Arbiter Systems 120A, Руководство пользователя

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Pulse Per Day (PPD)
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Pulse Per Hour (PPH)
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Pulse Per Second (PPS)
4.2.4.1 Unmodulated IRIG-B
IRIG-B is a serial time code developed by the US military’s I nter- R ange I nstrumentation G roup for range timing
that has been adopted by many different industries. The IRIG-B timecode has a time frame of 1 second with an
index count of 10 milliseconds and contains Time Of Year (TOY) in days, hours, minutes, seconds, and year
information in a BCD format and seconds-of-day in SBS. The Model 120A supports the unmodulated (DC level
shift) versions of the IRIG-B standard B000 and B003, B004 (RCC 200-16) in both local or UTC time. The control
functions of B000 and B004 follow IEEE C37.118 timing specifications.
4.2.4.2 DCF77
DCF77 is a one-minute time code with an amplitude-modulated, pulse-width coded 1 bit/s data signal. The first 20
bits are special flags. The minutes are encoded in bits 21
– 28, hours use bits 29 – 34, and the date is transmitted
during seconds 36 – 58. In the event of an added leap second, a 0-bit is inserted during the 59th bit.
4.2.4.3 Pulse Per Day (PPD)
Provides a pulse every day at the start of the day with a 10 ms pulse width.
4.2.4.4 Pulse Per Hour (PPH)
Provides a pulse once an hour at the top of the hour. The delay value, from 0 to 10000 ms can be used to offset
from top of the hour.
4.2.4.5 Pulse Per Second (PPS)
The one pulse-per-second output is a pulse transmitted at the start of every second with a 10 ms pulse width. The
rising edge is the on-time mark of the signal.
4.2.5 SPST Relay Contact
A Form A SPST solid state relay provides contact closure for several clock conditions and programmable pulse
modes. The contacts are normally open (NO). “Normally” refers to the relay condition when t he clock is powered
off. Out of Lock and Fault are considered failsafe as when the condition is met the relay is asserted and the
contacts are closed. Power failure will result in open contacts and indicates a fault and out of lock condition.
Available settings are:
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Disabled
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Open
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Closed
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Out of Lock (OOL)
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Fault
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Pulse Per Minute (PPM)
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Pulse Per Hour (PPH)
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Pulse Per Day (PPD)
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Single Trigger (ST)
OOL – Indicates if the GNSS receiver is receiving enough satellites to produce an accurate time. The contacts will
be open when there are not enough satellites and will be closed when satellites are being tracked. The
activation/deactivation can be delayed from 1-99 minutes.
Fault – Indicates if an internal error is affecting proper operation of the Model 120A. The relay contacts will be
open in the presence of a fault and closed under normal operation. Please see section 5.3 for detailed fault
information.
PPM – Provides a 10 ms contact closure once a minute at the top of the minute.
PPH – Provides a 10 ms contact closure once an hour at the top of the hour.
PPD – Provides a 10 ms contact closure once a day at the start of the day.