Raymarine DSM250 User Manual

DSM250

Digital Sounder
Module

Owner’s
Handbook

Document number: 81211_1
Date: December 2002

DSM250 Digital Sounder Module iii

DSM250 Digital Sounder Module Owner’s Handbook

December 2002

Intended Use

Raymarine DSM250 Digital Sounder Modules provide echo
sounder data that can be displayed on Raymarine PLUS Radar,
Chartplotter, or Fishfinder display units. DSM250 Digital
Sounder Modules are intended for recreational depth finding and
fishfinding purposes.

SAFETY NOTICES

This equipment must be installed and operated in accordance with
the instructions contained in this manual. Failure to do so can
result in personal injury and/or navigational inaccuracies. In par­ticular:

HIGH VOLTAGE. The DSM250 contains high voltages. Adjust­ments require specialized service procedures and tools only avail­able to qualified service technicians – there are no user
serviceable parts or adjustments. The operator should never

remove the cover or attempt to service the equipment.

CAUTION:

Removing the transducer cable from the rear of the DSM250
while the sounder module is powered on can cause sparks. Only
remove the transducer cable after power has been removed from
the DSM250. As with any electronic device, be sure the sounder
module is mounted where it is well ventilated and free from
gasoline fumes.

If the transducer cable is accidentally removed while the DSM250
is powered on, remove power from the sounder module, replace
the transducer cable, and then return power to the module. As a
safety feature, the DSM250 only recognizes that the transducer is
connected at power-up.

iv DSM250 Digital Sounder Module

EMC Conformance

All Raymarine equipment and accessories are designed to the best
industry standards for use in the recreational marine environment.

The design and manufacture of Raymarine equipment and acces­sories conform to the appropriate Electromagnetic Compatibility
(EMC) standards, but correct installation is required to ensure that
performance is not compromised.

Preface

This handbook describes the Raymarine DSM250 Digital
Sounder Module (200/50 kHz).

This device must be connected to an
ter, or Fishfinder display unit to show echo sounder data. The
DSM250 will not work with older HSB (non-PLUS) displays.

Note: Older HSB (non-PLUS) display units must be upgraded to
before they can function with the DSM250.

Echo sounder systems require an appropriate Raymarine trans­ducer unit and inter-connecting cable. Details for selecting and
installing the transducer are described in document number
81196, Transducers for Fishfinders Owner’s Handbook.

2

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PLUS Radar, Chartplot-

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2

This handbook contains very important information on the instal­lation and operation of your new equipment. In order to obtain the
best results in operation and performance, please read this hand­book thoroughly.

Raymarine’s Technical Services representatives or your local
dealer will be available to answer any questions you may have.

Conventions

Raymarine echo sounding (sonar) devices with integrated dis­plays are known as Fishfinders. In this document, the DSM250—
which does not have its own display—is alternatively called a
Digital Sounder Module, Sounder, or just Module. The DSM250’s
image data can be viewed on a display unit when that display is in
Sonar Mode.

DSM250 Digital Sounder Module v

Throughout this handbook, the dedicated (labelled) keys are
shown in bold capitals; for example, MENU. The soft key func­tions, menu names and options are shown in normal capitals; for
example, SCREEN.

Operating procedures, which may consist of a single key-press or
a sequence of numbered steps, are indicated by a ➤ symbol in the
margin. When the procedure requires you to press a soft key, the
soft key icon is shown in the margin.

Technical Accuracy

The technical and graphical information contained in this hand­book, to the best of our knowledge, was correct as it went to press.
However, the Raymarine policy of continuous improvement and
updating may change product specifications without prior notice.
As a result, unavoidable differences between the product and
handbook may occur from time to time, for which liability cannot
be accepted by Raymarine.

Warranty

To register your DSM250 Digital Sounder Module ownership,
please take a few minutes to fill out the warranty registration card
found at the end of this handbook. It is very important that you
complete the owner information and return the card to the factory
in order to receive full warranty benefits.

Raymarine Products and Services

Raymarine products are supported by a network of Authorized
Service Representatives. For information on Raymarine products
and services, contact either of the following:

United States Raymarine, Inc.

