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4.4.4
DC charging current detection
This function is used to judge the connection of DUT. DUTs are generally capacitive
components. In DC mode, the distributed capacitor will be charged at the voltage
rise time (when the measurement starts) and its
current will be much larger than the tested current
being set. The charging current will fall quickly
when the capacitor is fully charged. The presence
or the absence of the charging current can judge
the connection of DUT. When using this function,
the test waiting time should be set longer than the
charging time so as to avoid wrong judgment.
4.4.5
High-voltage test
This function is used to make high-voltage test on DUT. The test circuit should be
connected correctly. The measurement result will not be affected by special attach
parameters and be the real withstanding-voltage current required by the test.
4.4.6
Voltage fall
It is the same as the voltage rise function depending on the characteristics of DUT.
The voltage will fall when the high-voltage test ends. The resolution of the output
voltage, controlled by the instrument, varies in every 0.1S and depends on the test
voltage and the voltage rise time {ΔV = V / (10*S)}. If the voltage fall time (FALL
OFF) is turned off, the default voltage rise time will be 0.1S.
4.4.7
Electric wall function
Electric wall is used to check the ground current and avoid shocking in the process
of testing. When outputting high voltage, the current from voltage output terminal
will go back to shell through body with serious consequences.
Instruction:
When starting electric wall, if ground current is larger than 0.5mA, the
instrument judges this as electric shock.
When electric wall is closed (analogy: closed test cage), if ground current
is larger than 30mA, it also judges as electric shock.
When the judgement is shock, the instrument will stop output of high
voltage within 0.3S, and quit test status, as well as display GFI FAIL.
Note 1: When ground current through the operator reaches 30mA, it is so serious
that it will cause coma or death. It is suggested to open electric wall if you don’t
use a test cage with interlock function.
Note 2: Remember this only triggers if there is leakage to ground. It will not protect
you if you are between HV and low terminal, just like an RCD will not help if you
touch two phases or a phase and return as there will be no fault current.
