ABB AnalyzeIT ZMT Series, Дополнительные инструкции по эксплуатации

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3
3.1 Serial Communication
Adaptors for Personal Computers
An RS422/485 communications adaptor board is required for
serial links. It is strongly recommended that the card used has
galvanic isolation to protect the computer from lightning
damage and increase immunity from noise pick-up from
cables.
3.1.1 Configuration
The following OPTO22 boards are recommended for use with
the serial version of ZMT analyzers:
Part No. Computer Type
AC24 XT Bus IBM PC compatible
AC24 AT AT Bus IBM PC compatible
AC34 Microchannel IBM PC.
The following ‘Jumper’ selections are required on OPTO22
boards (usually supplied as the default configuration):
RX & TX install line termination jumper
Install pull-up and pull-down
jumpers
CTS & RTS disable jumper installed.
Select board address and interrupts as described in the
OPTO22 manual.
All connections, apart from those for serial data
communication, are made as shown in Figs. 5.4 and 5.5 of the
Operating Instructions (IM/ZMT).
4.1 Serial Connections – Figs. 4.1 and 4.2
The transmitters must be connected in parallel as shown in the
schematic diagram – Fig. 4.1. The RS485 standard quotes
connection of maximum thirty two slaves (ZMT Analyzers) to
any single driver (computer terminal or host computer); the
RS422 standard quotes connection of up to ten slaves.
However, these numbers can be increased if the driver’s serial
port permits.
Make serial data connections as shown in Fig. 4.2. The type of
cable used is dependent on the transmission speed and cable
length:
4.1.1 Cabling (refer also to Fig. 9.1 on page 13)
Up to 6m (all speeds) – standard screened or twisted pair
cable.
Up to 300m – twin twisted pair with overall foil screen and
an integral drain wire, e.g. Belden 9502 or equivalent
Up to 1200m – twin twisted pair with separate foil screens
and integral drain wires for each pair, e.g. Belden 9729 or
equivalent
Fig. 4.1 Schematic Diagram
3 INSTALLATION 4 ELECTRICAL CONNECTIONS
Chain of ZMT Analyzers
Connected
Termination Resistor
(on ZMT receive input)
Computer Terminal or
Host Computer
Last ZMT
in Chain
Fig. 4.2 Serial Connections
1 2 3
Output Module 3
4 5 6
Tx
TB
Tx Rx
From PC
Rx 0V
Rx Rx Tx Tx 0V