Infrared port, Serial communications – SATEC EM720 Operation Manual User Manual
Page 26

Chapter 2 Operating the EM720
Communicating with the EM720
26
EM720 Power Quality and Revenue Meter
the full list of the available communication modules and
communication options.
Infrared Port
The EM720 has an optical infrared port for local meter
reading via a hand-held unit or a portable PC. The IR port can
be equipped with an IEC- or ANSI-compatible optical head on
your selection.
The IR port is identified in the EM720 as port COM1. It is
factory preset to 19200 bps, 8-bits/No-parity data format,
and is pre-programmed for the IEC 62056-21 protocol.
You can change the default baud rate or protocol for the IR
port from the front display or via PAS (see
Serial Communications
Most of the replaceable communication modules you can
order with your EM720 have an additional RS-232/RS-485
serial port. It is easily configurable for either RS-232, or RS-
485 serial communications. See the EM720 Installation
Manual for the serial port wiring.
An RS-232/RS-485 serial port is identified in the EM720 as
port COM3. If you installed communication modules with
more than one serial port, only the port located in the left-
hand slot will be enabled.
The COM3 port is provided with two green RX and TX LEDs
that blink when the port receives or transmits data.
The port is factory preset to 19200 bps, 8-bits/No-parity data
format, and is pre-programmed for the Modbus RTU protocol.
See
Setting Up Serial Communication Ports
on how to change
the factory-set options for your serial port.
You can check the present serial port settings in your meter
via the Device Info display (see
Chapter 3).