NorthStar Navigation 491 installation manual Section ONE Introduction, Welcome to the Northstar

SECTION ONE — Introduction

Welcome to the Northstar 491

An echo sounder is a device that provides information about the water directly beneath a vessel. The Northstar echo sounder system consists of:

•the Northstar 491 echo sounder sensor

•a Northstar navigation system such as the 962, 958 or 6000i

•a transducer

The 491 can be used with either a single-element transducer or a dual-element transducer. The 491 automatically pings both transmitters at power-up to determine the number of transducer elements connected. If a single element is detected, the 491 operates in single-frequency or dual-frequency interleaved mode (as determined by the operator) at 600 Watts. If two elements are detected, the 491 uses both elements at 1000 Watts.

Installation and setup procedures are different for the two basic types of Northstar navigators. The following terminology should be carefully fol- lowed:

•the term 961/962 indicates instructions that apply to the Northstar 961 and the 962 navigators

•the term 957/958/6000i is used for these units

•the term navigator by itself identifies information that applies to all units

Who should read this manual

Scope of this manual

This manual is for marine technicians who are installing the Northstar 491 and connecting it to a Northstar navigator and a transducer.

In this manual, you’ll find information about the following:

•mounting and wiring the 491

•connecting the 491 to the Northstar navigator

•installing a transducer (an overview is provided, but for such details as wiring, see the documentation provided by the transducer’s man- ufacturer)

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