Electrical Installation; Selection Of Serial Communication Adaptors For Personal Computers; Recommended Opto22 Boards; Pull-Up And Pull-Down Resistors - ABB C1300 User Manual Supplement

C1300
Advanced Circular Chart Recorder

2 Electrical Installation

2.1 Selection of Serial Communication Adaptors for Personal Computers

Note.

An RS422/485 communication board is required in the host PC.

Observe the limitations outlined in the Installation Guide – the maximum serial data transmission line length for both RS422
and RS485 systems is 1200m (3,937 ft).
An RS422/485 communications adaptor is required for serial links. Ensure that the card used has galvanic isolation to protect the
computer from lightning damage and increase its immunity to noise pick-up.

2.2 Recommended OPTO22 Boards

The following OPTO22 boards are recommended for use with the C1300:
Part No. Computer Type
AC24 AT AT Bus IBM® PC compatible
AC34 Microchannel IBM® PC

2.3 Pull-up and Pull-down Resistors

o prevent false triggering of the slave (C1300) by the presence of noise when the master (host computer) is inactive, 1.8k pull-up
and pull-down resistors must be fitted to the RS422/485 adaptor card – see Figs. 2.1 and 2.2.
C1300
Pull-up and Pull-down Resistors
'B'
1.8kW Pull-up
Resistor
'A
+5V
'B'
'A'
0V
1.8kW Pull-down
Resistor
Linked In
– see Note Linked Out
6
7
8 5
9
10
Links on Serial Module
Fig. 2.1 Pull-up and Pull-down Resistors (3-wire Operation)
IM/C1300–MOD Rev. C
Serial Module
Terminal Board
1
Tx–/Rx–
2
Tx+/Rx+
3
4
5
6
7
8
9
4
3
Tx+
Tx–
Tx+
Rx+
Rx–
Tx–
GND
GND
Note. If an RS422/485 adaptor card without pull-up and
pull-down resistors is used, the C1300's internal resistors
can be linked in.
2 Electrical Installation
Computer Terminal or Host Computer
'B'
'A'
+5V +5V
1.8kW Pull-up Resistor
'B'
'A'
1.8kW Pull-down Resistor
0V
3