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Page Rigel Medical
62353+
user Manual V1.4
Low leakage currents of less than 75µA are difficult to measure using the Differential
Leakage method. As such the Differential Leakage method is unsuitable for measuring
conductive un-earthed parts and in those instances where leakages are expected to be
below 75µA.
Alternative method
; This method is in fact similar to a dielectric test between the
mains parts and all accessible parts (conductive and non-conductive) including the
Applied Parts connected together.
The test is performed using current limited (3.5mA) mains potential sinusoidal 50Hz
signal. (60Hz where this is the mains frequency)
The 1kΩ measuring device (equivalent to that used in the IEC 60601 standard – see
Appendix C) is positioned directly after the voltage source.
Measurements are with the protective earth to the EUT interrupted.
As Live and neutral are shortened, the Device will not be powered and mains reversal is
not applicable.
Due to the Alternative measuring method, the EUT doesn’t require to be positioned
isolated from earth.
The Alternative Method is not suitable for equipment having active circuitry and relies
on incoming mains to be fully exposed to the potential leakage.
The Alternative method is highly repeatable and as such is ideal for trend analysis on
Medical Equipment not including active circuitry.