GE EPM 3000P - Manual (Page 15)

CHAPTER 3
C
OMMUNICATION
I
NSTALLATION
3.1 RS-232C
All EPM3000P and EPM300P-F instruments can be equipped with: the EIA RS-232C or the EIA RS-485.
RS-232C communication links a single instrument with a computer or device such as an RTU or PLC. Its
capability is up to 100 feet. A standard 9-pin female serial port connector mounts on the instrument for
direct connection to a computer with a 9-pin cable.
NOTE: O NLY THREE PINS ARE USED IN RS-232C. (See Figure 3.1).
DB-9 CONNECTOR
A DIRECT PIN-TO-PIN CABLE CAN BE USED.
NO NULL MODEM IS REQUIRED.
COMMUNICATION
CONVERTER
Model
SF-232DB3
8 9 10 11 12 13
7
6
5
4
3
2
1
20
21
22
23
24
25
26
27
28
RS-232 COMMUNICATION CONNECTION
CONNECTION FOR DB-9 FEMALE
PIN 2 - RECEIVE OF THE HOST/COMPUTER
PIN 3 - TRANSMIT OF THE HOST/COMPUTER
PIN 5 - GROUND OF THE HOST/COMPUTER
5 4 3 2 1
9 8 6 7
LAPTOP
DETAIL OF DB-9
BACK VIEW
Figure 3.1 RS-232C Communication Connection Installation
NOTE: T
O AVOID GROUND LOOPS , THE NEUTRAL AND SAFETY GROUND ( PIN 3) SHOULD BE CONNECTED
TOGETHER AT ONLY ONE POINT .
3.2 RS-485
NOTE: T HIS SECTION APPLIES ONLY IF A COMMUNICATION OPTION WAS ORDERED .
Each EPM3000P has an unique address up to four digits long. This allows the user to communicate with
up to 10,000 instruments. Standard baud rates are available up to 4800 baud. To select the proper baud
rate, apply the following rules:
The unit operates up to 4800. For a smaller number of instruments over a long distance,
use a lower baud. Optimal recommended baud rate is 1200 baud if noisy conditions
exist.
10
GE Industrial Systems