95x Series Operating Manual - May 17, 2022
Page
16
of
155
When using high voltages, even if there is sufficient insulation, there may be significant capacitive coupling which
can cause an unsafe current to flow to nearby objects and corona can occur even outside of the insulation. This is
made worse by sharp corners on objects or the wiring. In severe cases corona can cause interference with the
measurements of the 95x and will reduce the capabilities of the wiring insulation over time, eventually resulting in
insulation failure.
When using extremely high voltages, especially when using Opt. AC-30, there may be significant mechanical force
between the
HV
wiring and nearby objects. Loose wiring can move several inches, and nearby loose objects (e.g.,
screws or papers) can be attracted to the high voltage wire.
All terminals of the 95x other than the HV terminal are always protected to be within a safe voltage of the 95x
chassis ground, so high voltage wire is generally unnecessary for connections to them.
Should the DUT exhibit significant breakdown or arcing while being tested, there may be very high energy HF
interference generated. Although this only lasts for a small period of time before the 95x shuts down, in severe
cases this can damage nearby equipment, such as computers. The wiring between the 95x terminals and the DUT
should be routed as far as possible away from other equipment and from all cabling connected to other
equipment.
When charging high capacitance loads to high DC voltages the capacitor may be unsafe if it or the wiring to it
exhibits breakdown while being tested. The energy in the breakdown is generated by the capacitor itself, so there
can be no limit on this energy imposed by the 95x.
WARNING -
SOME 95x MODELS PRODUCE CURRENTS OF UP TO 40Arms ON THE AND -
TERMINALS. THE USER MUST ENSURE THAT CONNECTIONS TO THESE TERMINALS HAVE A SUFFICIENT
CURRENT CARRYING RATING.
The current rating of all wiring must be sufficient for at least the highest current expected from that terminal
during the test sequence.
Generally, all wiring should be rated for at least 100mA, but the
and
SOURCE-
terminal wiring for a 952i,
954i, or 959i performing Ground Bond testing should be rated for the highest set test current (this may be up to
40A).
USER ACTIVATED SAFETY ABORT
•
The user may depress the
STOP
button on the 95x front panel at any time while a test sequence is being
run to remove the voltage or current as quickly as possible and abort the test sequence.
•
The user can configure for a digital INTERLOCK signal to be input to the DIO Interface which will abort a
high voltage or current test step if the interlock is opened. See
•
The user can configure for a digital ABORT signal to be input to the DIO Interface which will abort any type
of test step if asserted. See
•
There are several interface commands which can be used to abort a running test sequence. See
AUTOMATIC SAFETY ABORT
•
For AC or DC voltage test steps, if the breakdown current level is set to <7mApk and the HI SAFETY setting
in the CNFG - TEST menu is enabled, the 95x will fail the test if excessive
HV
terminal current is detected.
This effectively reduces the drive capability of the 95x to a safer level of current (nominally 7.5mA peak)
during these test steps. See
