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5.2 Overview of Command Keys
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geographical position for the 1133A. After the 1133A has initially found its position, a subsequent
startup may produce a LOCKED indication after tracking only one or two satellites.
Other
indications are “VCO LOCK ERROR” and “UNLOCK XX MIN,” where “XX” can be from 0
to 99 minutes.
Figure 5.4: GNSS Locked Screen
5.1.3
Annunciator LED Startup Indications
Initially, the annunciator LED’s should all flash, and then the Operate and Unlocked LED should
be ON; the Timeset and Fault LED’s should be OFF. After about 30 minutes of internal clock
stabilization, the Unlocked LED should go OFF, and about five minutes later the Timeset LED
should go ON. The Timeset LED serves to indicate that the internal clock is locked to the GNSS
and the time is accurate to within the guaranteed specification (see Chapter 12).
5.1.4
Viewing Electrical Parameters
Pressing specific command keys reveals those specific averaged – once per second – electrical
parameters. Details of these parameters and what you should see are explained in the next section,
Overview of Command Keys.
5.2
Overview of Command Keys
Seven of the front-panel command keys enable you to view specific measured electrical parameters,
and one key – the status key – provides details of the 1133A operational status. Command keys
are
not
used to configure the Model 1133A.
5.2.1
Voltage/Current Key
Press the VOLTAGE/CURRENT key successively to view magnitude and phase angle for each
measured line voltage and current. Phase voltages and currents are listed as “A”, “B”, “C”, “0”,
“1” and “2.” “A”, “B”, and “C” label each of the voltage and current phases, and “0”, “1” and
“2” are labels for each of the sequence voltages and currents. The first illustration below shows
the “A” phase voltage and current, magnitude and phase angle. The second shows the 0 Sequence
values.
Figure 5.5: Voltage/Current Display