Microtest 8751, User Manual

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(4) Test Specification
Sets the test specification of the DC insulation and AC tolerance test; the DC insulation specification can
be set between 0.1MΩ~1000MΩ, 0.1uA~1000uA.
※
When the setting is set as 5MΩ or below 5uA, the maximum test voltage is 650V and the AC tolerance
specification can be set between 0.01mA~5mA.
(5) Offset Value
AC tolerance test offset.
(6) All-Ground
Ground pin must be set for this mode to perform insulation test for non-grounded cable to specified
grounded cable; its advantage is that the test speed is fast, but its disadvantage is that insulation test is not
performed between non-grounded cables.
All ground test method
(7) Binary
This mode is similar to quick categorization; if there are 8 test pins test DUT A B C D E F G H, when test
is performed for each cable or pin, it has to be tested 7 times sequentially in order to determine whether
the test DUT passed. But if the quick test method is used, the first time A B C D and E F G H are divided
into two groups for testing, and the second time A B E F and C D G H are divided into two groups for
testing, and the third time A C E G and B D F H are divided into two groups for testing, then the test only
needs to be performed three times to confirm whether the test DUT passed. Therefore, if the test DUT has
128 pins, and if test is performed for every cable or pin, the test has to be performed 127 times; with the
quick test method, the test only has to run 8 times. However, the disadvantage is that it cannot find out
which are the error pins and the cable segment resistance will be slightly lower than the actual value
because of the cable segments were tested in parallel.
(7-1) Binary Range (Open 1)
This mode is similar to the quick binary categorization method; it allows setting of the test DUT quantity
and range (same as multiple DUT simultaneous test setting).
Quick binary test method
(8) All Nets
This is the most fundamental test method for high voltage insulation test. High voltage is connected to
the test pin A and the other pins are grounded to observe its current leakage or insulation value, and
then high voltage is connected to test pin B and the other pins are grounded to observe its current