Description - ABB PointMaster 200 Series Operating Manual

1 Description

Provided for communication with the multi-point recorder is an
RS 485 interface. The type of data protocol used is designed to
suit DIN 19 245 Part 1 (Profibus protocol). Only a part of the
directives were taken into account. Among others, the directives
on the operation of a multimaster (Token-Passing-Procedures)
were not taken into account, since the recorder is always a
passive subscriber.
2 Technical data for bus connection RS 485
Bus structure
Line without branchings
Stub to subscriber < 0.3 m
Medium
shielded, twisted 2-wire line
surge resistance 100...130 Ω, for f > 100 kHz
Cable capacity < 60 pF/m
Cross section ≥ 0.22 mm
Line length
≤ 1200 m
Number of bus subscribers
32 (active and passive)
Transmission speed
600 / 1200 / 2400 / 4800 / 9600 / 19200 baud
Type of transmission
symmetrical
Driver output
idle state ±5 V, with load ±1.5 V
load resistance 60 Ω
Receiver
sensitivity 200 mV
input resistance 12 kΩ
Grounding
The shield should be grounded on both ends to arrest high
frequency fault states
Potential balancing
Potential variations between the data reference potentials
(GND) of all bus subscribers may not exceed ±7 V
2
Fig. 1 Rear wall with RS 485 interface
Z-18064
Fig. 2 Terminal layout of RS 485 interface
(9-pin connector SUB D)
Z-16529
Pin 1 shielding
Pin 3 RxD (+)
Pin 4 I/O converter (+)
Pin 5 GND (reference potential)
Pin 6 +5 V
Pin 8 RxD (−)
Pin 9 I/O converter (−)
The voltage of +5 V on pin 6 is only required when the recorder
is used as a bus end-unit.
The shielding is applied through a blade-type terminal on the
recorder case.
Description • Technical Data ... 3