Electrical Connections
ELECTRICAL CONNECTIONS
HARDWARE INSTALLATION
1 Unpack materials: Remove all materials from shipping box and verify all required components are available
2 An antenna inside a non-metallic enclosure will be required Metal enclosures restrict RF communications If a metal
enclosure is required, use an external antenna and an RF antenna cable
3 Connect the pulse output devices For KYZ pulse output meters, attach the normally-open circuit to the R9120-5
transceiver These are usually the K and Z terminals
4 Connect the RS485 Modbus network loop as shown in the wiring diagram Follow the manufacturer’s instructions for
installing and powering other Modbus devices Verify that the Modbus address settings are unique for each device (no two
devices with the same address) Connect each device in the chain by “daisy-chaining” the devices together Observe
+ and – polarity on the Modbus devices
Do not ground the RS485 shield inside an electrical panel All RS485 and 24V DC power wires, including the shield should be
insulated to prevent accidental contact to high voltage conductors
The pulse, RS485 and power cable should be mechanically secured where it enters the electrical panel
Insulate the wire used to provide pulse and RS485 communications to meet requirements of the voltages present inside
any box the wire is mounted within For example, Belden 1120A has a 600V insulation rating and can be used in many
applications Check with your electrical installer for details as local code requirements may vary
WARNING: AFTER WIRING THE R9120-5 TRANSCEIVER, REMOVE ALL SCRAPS OF WIRE OR FOIL SHIELD FROM THE
ELECTRICAL PANEL. IT COULD BE DANGEROUS IF WIRE SCRAPS COME INTO CONTACT WITH HIGH VOLTAGE WIRES.
5 Attach the antenna to the R9120-5 transceiver When using an antenna cable, avoid sharp bends; kinks in the antenna
cable will degrade performance
6 Attach the power to the R9120-5 transceiver and apply power Observe the LEDs to confirm the device is operating
◊ Alive (green)
: blinks once per second while the system is operating correctly
◊ RS485 RX
: The RX LED should blink whenever a Modbus query is sent on the RS485 loop (regardless of the target
address of the query) If the R9120-5 transceiver is attached to a Model 3700 data acquisition server, the RX LED should
blink about once per second
◊ RS485 TX
: The TX LED will blink when the A89DC-08 responds to a Modbus query
OTEE:
N
If cleaning is required, use a dry towel to remove dust from the R9120-5 transceiver
Do not use fluids to clean the R9120-5 transceiver
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June 2016
XMT-UM-02107-EN-01