Johnson Controls Metasys NAE55, Installation Manual, Page: 10 / 20

Note: The 24 VAC power to the network engine
charges the data protection battery. At initial
startup, the battery requires a charging period of at
least two hours before it supports data protection
if power fails. Maximum protection (up to three
consecutive power failures without recharging time)
requires a 24-hour charging period.
Figure 16: Network Engine data protection battery
Table 9: Data protection battery details
Callout Description
1
Data protection battery
2 Battery strap
3 Data protection battery compartment
4 Battery cable connectors
Setting the end-of-line switches
The network devices at each end of an FC Bus segment
must be set as network terminated devices. The network
engine has two EOL switches (one for each FC Bus)
that enable you to set the network engine as a network
terminated device on the bus.
To set a network engine as an FC Bus terminated device,
position the switch on the EOL switch block to the ON
position (Figure 17).
Figure 17: FC Bus EOL switch in the factory default ON
(up) position
Note: The EOL switches on the network engine are
factory set to ON (Figure 17). If the network engine
is not a terminated device on the FC Bus, reposition
the switch on the EOL switch block to the Off (down)
position.
Set the EOL switches appropriately for the FC A and
FC B buses. The network engine follows the same
rules as other switch-terminating devices listed in the
Setting Terminations sections of the N2 Communications
Bus Technical Bulletin (LIT-636018) and the MS/TP
Communications Bus Technical Bulletin (LIT-12011034) .
Powering on the Network Engine
Apply power to the network engine by plugging in the
gray 2-pin terminal connector to the power terminal port
on the network engine (Figure 3). The network engine
requires approximately 3 minutes to start up and become
operational. See the LED test sequence at startup section.
Startup is complete and the network engine is operational
when the (green) RUN LED is On steady and the (red) GEN
FAULT LED is Off. See Figure 18 for LED locations.
Disconnecting power from the Network
Engine
Important: The data protection battery must be
installed and charged before disconnecting the 24
VAC supply power.
Disconnect power from the network engine by removing
the gray 2-pin terminal block from the power terminal
port on the network engine (Figure 3).
When you remove 24 VAC power from the network
engine, or supply power is lost, the network engine is
nonoperational after the power management settings
expire. The POWER LED (Figure 18) remains On, and the
data protection battery continues to power the network
engine for approximately 1 to 3 minutes so that volatile
data can be backed up in nonvolatile memory. The
POWER LED goes Off when the data backup is completed.
Troubleshooting
LED status indicators
The LEDs on the front cover of the network engine
indicate power and communication status. See Figure 18
and Table 10.
LED test sequence at startup
About this task:
During startup, the network engine automatically initiates
an LED test to verify the operational status of the LEDs.
Immediately after connecting supply power, the following
LED lighting sequence occurs:
1. The network engine emits one short beep,
indicating that the BIOS startup was successful.
2. The PEER COM, RUN, and GENL FAULT LEDs turn
on, indicating that the OS is booting up. The FC A
and FC B LEDs also turn on.
3. The PEER COM, RUN, GENL FAULT LEDs, and the
FC A and FC B LEDs shut off. The RUN LED flashes
to indicate that the network engine software is
loading.
4. The LEDs display the operational status of the
network engine. When the RUN LED goes On
Steady, the operating system and Metasys
application are running and the network engine is
ready.
Result
NAE55 Installation Guide 10