Associated Research OMNIA II 8204, Operation And Service Manual

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channel to another channel or from any channel to a common Low or Return
point. The channels can be connected in parallel if desired but there is only one
leakage current measurement for all channels.
The Ground Bond/Continuity channels can only be used to test from one channel
to the common Return. Only one channel may be used for each Ground Bond or
Continuity test. The Ground Bond or Continuity test will be performed between
the output channel selected and the Ground Bond/Continuity common terminal.
Although the G-COM terminal is isolated from the Return terminal during a Hipot
or IR test, the Ground Bond/Continuity channels can be referenced directly to the
Return lead without using the G-COM terminal during a Ground Bond or
Continuity test.
True 4-wire measurement through the Scanner is not possible because of the
Kelvin lead termination, but the Milliohm-Offset feature should be used to reduce
measurement errors. The Return lead Kelvin connection is terminated at the
alligator clip of the test lead, but the G-COM terminal has an internal Kelvin
connection that shorts out the test lead Kelvin connection. Therefore, the
resistance of the Return test lead will be measured during the test unless the
Milliohm-Offset feature is used.
The Scanner will provide output to multiple test points and will have the same
operation specifications that apply to the standard instrument with the exception
of one Ground Bond/Continuity channel limitation: due to the characteristics of
general-purpose High Current relays, some additional contact resistance cannot
be prevented. Although this contact resistance can be offset using the Milliohm-
Offset feature of the instrument, there will be some variation in the contact
resistance because the relay must open and close. Each relay closure may
represent a different resistance value. The Ground Bond channels will have the
following characteristics:
GROUND BOND/CONTINUITY CHANNEL
RESISTANCE DEVIATION
Deviation (Relay Contact) Test Current
6m

maximum

10A
03 Dual Remote Test Switches
The Dual Remote Test Switch option allows the user to configure dual palm
switches for safe production line operation.
To activate the option, you must access the Setup System Menu from the Main
Menu screen. This process is described in section
4.2. Setup System Menu in
this manual. Once at the Setup System screen press the “Hardware” soft key.