Fluke 5790A, Руководство оператора

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Front Panel Operation
Introduction
4
4-3
4-1. Introduction
This section presents instructions for operating the 5790A from the front panel. Controls, displays,
and terminals are identified and described in detail in Section 3. The first part of this section is
general and applies to all modes of operation.
Operating instructions are presented separately for measurement mode and transfer mode. Refer to
the instructions for measurement mode if you want to measure ac voltage as you would with an ac
voltmeter. Refer to the instructions for transfer mode if you want to apply external standards to the
5790A and use it as a transfer standard.
Different uncertainty specifications apply to measurement mode and transfer mode, as listed in
Section 1. Use the specifications to help determine which mode of operation is best for your
application.
In measurement mode, the 5790A uses its internal dc reference and software control to
automatically make a transfer and show the measured rms voltage of a signal at the input. In
transfer mode, the uncertainty contributed by the 5790A is smaller because the instrument is
simply comparing inputs and presenting the difference between the two. The 5790A is
exceptionally accurate in detecting the difference in levels between rms ac and dc voltages applied
to its inputs.
4-2. Turning on the 5790A

Warning
To avoid electric shock, make sure the 5790A is safely
grounded as described in section 2.
Note
Before turning the 5790A on, make sure that the line voltage selection switches are
set properly for your line voltage. Refer to Figure 2-3 or the line voltage switch
label and verify the line voltage setting now if you have not already done so.
When you turn on the 5790A, it undergoes thorough self testing, and the Control Display shows
the name of the test in progress. If a self test fails, a prompt on the Control Display identifies the
failed test and prevents further operation of the instrument. For information about self diagnostics,
refer to Section 3 of the 5790A Service Manual. The following internal systems are verified at
power up:
•
ROM Checksum
•
RAM Checksum
•
Control Display
•
Measurement Display
•
Guard Crossing DUART
•
Rear-Panel DUART
•
IEEE-488.2 Interface
•
Internal Calendar and Clock
•
Watchdog Timer
4-3. Power-Up State
After passing power-up self tests and any time you press [RESET], the 5790A goes into
the power-up state. The only power-up setting that is nonvolatile (saved when the power
is turned off) is the Initial Input setting. When you turn on the power or press [RESET]