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,
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.
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.
Fig. 9. Daisy-chain Configuration.
Fig. 10. RS-485 Terminal.
E-MON CLASS 3400 METER