Arbiter Systems Portable Power Sentinel 933A, Руководство по эксплуатации

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2.3.6 Synchronizing the 933A
Synchronize the 933A with either an Arbiter GPS Module (AS0077600)
or unmodulated IRIG-B time signal. Either of these two external timing
signals will keep all the 933A measurements synchronized.
When not connected to an external timing signal, the internal clock
runs off of the crystal oscillator and typically has a drift of less than one
second per day. When connected to the GPS, the time base error is less
than 1 microsecond when locked to at least one satellite. When locked to
an IRIG-B signal, the time base error will be less than one microsecond
plus the accuracy of the IRIG-B source.
Using the accessory GPS module (see Section 1.4.13), or an available
unmodulated IRIG-B signal, you can easily connect these signals to the
Model 933A for additional accuracy and synchronized measurements. The
following paragraphs will assist you with setting up and using these
features.
2.3.7 GPS Timing Signals
To use the Global Positioning System (GPS) as the phase reference for
synchronizing the 933A you must have the Arbiter GPS module connected
to the GPS connector located on the 933A front panel. Also, the GPS
module must be locked to the GPS. Since the GPS receiver and antenna
are housed in the same (external) module, it receives power from the 933A
and sends down-converted timing signals through the cable via RS-485.
GPS Setup
1. Mount the GPS module in a stable manner in which the antenna
module has a clear view of the sky in all directions. If this is not
possible, a partial view of the sky may also work.
2. Turn the 933A OFF and connect the cable from the GPS module to
the GPS Receiver connector on the 933A
3. Press the power switch to turn on the 933A.
4. Once connected and operating, the 933A should detect the presence
of the GPS signal as the time reference. If you connect the GPS
signal with the 933A powered on, you will need to select SETUP
>
1-Clock Time Set > ACTIVATE GPS RCVR.
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