Impulse 1103 - Manual (Page 3)

Introduction
Sealevel Systems IC485+I Page 1
Introduction
Overview
The Sealevel Systems IC485+I is an isolated single channel RS-232 to RS-422/485 asynchronous converter. It
provides one field selectable RS-422/485 serial port supporting asynchronous data rates up to 115.2K bps. The
IC485+I is self-powered allowing it to correctly drive multi-drop RS-485 networks.
Isolation is important in installations where the equipment being connected to the PC is either far from the PC, or on
a different power transformer circuit. Ground loop current is a commonly neglected and misunderstood phenomenon
that leads to data loss and the destruction of communications interfaces.
Configure the port as RS-422 for long distance device connections up to 4000ft. where noise immunity and high data
integrity are essential. Select RS-485 and capture data from multiple peripherals in an RS-485 multi-drop network.
Up to 31 RS-485 devices can be connected to automate your data collection.
In RS-422 and RS-485 Auto modes, the card works seamlessly with the standard operating system serial driver. Two
additional methods are provided to control the communication line in RS-485 mode. The “Data Enable” mode uses
the transmitted data to enable the transmitter and requires no software drivers. This mode has limitations that will be
discussed in more detail later. The “RTS Enable” mode uses the UART modem control signal RTS to control the
communication line and requires the Sealevel Systems’ serial driver.
What’s Included
The IC485+I is shipped with the following items. If any of these items is missing or damaged, contact the supplier.
• IC485+I Serial I/O Adapter
• Sealevel Software CD
• Power Supply
Factory Default Settings
The IC485+I factory default settings are as follows:
Port # Electrical Specification
Port 1 RS-422
To install the IC485+I using factory default settings, refer to Installation.
For your reference, record installed IC485+I settings below:
Port # Electrical Specification
Port 1