Det-Tronics EA2100CG Eagle 2000 Communication Gateway - Manual (Page 20)

ADDRESSABILITY
Relay module identification is accomplished by setting
rocker switches on an eight position DIP switch located on
the electronic module. Valid addresses are from 5 to 110.
NOTE
Each relay module constitutes a node on the com-
munication loop and counts as one of the 250
nodes maximum allowed on the total communica-
tion loop.
EVENT LOGGING
The relay module maintains a log of the eight most
recent alarm events. Time and date are logged for each
alarm. A maximum of eight events can be stored. If
more than eight alarm events are logged, the oldest
events will be lost.
STATUS LEDs
Three LEDs are located at the center of the PC board on
the electronic module. (The cover must be removed
from the enclosure in order to view the LEDs.)
The green LED serves as a power-on indicator and is
illuminated whenever power is applied. During normal
operation, only the green LED is on.
The red LED indicates an alarm or fault condition. The
flashing rate of the red LED indicates the following con-
ditions:
On steady = Alarm condition
Blinking = Fault condition.
An alarm condition has priority over a fault condition.
The amber LED is provided for factory diagnostic purpos-
es and is not normally used in the field. A flashing amber
LED indicates a problem with the communication chip.
FAULT TOLERANT NETWORK
The relay module utilizes the same unique fault isolation
technique for detecting a network wiring fault as the
Eagle communication modules. The relay module con-
tains both the software and hardware to isolate it in the
event of a wiring fault. This allows communication to
continue through the remainder of the network.
WIRING
The serial communication loop is wired using level 4, 22
AWG shielded twisted pair wire. Wiring for power,
inputs and outputs must be 18 AWG minimum.
All external wiring is connected to screw terminal con-
nectors on the terminal wiring board that is factory
mounted inside the enclosure. The electronic module is
mounted inside the enclosure above the terminal wiring
board and is connected to the terminal wiring board
with a ribbon cable.
ENCLOSURE
The watertight, explosion-proof aluminum enclosure is
designed for use in Class I, Division 1, Groups B, C and
D hazardous locations. It is designed to meet CEN-
ELEC requirements for EEx d IIC T5 hazardous loca-
tions, and is IP66 rated.
The enclosure is furnished with two 3/4 inch NPT con-
duit entries.
Section VII
System Installation
GENERAL WIRING REQUIREMENTS
NOTE
The wiring procedures in this manual are intended
to ensure proper functioning of the device under
normal conditions. However, because of the many
variations in wiring codes and regulations, total
compliance to these ordinances cannot be guaran-
teed. Be certain that all wiring complies with appli-
cable regulations that relate to the installation of
electrical equipment in a hazardous area. If in
doubt, consult a qualified official before wiring the
system.
All devices on the Eagle communication network are
wired in a serial loop that starts and ends at the gate-
way. The use of 22 AWG level 4 shielded twisted pair
cable is required for wiring the communication network.
For other system wiring, 18 AWG minimum is recom-
mended. All shields should be grounded at only one
end to prevent ground currents.
NOTE
The recommended procedure for grounding the
shields of the communication loop wiring requires
the shields to be connected to each other inside
the enclosure of each device on the loop, ensuring
continuity of all shields on the loop. However, to
prevent ground currents from flowing through the
shield, the ends of the shield must be left discon-
nected at a single point on the loop (typically at a
node midway around the loop). The shields must
not be connected to earth ground at any of the
device enclosures. The two shield ends are con-
nected to earth ground at the gateway (Figure 15).
16