114063D RS-232
User’s Manual
INTRODUCTION
This manual is intended to explain the operation of the serial communication protocol for the
“Series E”, “Series IE” and “Series EM” Emergency Lighting Central Inverter. Serial
Communication can be established by means of a computer using terminal emulation software
(such as Tera Term, PuTTy, xterm, etc.), or by any embedded device capable of RS-232 serial
communication. We shall call this device the Client.
The
protocol used is proprietary, and specific to Myers “Series E”, “Series IE” and “Series EM”
Emergency Lighting Central Inverters.
CONNECTION
The Central Inverter has a 9-pin Sub-D (DB9) female connector typically located on the back
(inside) of the front display panel located on the door of the inverter. See below for the exact
location of the connector.
The connection between the Client and the Inverter is a straight-through connection.
Do
not
use a Null Modem Cable that flips pins 2 and 3.
Pin 2 and Pin 3 are the Data send and receive lines; Pin 5 is the Ground (common) line.
Optical isolation on the interface card provides galvanic isolation between the
client device’s
ground signal and the inverter
’s ground.
PC Connector DB-9
“E”, “IE” and “EM” Central Inverter
Connector DB-9
Straight Connection
Pins used = 2,3 5
Illustration 1
– Interconnect Schematic for RS-232 Connection
