DOC 6511_Release K
ATS-6511A/B/C Users Guide
16
The
mode
indicates the ATS-6511 is using the manual feature. In this case the Input A indicator
will be On and Green to indicate the system is locked to the primary (master) source. The Input
B indicator will flash RED (on 1 second/off three seconds) to indicate the source is available and
the system is in the manual switching mode.
If there is a loss of signal on Fiber A the Input A indicator will turn RED to indicate there is an
issue with that source however the system will not automatically switch over to Input B. The
Alarm Indicator will turn RED and the Oscillator Lock Indicator will go out indicating the system
is free running on the internal clock. Once Input A is restored the Input A indicator will flash
RED (on 1 second/off three seconds) to indicate the source is available. Once the ATS-6511
locks to the reference signal on Fiber A input the Input A indicator and the Oscillator Lock
Indicator will turn Green and the Alarm Indicator will go out.
The indications for Input B will not change unless the ATS-6511 is commanded to use Input B
(
fiber_switching manual B
) or the input signal to Fiber B is Lost. Once this occurs the Input B
indicator will turn Green and the Oscillator Lock Indicator should come on within a few seconds.
After this the Alarm indicator should go out. The system will remain on Input B until
commanded otherwise. Once the signals are restored The Input A indicator will flash RED (on 1
second/off three seconds) to indicate the source is available and the system is in the manual
switching mode. The Fiber B indicator will turn RED and remain on if the input signal is lost.
2.6
Fiber Modes/Calibration
The ATS-6501/6511 systems are capable of operating in three distinct modes. This section
assumes the on-time-point (OTP) of the system is the rear panel outputs on the ATS-6511. This
may not be the desired location for the OTP; users should refer to section 2.7 for information on
changing the location of the OTP for the system.
Warning:
Users are cautioned to set the system (ATS-6501, TSC 4340A, and ATS 6511A/B/C)
up in the desired operational configuration and calibrate any ATS-6511s in the two_way_disabled
fiber mode to ensure the 1PPS outputs are either known or compensated for as described below.
Changes to the system configuration will likely require re-calibration. If you have questions
contact Symmetricom.
2.6.1 Two Way Mode (ATS-6501 with 4372A-T Fiber Card)
This mode uses the data exchange between the ATS-6501 4372A-T (Two-Way fiber card) and
the fiber A/B input on the ATS-6511 to calibrate the output of the ATS-6511 and set the system
on-time point (OTP) to the rear panel of the ATS-6511. The fiber path may pass through a TSC-
4340A. This method provides three distinct advantages. 1) The delays between the 6501 and
6511 are constantly measured and the system will compensate for any changes (i.e. diurnal
changes with or without a 4340A). 2) The pair of fibers for Input A and Input B do not have to be
the same length and could take separate paths. 3) The system calibration is automatically done
for each pair of fiber inputs as long as the fibers for that pair are of equal length. If the individual
fibers used in the pair paths to Input A or B are different length, the path length difference
between the two fibers must be determined and the fiber delay difference programmed in for each
input (A and/or B).
Summary of Contents for ATS-6511A
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