Det-Tronics EA2100CG Eagle 2000 Communication Gateway - Manual (Page 13)

Section IV
EA2100CG
Communication Gateway
APPLICATION
The gateway provides the communication link between a
Det-Tronics addressable detector and the host device.
Registers in the gateway are used for passing information
between the host and communication modules. The gate-
way communicates with the host device through a serial
interface port (RS232 or RS422) using Modbus protocol.
Local annunciation capability is provided utilizing a three
digit display, LEDs and a twenty segment bar graph dis-
play. When a detector is in alarm or when a calibration
or fault event occurs, the detector’s address and detec-
tor type are identified on the digital display, and the per-
centage of full scale is indicated on the bar graph.
FEATURES
• Utilizes industry standard Modbus protocol
• Bar graph and digital displays
• Alarm, calibrate and fault LEDs
• Transformer isolation of network ports
• Programmable relay outputs
• Mounts in standard Q4004 rack
• Multiple gateways to enhance reliability or support
additional host devices
• EMI/RFI hardened.
SPECIFICATIONS
INPUT VOLTAGE—
18 to 32 vdc.
POWER CONSUMPTION—
Operating: 325 ma at 24 vdc maximum.
Startup: 1.0 ampere at 24 vdc, momentary.
I/O PORTS—
Host Port: The gateway is a “Modbus slave” device and
communicates with a host device through a serial port
using Modbus protocol. The serial port provided for the
host can be configured as either RS232 or RS422.
Network Port: Two 78.5 kbps communication ports pro-
vide the start and end of the loop upon which the sen-
sors and their communication modules reside. The loop
wiring is level 4, 22 AWG shielded twisted pair. The
wiring is transformer coupled to protect the transceivers.
TEMPERATURE RANGE—
+32°F to +140°F (0°C to +60°C).
HUMIDITY RANGE—
0 to 90% RH, non-condensing.
SHIPPING WEIGHT (Approximate)—
2.6 lb (1.2 kg).
DIMENSIONS—
See Figure 9.
DESCRIPTION
The Eagle gateway transmits information from the com-
munication modules to any device that can act as a
Modbus Master. This interface between the gateway
and host device conforms to the Modbus RTU standard.
For systems requiring a higher throughput than the
Modbus 19.2 kbaud standard, the EagleVision Operator
Interface Station can connect to the gateway at 57.6
kbaud.
The Eagle system is designed to operate with up to 4 gate-
ways (one main and three auxiliary) on a single communi-
cation loop. Each gateway is configured by DIP switches
to function either as a “main” or an “auxiliary” gateway.
Both gateways contain identical software and hardware
and differ only in respect to their function within the system.
MAIN GATEWAY
The main gateway is used by the host device to perform
device configuration. It also generates a periodic time
and date broadcast as well as a heartbeat signal on the
communication loop for use by the devices on the loop
in their fault isolation schemes. As long as wiring
integrity is maintained, all “normal” gateway initiated
communication on the loop originates from the primary
communication port (Com. 1). If a fault occurs, commu-
nication takes place from both the primary and the sec-
ondary communication port (Com. 2).
A relay in the gateway terminates the communication
wiring during normal operation. In the event of a power
loss, a communication pass-through circuit is created.
9 95-8424
9.3 (23.6)
2.0
(5.0)
7.0
(17.8)
A1496
Figure 9—Gateway Dimensions in Inches (Centimeters)