22 Cotton Road, Unit D
Nashua, NH 03063-4219
USA
Telephone:[phone]

1-800-539-5539

Fax: [phone]

vi DSM250 Digital Sounder Module

Europe Raymarine Ltd

Anchorage Park
Portsmouth, Hampshire
England PO3 5TD
Telephone: [phone]
Fax: [phone]

Or, you may contact us on the World Wide Web at:

www.raymarine.com

This product contains technology provided under license by
Acorn Group plc. The copyright of this intellectual property is
acknowledged by Raymarine, Inc. as are Acorn’s trademarks and
patents. Acorn’s world wide web address is www.acorn.com.

Raymarine is a registered trademark of Raymarine Limited.
SeaTalk is a registered trademark of Raymarine Limited.

2

hsb

is a trademark of Raymarine Limited.

Pathfinder PLUS is a trademark of Raymarine Limited.

© Raymarine, Inc. 2002

DSM250 Digital Sounder Module vii

Contents

SAFETY NOTICES ........................................................iii

EMC Conformance .......................................................... iv

Warranty ............................................................................ v

Raymarine Products and Services ..................................... v

Chapter 1: Overview .................................................................. 1-1

1.1 Introduction .......................................................... 1-1

How to Use This Handbook ...........................................1-2

What's New ....................................................................1-3

General ...........................................................................1-4

Sonar Mode Display Features ........................................1-5

1.2 Sonar Mode Display ............................................. 1-5

Operating Modes ...........................................................1-7

Sonar Options ................................................................1-8

Sounder Functions .........................................................1-9

Chapter 2: Installation .............................................................. 2-1

2.1 Introduction .......................................................... 2-1

Planning the Installation ................................................ 2-2

EMC Installation Guidelines .........................................2-2

2.2 Unpacking and Inspecting the Components ......... 2-4

2.3 Selecting the Equipment Location ........................ 2-4

Sounder Module Mounting Location ............................2-4

2.4 Cable Runs ............................................................ 2-5

2.5 Mounting the Sounder Module ............................. 2-8

2.6 System Connections ............................................. 2-9

DC Power Connection .................................................2-10

Ground Connection ......................................................2-11

2

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Connection ............................................................2-12

Transducer Connection ................................................2-13

viii DSM250 Digital Sounder Module

EMC Conformance ......................................................2-15

Chapter 3: Getting Started ....................................................... 3-1

3.1 Introduction ...........................................................3-1

3.2 Powering on the Sounder Module ......................... 3-1

Status LED .....................................................................3-1

3.3 Updating Software on the Display Unit ................3-2

3.4 Selecting Repeater Mode ......................................3-2

3.5 Selecting Sonar Mode ...........................................3-3

3.6 Simulator Mode .....................................................3-5

Viewing Simulator Data .................................................3-6

Chapter 4: System Setup ........................................................... 4-1

4.1 Introduction ...........................................................4-1

4.2 Changing the Set Up Parameters ...........................4-1

4.3 System Set Up Parameters ....................................4-3

Data Boxes .....................................................................4-5

Bearing Mode .................................................................4-6

Cursor Reference ...........................................................4-6

Cursor Readout ..............................................................4-6

Day/Night ......................................................................4-6

Help ................................................................................4-7

Soft Keys ........................................................................4-7

Key Beep ........................................................................4-7

MOB Data ......................................................................4-7

Autopilot Pop Up ...........................................................4-7

Menu Timeout Period ....................................................4-7

Units ...............................................................................4-8

Variation Source .............................................................4-8

Bridge NMEA Heading .................................................4-9

NMEA-Out Set Up ........................................................4-9

Cursor Echo .................................................................4-11

DSM250 Digital Sounder Module ix

Date and Time Settings ................................................4-11

GPS SOG/COG Filter ..................................................4-12

Compass Set Up ...........................................................4-12

Language ......................................................................4-12

Simulator ......................................................................4-12

4.4 Sonar Set Up Parameters ..................................... 4-13

Target Depth ID ............................................................4-14

Color Bar ......................................................................4-14

Depth Digit Size ...........................................................4-14

Sonar HSB Mode .........................................................4-14

Depth Offset .................................................................4-15

