Arbiter Systems 931A, Руководство по эксплуатации

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3.3.1.16 Last Setup
LAST SETUP
STORE SETUP
Press the LAST SETUP key to restore the instrument-state to
what it was immediately prior to the last change. It may be
used to undo an unwanted change, or to toggle between two
different setups. When LAST SETUP is pressed, the current
state is also stored as the new LAST SETUP.
3.3.1.17 Ch1/Ch2
CH1 / CH2
SCALE
Press the CH1/CH2 key to display the magnitude and phase
of the signal at Channel 1 divided by the signal at Channel 2.
Depending on the input signals selected, the displayed units for
magnitude will be either
ohms (Channel 1 voltage and Channel
2 current), mhos (Channel 1 current and Channel 2 voltage), or P/U (both
channels the same). The value shown for phase represents the phase angle
between the signal at Channel 1 and the signal at Channel 2. It is displayed
in accordance with the phase convention defined for the instrument (see
Section 3.6.1.3).
When using the CH1/CH2 function, any scaling factors for magnitude
and/or phase will apply to the displayed result (see Section 3.3.2.17 for a
discussion of scaling factors).
CH1/CH2 is useful for checking the amplitude and phase angle ac-
curacy of current transformers. Connect the primary in series with a
Model 931A current input and set that input to Channel 1. Connect
the transformer secondary to another current input and set that input to
Channel 2. Set the scale factor for the CT input (see Section 3.3.2.17) and
press CH1/CH2. Using an external source, supply the appropriate level
current.
3.3.2 Secondary Functions
The secondary functions of the front panel keys are shown below. They
are identified by the text located directly above each of the keys, and are
highlighted in gray. Access these functions by pressing SHIFT prior to
pressing the desired key.
3.3.2.1 Shift
Press the SHIFT key to access the functions in the shaded gray areas above
the keys. An indicator in the display shows when the SHIFT key has been
pressed. Press SHIFT a second time to prevent access to the secondary
functions.
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