Introduction - Endress+Hauser Tankvision Multi Scan NXA83 Operating Instructions Manual

Tankvision
Endress+Hauser
3

Introduction

The Multi Scan NXA83 is a configurable system designed for tank gauging and tank
inventory management systems.
Redundant operation with a pair of Multi Scan NXA83 linked together is supported, so that
only one NXA83 will poll the gauges. The other Multi Scan NXA83 will automatically update
its database with live data from the active Multi Scan NXA83.
This mode of redundancy is called Switch By System and this document outlines the
configuration and operation of the two Multi Scan NXA83.
There are two other modes of redundancy, both of which operate on a single Multi Scan
NXA83 (i.e. not a redundant pair):
• Switch By Gauge: Gauges are configured with two ports (Primary and Backup) on the
same Multi Scan NXA83. If the Multi Scan NXA83 loses connection to a gauge on one port
it will switch to poll the gauge from the other port. This is on an individual gauge basis,
thus both Primary and Backup ports may be polling at the same time.
• Switch By Interface: This is similar the switch by Gauge, except that the Multi Scan
NXA83 will poll ALL gauges on only one port (i.e. Primary on startup). Only when
communication to all gauges has failed on this port will the Multi Scan NXA83 switch to
poll gauges from the other port. Thus the Primary and Backup ports will never poll at the
same time.
This manual is solely concerned with the redundancy functionality, it is assumed that the
user has read the Multi Scan NXA83 manuals and is familiar with configuring a Multi Scan
NXA83 database.
Introduction
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