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Io/Ior Leakage Clamp Meter

MCL-400IR Digital Ior Leakage Current Clamp TesterIor AC Leakage Clamp Meter φ40mm

Ior Leakage Current


About Ior Leakage Current
Recently, the leakage current clamp meter is widely used for insulation control of low voltage circuit as the supplementary method of the insulation resistance measurement. The control of leakage current has the advantages to enable the prediction of insulation condition in the electrical power line without having to shut off the power. The leakage current (Io) includes the capacitive leakage current (Ioc)originated in the capacitance and the resistive leakage current (Ior) originated in the insulation resistance each related to the ground. It is considered that the measurement of resistive leakage current (Ior) is the very useful and effective method for the insulation control of low voltage circuit. However, it was difficult to measure the resistive leakage current (Ior)with traditional leakage current clamp meter. MCL-400IR new digital clamp tester enabled the measurements of the resistive leakage current (Ior)without voltage input(phase detection).

0 available in stock as of January 15, 2022

Measuring Principle for Ior Leakage Current It is observed that the load connected to the low voltage side of the transformer generates the harmonics in the current flow in the power line. And it is observed that5th and 7th harmonics current causes the phenomenon of voltage drop at the high voltage side of the transformer.

This voltage drop at high voltage side added the drops of other related power line generates the terminal voltage with harmonics at low voltage side. Thus, 5th and 7th harmonics is generated at the low voltage side by the influence of high voltage side, and it is considered the ratio of 5th and 7th harmonics current is always constant. Consequently, the ratio of 5th and 7th harmonics flowing into earth line is changed proportionally according to the ratio of capacitive component and resistive component in the circuit.

On the other hand, when the long line is used, it is observed that the fundamental current component into earth line is increased proportionally and the ratio of 5th and 7th harmonics is also changed due to the increase of capacitance and inductance of the circuit. By above fact, the calculation factor can be obtained by the measured ratio of 5th and 7th harmonics current and fundamental current component into earth line. Thus,the resistive leakage current Iorcan be obtained by the computation of the culculation factor and compensation factor of the circuit.

And it is reported that the satisfactory test result was observed from our many practical field tests in Japan.
Measuring function Load current, leakage current (Io)
Resistive leakage current (Ior)
Harmonics current and voltage
(Fundamental, 3rd, 5th, 7th, 11th and 13th)
AC Voltage
Measuring method Dual slope integration mode
Display 3.5 digit LCD, max. reading of 4000
Range AC 0-40mA, 400mA, 4A, 40A, 300A,
AC 0~500V
Accuracy Measuring Function/Range/Resolution/Accuracy
AC Current/40mA/0.01mA/±1.0%rdg±8dgt
AC Current/400mA/0.1mA/±1.0%rdg±8dgt
AC Current/4A/0.001A/±1.0%rdg±8dgt
AC Current/40A/0.01A/±1.0%rdg±8dgt
AC Current/300A/0.1A/±1.0%rdg±1%FS
AC Voltage/500V/0.1V/±1.0%rdg±8dgt
Accuracy for Harmonics Current and Voltage Fundamental, 3rd, 5th, 7th : 1%rdg±5dgt±AC current and voltage accuracy
11th and 13th Harmonics : 2%rdg±5dgt±AC current and voltage accuracy
(Min. fundamental input current : more than 2% of each current)
CT opening capability φ40mm
AC Conversion Average sensing rms reading
Input Frequency 45-65Hz
Over range indication "OL" mark on LCD
Low battery indication "Battery mark" on LCD
Auto power off function Approx. 10 minutes later after final key operation
Data hold indication "DH" mark on LCD
Influence of external magnetic field Less than 5mA (nearby 100A conductor)
Sampling 2 times/sec, 1 time/6 sec. for Ior measurement
Limitation of circuit voltage Less than AC 500V
Withstanding Voltage AC 2200V, 1minute
Operating Temperature 0℃~40℃, < 80%RH ( Without condensation )
Storage Temperature 10℃~60℃, < 70%RH ( Without condensation )
Power supply 1.5V ("AAA" sixe, um-4)x3 or AC adaptor (Option)
Power consumption Approx. 8mA (Approx. 60 hours continuous)
Size and Weight 70(W)x223(H)x34(D)mm
Approx. 440g including batteries