For information about installing modules for line module redundancy, see Chapter 5, Installing Modules. For information about configuring and managing SRP module redundancy, see E-Series System Basics Configuration Guide, Chapter 5, Managing Line Modules and SRP Modules.
Power
All E-series routers provide a power architecture that distributes redundant –48 VDC feeds through the router to each line module, SRP module, and fan module where DC-to-DC converters provide local conversion to the required secondary voltages.
The ERX-310 router is available with either DC or AC power inputs. The AC-powered version can be configured with one or two hot-swappable power supplies for optional redundancy (see Figure 1-8and Figure 1-9). The power supplies convert AC power to internal –48 V redundant DC feeds that are then distributed through the router.
Fans
Forced air-cooling keeps the temperature of the E-series modules and components within normal operating limits. In ERX-14xx models, six cooling fans are located in a tray at the top of the router (see Figure 1-4). In ERX-7xx models, four cooling fans are located in a tray on one side of the router (see Figure 1-6). In the ERX-310 router, two cooling fans are located in a tray on one side of the router (see Figure 1-8).
The system monitors the temperature of each module. If the temperature of a module exceeds the maximum limit, the system immediately goes into thermal protection mode. In this mode, the modules consume extremely low levels of power. For information about troubleshooting high operating temperatures, see Chapter 10, Troubleshooting.
In ERX-7xx/14xx models, the fan tray has two redundant converters that power the fans (for the ERX-14xx models, a –24 V, 50 W converter; for the ERX-7xx models, a –12 V, 15 W converter). If one converter fails, the other takes over. The ERX-310 router does not have redundant converters.
For all E-series routers, the system software reports an alarm if any of the fans or converters fail.
