Table 10: Network Engine LEDs designation, normal status, description, and other conditions
LED
Normal
Descriptions/Other Conditions
Run (Green)
On Steady
On Steady = network engine software is running.
On 1 second, Off 1 second = network engine software is in startup mode.
On 0.5 seconds, Off 0.5 seconds = network engine software is shutting down.
Off Steady = Operating system is shutting down or software is not running.
24 VAC (Green)
On Steady
On Steady = 24 VAC power is present.
Off Steady = Loss of 24 VAC power. In the Off Steady condition, the network
engine can be running on battery power. Also see the POWER LED.
BATT FAULT (Red)
Off Steady
On Steady = Battery fault. Replace the battery. Battery is not connected
or cannot be charged. The BATT FAULT LED may remain On for up to 24
hours after initially powering on the network engine. If the BATT FAULT LED
remains on longer than 48 hours after initially powering on the network
engine, check the battery connection or replace the battery.
GENL FAULT (Red)
Off Steady
On Steady = General Fault. Fault conditions are user configurable in
software. Preconfigured fault conditions include excessive memory use,
excessive flash use, excessive CPU or PWB temperature, and Battery Fault.
In normal operation, the GENL FAULT LED stays on steady for the first half of
the startup sequence.
Wiring considerations and guidelines for network integrations
Table 11: Network Engine Ethernet network rules
Category
Rules and Maximums
General
Star topology with network switches
Number of Devices
Maximum of 1,000 devices permitted at one site in the Metasys network.
2,000 m (6,600 ft) for plastic/glass fiber optic with external adapter
Line Length and Type
10 BaseT: 100 m (330 ft) Cat5 or Cat6 cable
100 BaseT: 100 m (330 ft) Cat5 or Cat6 cable
1000 BaseT: 100 m (330 ft) Cat5E or Cat6 cable
Terminations
For 10/100/1000 BaseT, no line terminators allowed.
Table 12: Guidelines for BACnet protocol MS/TP network topology
Category
Rules and Maximums
General
Two MS/TP Bus trunks, daisy chain topology only. No T or star topology configurations.
Number of Devices
100 devices per FC Bus with no more than two repeaters between network engine and any
device and a maximum of 50 devices between repeaters
Note:
If TEC2000 Series Thermostat Controllers or third-party devices are used on the
FC Bus, the maximum total number of devices is 64 and the maximum length is 1,219 m
(4,000 ft).
1,500 m (5,000 ft) cable without a repeater
4,500 m (15,000 ft) cable from network engine to the farthest FC Bus device (three bus
segments of 1,500 m [5,000 ft] each, separated by repeaters)
Line Length and Type
2,000 m (6,600 ft) between two fiber modems
Cable Type
Stranded 0.6 mm (22 AWG) 3-wire twisted, shielded cable is recommended.
Stranded 0.6 mm (22 AWG) shielded 4-wire (two twisted-pairs) shielded cable is acceptable.
Note:
Use only twisted pair wire. On applications using 4-wire (two twisted-pairs) cable,
isolate and insulate unused conductor. Refer to the
MS/TP Communications Bus Technical
Bulletin (LIT-12011034)
for more information.
NAE55 Installation Guide
12