Rs-485 Wiring - Honeywell 3400 Installation Instructions Manual

6.7 Honeywell E-Mon Energy RS-485 Wiring
RS-485 communication allows a computer or modem to communicate with one
or more E-Mon Class 3400 Meters. You can connect as many as 52 meters along
a 4000 foot RS-485 cable run. Class 3400 Smart meters are available with your
choice of communication options: Honeywell E-Mon Energy (EZ7) standard,
Modbus, BACnet.
There are three communication protocols available through the E-Mon Class
3400 RS-485 connection. They are EZ7, Modbus RTU, and BACnet MS/TP. The
protocol is chosen when ordering the E-Mon Class 3400 Meter. A second protocol
is available through the Ethernet port. The Ethernet protocol is also chosen when
the meter is ordered. See ordering information for the available choices.
Daisy-Chain Method
This is the simplest method for connecting meters together.
1. Connect the +(high) terminal of PORT 1 of each 3400 meter together so that
the + terminals on all meters are linked, + to + to +...
2. Connect the -(low) terminal of PORT 1 of each 3400 meter together so that
the - terminals on all meters are linked, - to -to ...
3. Connect the GND terminals of PORT 1 to meter 1 ONLY. The GND terminals
should not be linked to each meter.
RS-485
TERMINAL
Fig. 9. Daisy-chain Configuration.
Fig. 10. RS-485 Terminal.
23
E-MON CLASS 3400 METER
M34370
M33274
62-0398—02