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Measurement principle – KYORITSU 5410 User Manual

Page 12

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6. Measurement principle

This instrument has a constant current circuit, and drives leakage
currents (I) between LINE-NEUTRAL as illustrated in Fig.5 to activate
RCDs, moreover, can output and measure leakage currents flowing to
the earth as shown in Fig.6.

Trip time measurement:

Measure and display the time between the start of driving leakage

currents (I) and trip of the RCD.

Trip out current measurement:

Increase the leakage current gradually from the 40% of IΔn,

the current value when RCD trips is displayed.


Influence of the fluctuations in system voltages is less on this instrument
due to the incorporated constant current circuit.














Fig.5

Fig.6

Leakage
current

Power

Load

LINE

NEUTRAL

KEW 5410
Constant
current
circuit

EARTH

KEW 5410
Constant
current
circuit

Leakage
current

Load

Power

LINE

NEUTRAL

10