Micromod MOD: 1732N, 1733N External Mini-Link Users Guide - Manual (Page 6)

IB-23C004
INTRODUCTION
Physically the Mini Link/EXT is a standalone interface box with two serial port connections
for host PC communications and up to two network connections for ICN communications
to MOD 30 and MODCELL instruments. The base configuration consists of:
• Two Serial Ports
The two RS-232C serial ports (one DB9 and one DB25) have individually configurable
baud rates in the range of 300 to 19200 bps. The standard protocol is: Parity - None,
Data Length - 8 bits, Stop Bits - 1. The second serial port could be used to provide
redundant control of the instrument system.
• One Instrument Communications Network Controller
The base ICN Controller is accessed via a two-wire or three-wire connection at the
rear of the box using the three screw terminal block at the connection marked "ICN0".
Communication can be maintained between the personal computer and up to 15 field
instruments.
• Optical Isolation Between Instruments and Personal Computer
The optical isolation feature is jumper-selectable (see Section 2.3, Jumper Settings)
and provides a minimum of 3000 Vdc electrical insulation between the Instrument
Communications Network and the personal computer. THIS FEATURE IS NOT
FACTORY SET.
• External Pushbutton Reset
A 750ms reset pulse can be issued to the External Mini Link by pressing the reset
button located at the rear of the box. The button is prominently labeled "RESET".
• Front Panel Indicators
The front panel of the External Mini Link is divided into two sections labled ICN0 and
ICN1. Each section has three LED indicators as described below:
ENABLED When lit, this LED indicates that the circuit controlling the instru-
ment communications through the corresponding ICN is active and
responding properly to the main processor.
RCV This LED flashes during instrument to Mini Link/EXT digital com-
munications.
SEND This LED flashes during Mini Link/EXT to instrument digital com-
munications.
The 1733N Mini Link/EXT can be enhanced with a 1732N ICN Interface Board to provide
communications access to an additional 15 field instruments. This daughter board is
mounted to the External Mini Link board and is accessed via a two- or three-wire
connection at the rear of the box using the three-screw terminal block at the connection
marked "ICN1".
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