Owner's manual

Choosing Module Features
Chapter 3
34
AB Long Line
Use A-B Long Line for communicating up to 5000 cable feet between an
industrial terminal, serving as an ASCII device, and the ASCII module.
Refer to Table 2.D for a detailed listing of A-B Long Line pin functions.
Table 2.D
AB
Long Line Connector Pin Functions
Pin No.
Signal Name Source Function
2 T ransmitted Data AB Long Line Device Data T ransfer to 1771DA
7 T ransmitted Data Return Return for transmitted data
11 Received Data 1771DA Data transfer to AB Long Line Device
25 Received Data Return Return for received data
Selecting the Communication Mode
The communication mode that you choose depends on the cable distance
from your ASCII device to your ASCII module, and on characteristics of
your ASCII device (Table 2.E).
Table 2.E
Mode
of Communication
If Distance is
Less Than
And Y our ASCII Device is a
Then Choose this
T ransmission Mode
50 feet Data T erminal Equipment (DTE) and conforms
to RS232C
without control lines
with control lines
Data Set (modem) and conforms to RS232C
without control lines
with control lines
RS232C (Figure 2.1)
4wire cable
8wire cable
RS232C (Figure 2.2)
4wire cable
8wire cable
500 feet DTE and provides a 20mA current source for
the transmit line, only
DTE and requires a 20mA external current
source for its transmit line
DTE and provides 20mA current sources for
transmit and receive lines
Current Loop (Figure 2.3)
The module powers its own transmit line.
Current Loop (Figure 2.4)
Y ou add the power supply for the DTE.
Current Loop (Figure 2.5)
The module operates in passive transmit.
5000 feet AB industrial terminal or contains a line driver
receiver for AB long line operation.
AB Long Line (Figure 2.6)