Determine the name of the current in the circuit

Purpose 4: Measure the no-load current of nameless motors to determine the rated power

Calculation formula: divide no-load current by zero point eight, and calculate power close to grade.

The steps are as follows: Measure the no-load current value I of the motor, and according to the empirical formula: p=I/0.8

Usage 5: Measure the no-load current of a 380V welding machine without a nameplate to determine the apparent power S

Estimation formula: The capacity of a 38th welding machine is equal to the no-load current I multiplied by 5.

The steps are as follows: Measure the no-load current value I of the welding machine, and according to the empirical formula: p=5I