XS series operating manual
XS user manual v0.55
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Breakdown detection mode selection
Fig 8.6
It is possible to select various breakdown detection mode.
Current variation mode :
I
The
TEST detector automatically carries out the subtraction between the current which flows
normally in the device under test (I=U/Z) and the one which occurs at the time of a fault (I'=I+Ifault).
Maximum current limit : IMAX
The unit monitors permanently the current flowing through the sample under test and compares
according the 2 following possibilities:
The high limit ( IMAX) > 0 , the low limit (IMIN) is set to 0
If the measured current is > or = to the IMAX, then the test is FAIL ( breakdown)
The high limit ( IMAX) > 0 , the low limit (IMIN) is set to a value < IMAX
If the measured current is < IMAX and > IMIN then the test is PASS, otherwise the test
is FAIL ( breakdown or I < IMIN)
WARNING :
This detection mode can require between 200 and 300 msec. for the limit detection, and
during this time the current can increase quickly over the limit .
Fast maximum current limit : F(ast)IMAX
Specifications are identical to the IMAX detection mode .
However in the FIMAX mode the breakdown detection is fastest (20 msec.) than in IMAX mode
because the comparison with the current limit is performed directly by electronic circuits and not
by the embedded software. The comparison accuracy is lower than the IMAX mode.
Fast maximum current and variation current limit : FIMAX +
I
This mode combines the FIMAX mode and the Delta I mode.
