95x Series Operating Manual - May 17, 2022
Page
50
of
155
CONNECTING TO THE DUT
for general wiring and safety recommendations.
The 95x requires that the DUT (at least that portion which is being measured) is isolated from ground unless
–
•
Option HSS is fitted
•
And, the SOURCE setting is set to INT (or AC-30 is not fitted)
•
And, the DUT GROUNDED setting is set to YES.
TESTING A DUT WITHOUT OPTION HSS OR WITH DUT GROUNDED SET TO NO
The DUT should be wired between the
HV
and
RETURN
terminals of the 95x; if Opt. AC-30 is being used (SOURCE
setting is set to EXT) then the DUT should be wired between the output of the external AC-30 unit and the
RETURN
terminal of the 95x.
The 95x provides a safety ground for the DUT during the test via its
RETURN
terminal. The Continuity Sense feature
may be used to ensure that the
RETURN
connection is correctly made by connecting the
SENSE+
terminal to a
point on the DUT which is connected to the
RETURN
connection. When deciding which point on the DUT to
connect to the
HV
terminal and which point to connect to the
RETURN
terminal, the user should consider that only
the voltage on the
RETURN
terminal is safe at all times.
For best high impedance load performance there should be low capacitance and leakage between the wires and
for low level current measurements there should be little interference pickup in the
RETURN
wire. In extreme
circumstances the
RETURN
wire should be the inner wire of a coaxial cable, with the shield connected to the
GUARD
terminal of the 95x. This will significantly reduce the capacitance and leakage between the
HV
and
RETURN
wires. A cable such as RG174 is a suitable choice. If the Continuity Sense feature is being used, then the
SENSE+
connection should similarly be a coaxial cable.
The example above shows the connections for performing AC voltage withstand testing of Line/Neutral
connections to the chassis of a DUT. The optional wire from the DUT chassis to the
SENSE+
terminal of the 95x is
used when the user wishes to use the Continuity Sense safety feature.
HV
RETURN
SENSE+
95x
DUT
High Voltage Wire
Optional Wire for
Continuity Sense
Return Wire
L
N
