IMC C SERIES User Manual page 81

The IRIG-B module comprises a realtime clock (RTC) with a backup battery, which is set to time and date
according to the IRIG B-signal received. If the IRIG B year codes received equal "00" (depending on used
sub-standard) these are ignored and only RTC time and day values are set, while the year continues to
reflect the value resulting from counting since the last update with a valid year number. This means that
the year number is incremented at the turn of the new year.
To monitor an imc measurement system's synchronization status, it is possible to use the imc Online
FAMOS function "IsSynchronized()". Its return value is "1" if the device is synchronized to an external
time reference; otherwise, a "0" is returned.
Loss of the external time signal is detected within 1 – 2 seconds. However, the process of restoring
synchronization can last approx. 20 – 25 seconds.
Technical Specs of IRIG-B
The IRIG-B module weighs about 55 g.
Optionally, the module can be factory installed in a measurement system.
5.2.6 GPS
At the nine-pin GPS socket it is possible to connect a GPS-receiver of the type Garmin GPS18LVC, GPS18-
5Hz etc.. This makes it possible to achieve absolute synchronization to GPS time. If the GPS-mouse has
reception, the measurement system synchronizes itself automatically. Synchronization with a NMEA
source is possible. The precondition for this is that the clock must return the GPRMC-string along with
the one-second-interval clock signal.
All GPS information can be evaluated and subjected to subsequent processing by imc Online FAMOS.
GPS signals are available as: process vector variables and fieldbus channels (from version imc DEVICES
2.8 / imc STUDIO 4.0).
GPS information
pv.GPS.course
pv.GPS.course_variation
© 2018 imc Test & Measurement GmbH
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Description
Course in °
Magnetic declination in °
Miscellaneous
imc C-SERIES - Manual, Version 4 R 3 - 2018-10-19
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