Comtech EF Data CRS-150, Инструкция по установке и эксплуатации

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CRS-150 1:1 Redundancy Switch Revision 2
Introduction MN/CRS150.IOM
1–3
As a companion product for the CDM-600, the CRS-150 provides full protection for all Open
Network overhead signals (IDR Backward Alarms, Overhead Data Channels, Audio, etc.), as
well as external reference signals.
An advantage of the CRS-150 redundancy system is the Auxiliary Serial connection
between the modem pair. With the appropriate cables connecting the modems to the
CRS-150, the online unit interrogates the standby unit, at regular intervals, to determine
its configuration. If a difference in configuration is detected, the online unit automatically
reconfigures the standby unit so that the configurations are always synchronized. If the
standby unit is replaced, it does not have to be reprogrammed to match the online unit; the
process is entirely automatic.
Operators can manually force a switchover from the front panel of the online modem,
or via the remote control bus. Alternatively, operators may choose the conditions that
will cause an automatic switchover. Automatic switchover conditions are controlled by
two switches located on the front panel of the unit – this provides a great deal of
flexibility in switch operation. Switch Mode choices are: Unit Faults only; Unit +
Transmit Traffic Faults; Unit + Receive Traffic Faults; or Unit + Tr Receive
Faults.
For operation at the maximum data rate of 20 Mbps, the CDM-600 uses a
serial LVDS interface. However, many applications, including high-speed
routers, use the popular HSSI interface (using negative ECL levels). For
these applications, the Comtech EF Data CIC-20 LVDS to HSSI Interface
Converter module is available.
Also available, for conversion of LVDS to ASI, is the Comtech EF Data
CIC-35 LVDS to ASI Interface Converter module.
Either module typically connects directly to the rear of a standalone
CDM-600. For CDM-600s used in redundancy with a CRS-150, however,
either module plugs into the Overhead / Data Interface connector set on the
front panel of the CRS-150.
Like the CRS-150, the CIC-20 and CIC-35 take their operating power
directly from the modem. However, the CDM-600 modem can safely
supply enough current for only one attached device, not two. Therefore,
when connecting a CIC-20 or CIC-35 to the CRS-150, also connect an
external supply (or supplies) to the CRS-150. This low-current DC supply,
located on the front panel, provides DC voltage between 11 and 15 volts.
While a single supply may be used, for maximum reliability a second
diode-shared input is provided and use of both ‘A’ and ‘B’ supplies is
recommended.
The CIC-20 or CIC-35 module, when either is used, plugs directly into the
CRS-150 front panel – do NOT use a cable for either module.