MERIDIAN
UNIVERSAL GAS DETECTOR
INSTALLATION
4-39
USE AND DISCLOSURE OF DATA
Information contained herein is classified as EAR99 under the U.S. Export Administration Regulations. Export, reexport or diversion contrary to U.S. law is
prohibited.
6. Connect your MODBUS master input wire signals at TB2 Pin1 (A) and TB2 Pin2 (B) on the terminal/relay/
MODBUS RS-485 PCB.
7. Cable shielding must connect to TB2 Pin3 (S).
8. Route output wiring to next RTU from TB2 Pin4 (A) and TB2 Pin5 (B) (refer to
tions – Terminal/Relay/MODBUS RS-485 PC
).
9. For MODBUS connections to Teledyne Gas & Flame Detection, see
Teledyne Gas & Flame Detection Receivers
.
10. TB2 Pin1 and Pin4 are connected internally as are TB2 Pins2 and Pin5.
11. Insert the lower PCB stack into the housing after wiring the terminal blocks.
12. Insert and tighten the four (4) standoffs.
13. Push the LCD PCB/CPU PCB set into the four (4) standoffs.
14. Install housing cover, tighten and secure the setscrew.
15. When powered up, assign unique RTU address to each of the devices on the MODBUS network using the
MODBUS setup menu (See
Section 5.1.3 Configuring the Setup Menu
).
Figure 4-21: MODBUS Connections – Terminal/Relay/MODBUS RS-485 PC
A B
RS-485 MODBUS
Master
To next RTU
1
2
ALARM3
NO
C
NC
NO
C
NC
FAULT
ALARM1
NC
C
NO
ALARM2
NC
C
NO
RMT
ACK
TERM.
NOT TERM.
LP1
11
1
+ -
LP2
+ -
LP3
+ - B
B
A
A
RS-485
S
10-30VDC
GND
GND
+V
J3= For Last Node
Only
J4= For Node 1, 2, 3, ...
Next To Last Node
DUP
RS-485