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high voltage is remote controlled, so the operator can not know the actual working state of the
tester through the interface.
Please pay special attention to the reliability of remote control
connection:
[STOP]
key must be connected reliably, and the
[STOP]
key must be pressed before
changing the DUT.
When working in a crowded work environment, the remote control switch must have an
interlock
[INTLOCK]
and the high voltage indicator. Disconnect the interlocker
[INTLOCK]
before changing the DUT.
When testing voltage output, the operator or any other person is prohibited from touching the
DUT, test lines, probes, output terminals and areas around them.
6)
Test Completion Confirmation
If you have to touch the high voltage area such as the DUT, test leads, probe or output terminal
because of reconnection or other test-related conditions, please confirm:
The power switch is turned off or the working status of the tester is not in the test state,
and DANGER lamp has gone out.
The DUT may be charged with high voltage even after test completion, so please pay
special attention whether or not the DUT is fully discharged.
7)
High Voltage Testing Discharge
In high voltage testing, test lead wires, probes and DUT are all charged with high voltage. The
tester is equipped with a discharge circuit, but it still requires some time to discharge after the
output is cut off. There is a danger of electric shock during discharge, do not touch anything that
could cause an electric shock. As soon as the output is cut off, the tester’s discharge circuit
starts forced discharging. Do not disconnect the DUT during a test or prior to the completion of
discharging.
Discharge time:
The time at which the voltage is completely discharged is determined by the test voltage used
and the characteristics of the DUT.
During the test process, discharge of the DUT is conducted by the transformer secondary
winding (approximately resistance of 2k) and approximately 0.1s is required for a 10µF
capacitor with high voltage of 6000V to discharge to 30V. The fixed discharge time of the tester
is 0.2s, which ensures complete discharge of the tester. The internal filter capacitor of the tester
is discharged through the discharge circuit, which ensures complete discharge of the tester
within 0.2s.
Assume that a high voltage is applied to a DUT, equivalently, a high voltage is applied to a
circuit with a 0.01µF capacitor in parallel with a 100MΩ resistor, if the DUT is disconnected
during a test or prior to the completion of discharging, approximately 5S is required for DUT
with high voltage of 5000V to be discharged to 30V, approximately 3.5S is required for DUT
with high voltage of 1000V.
Computational formula of discharge time: t = -In (30 / U) ×R×C
t: discharge time
30: discharge residual safety voltage 30V
U: test set voltage
R: discharge impedance of the DUT, approx. 2KΩ
C: capacitance of the DUT
