Meinberg IMS-RSC, Руководство по установке

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4 LEDs, Switches, and Interfaces on the IMS-RSC180
2. Auto/Manual Switch
This switch selects between Automatic and Manual mode. Manual mode overrides the module’s internal selec-
tion logic and the reference clock used for signal generation can only be selected manually using the Clock 1
/ Clock 2 switch. In Manual mode, outputs are always enabled, regardless of the synchronization state of the
clocks.
"Auto" Switch Position
The reference clock is selected by the RSC’s internal control logic. The Master Clock is selected based on the
TIME_SYNC signals generated by the receivers, which indicate the synchronization status of the clocks.
To prevent switchovers from being unnecessarily performed (for example, if one clock regularly falls back to
a free-running oscillator while the other is synchronized), the Master and Backup Clock will be swapped upon
each switchover. This Master/Backup relationship will only be swapped back if the new Master Clock (formerly
the Backup Clock) loses synchronization while the Backup Clock (formerly the Master Clock) is synchronized.
If both clocks are running off their respective oscillators, no switchover will be performed; the current state will
be retained and the outputs are disabled if so configured (using the menu & controls on the device’s display).
Important: To ensure that the automatic switchover mechanism is effective, the remote management functionality
must be disabled via the display panel menu: Ref. Time → Switch Unit → SCU Cntl → MANUAL: disable . If
remote management is left active, the system will use the clock selected by the manual control mechanism and
the unit will not switch over to the current Master Clock.
Manual Mode (Display Panel Menu)
In Manual mode, the reference clock is selected from the display panel menu. In this case, errors will not cause
the reference clock to be switched over, and pulse & frequency outputs as well as the serial interfaces will
remain enabled.
Menu:
Switch Unit → SCU Cntl → MANUAL : enable
Note:
A LANTIME Display Unit (LDU) can optionally be used for systems without a display panel (M1000S and
M3000S).
Menu "Switch Unit → SCU State"
OK
SCU State
-> SCU Cntl <
SCU INFO Mode: manual
CLK1:1 CLK2:1
MUX: enabled
Selected Clk: 2
This menu displays the status information of the RSC:
Mode:
Manual | Automatic
CLK1 / CLK2: Status of reference clocks
MUX: Enabled | Disabled - Status of output signals while clock is running from oscillator
Selected Clk: Selected reference clock (1 or 2)
IMS-RSC180 Date: December 17, 2021 7