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Bulk HV Isolation Test
Bulk HV Isolation Test with Search
The Bulk HV Isolation custom instruction allows you to perform a high voltage isolation test on a specified
test point. The high voltage test consists of two parts – a Dielectric Withstand Test (DW Test) and an
Insulation Resistance Test (IR test). The DW test is performed first. In this test the tester applies the
selected DW Voltage (from 10 volts to the highest capability of the tester) and monitors current flow. Any
spike in current flow above the DW Total or Real Current settings causes the DW test to fail. During the
IR test, the tester attempts to raise the source point to the selected IR Voltage, which must be equal to or
less than the DW Voltage setting. Current flow into the source test point is measured as it relates to
isolation resistance (IR). If the measured resistance is lower than the minimum IR resistance setting, the
test fails. During both the DW and IR tests the tester sinks to ground or floats other test points depending
on the Bulk Isolation Mode Setting described below.
The high voltage parameters for this custom instruction are identical to those set for the CH2 standard
high voltage settings. For more information on these tests and their parameters see Insulation
Resistance Test (IR Test) and Dielectric Withstand Test (DW Test) in the help system.
Note that Try It will not be active until after the HV Parameters window has been accessed at least one
time. Clicking on Try it will immediately perform the DW and IR tests and return the IR resistance if the
high voltage tests passes.
with Search
If you want the tester to locate the “failed to” test point, use the HV Bulk Isolation with Search custom
instruction. To test at higher isolation voltages under 10 volts see the custom instructions, LV Bulk
Isolation Test and LV Bulk Isolation Test with Search.
Bulk Isolation Mode
The Bulk Isolation Mode can be set as follows:
All
The isolation of the specified test point will be tested relative to all other test points in the test system.
Note that if All is selected, the test point must not be connected to any other test point (not be part of a
net), otherwise the custom instruction will fail. Therefore use of All should be limited to verifying that
individual “non connected” test points are truly isolated.
Lower
The isolation of the specified test point will be tested relative to all test points with lower system point
numbers in the CH2 test system. For example if this custom instruction were used for test point 147, test
point 147 would be tested relative to the test point 146, 145, 144, all the way down to test point 1. Note if
using Lower to check for the isolation of a net, it is important to specify the lowest system point of the net.
Otherwise this custom instruction will fail when other system points are found connected to the specified
test point.
Upper
The isolation of the specified test point will be tested relative to all test points with higher system point
numbers in the CH2 test system. If using Higher to check for the isolation of a net, it is important to
specify the highest system point of the net. Otherwise this custom instruction will fail when other system
points are found connected to the specified test point.
None
The isolation of the specified test point will be tested only relative to earth ground.
All but net
If other custom instructions indicated that the specified point is part of a net, the specified test point is
tested relative to all other system points outside the net. If the specified custom instruction is not part of a
net, the tester will test it relative to all other test points in the test system.
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