Speed Calibrate ............................................................4-16

Temperature Calibrate .................................................4-16

Sonar History ...............................................................4-16

Sonar Interference Rejection .......................................4-16

Sonar Simulator ...........................................................4-17

Version/Serial Numbers ...............................................4-17

Chapter 5: Basic Display Controls ............................................ 5-1

5.1 Introduction .......................................................... 5-1

Simulator ........................................................................5-1

5.2 Setting Color and Brightness ................................ 5-1

Lighting and Contrast (Monochrome Displays) ............5-1

Brightness and Color Settings (Color Displays) ............5-2

5.3 Controlling the Display ......................................... 5-5

Selecting the Display Mode ...........................................5-6

Switching Between Sounder and Other Modes ...........5-12

5.4 Display Control Functions .................................. 5-13

Viewing Data Boxes ....................................................5-14

Changing the Scroll Speed ...........................................5-14

Selecting the Power Setting .........................................5-15

Changing the Sounder Range ......................................5-16

Selecting the Frequency ...............................................5-19

Using Bottom Lock ......................................................5-20

Using A-Scope .............................................................5-22

x DSM250 Digital Sounder Module

Using Zoom .................................................................5-24

Chapter 6: Sonar Mode Operation ........................................... 6-1

6.1 Introduction ...........................................................6-1

6.2 Interpreting and Adjusting the Sounder Image .....6-1

Fish Indications ..............................................................6-2

Bottom Indications .........................................................6-3

Using White Line ...........................................................6-5

Adjusting Display Gain (Sensitivity) .............................6-5

Using Alarms .................................................................6-8

6.3 Using VRM to Determine Depth & Distance from

Vessel ...................................................................6-10

6.4 Waypoints ............................................................6-12

Placing a Waypoint ......................................................6-13

6.5 MOB ....................................................................6-14

Chapter 7: Maintenance and Problem Solving ...................... 7-1

7.1 Maintenance ..........................................................7-1

Routine Checks ..............................................................7-1

Cleaning Instructions .....................................................7-1

EMC Servicing and Safety Guidelines ..........................7-2

7.2 Resetting the System .............................................7-3

7.3 Problem Solving ....................................................7-4

Status LED .....................................................................7-6

How to Contact Raymarine ............................................7-7

Worldwide Support ......................................................7-10

Appendix: Specifications ........................................................A-1

Chapter 1: Overview 1-1

Chapter 1: Overview

1.1 Introduction

This handbook describes the DSM250 Digital Sounder Module.
The DSM250 receives sonar signals from a transducer mounted in
the water and transmits data via
or Chartplotter display unit already installed in your vessel, elimi­nating the need for a separate display unit. You may also connect
the module to an existing PLUS Fishfinder display for improved
performance.

Note: Older HSB (non-PLUS) display units must be upgraded to
before they can function with the DSM250.

2

hsb

to a Pathfinder PLUS Radar

hsb

2

-1

9

5

1

6

D

Figure 1-1: DSM250 Digital Sounder Module

The DSM250 employs a very high transmission repetition or
“ping” rate which, along with the digital adaptive high sample
rate receiver, ensures that fish and bottom structure are presented
in superb detail and optimal color allocation (in color LCD dis­plays). The DSM250 digital bandwidth adaptation adjusts the
receiver band width dynamically from very wide to very narrow,
as required by the actual water conditions. This provides superior
fish and bottom detection in conditions where other fishfinders
see very little or nothing at all.

1-2 DSM250 Digital Sounder Module

The DSM250 features dual frequency (200 kHz and 50 kHz)
operation and—depending on the transducer installed and condi­tions—up to 1000 watts RMS output power and performance
from 3 ft (1m) up to 5000 ft (1700 m).

This handbook describes DSM250 functions and how to use

hsb

PLUS Radar, Chartplotter, or Fishfinder display unit controls to
operate sonar operations. Controls that are specific to either
Radar, Chartplotter, or Fishfinder display unit functions are not
described in this document but can be found in the handbook for
that display.

Note: Many illustrations in this handbook show example screens.
The screen you see on your display depends on your system configu­ration and set up options, so it may differ from the illustration.

How to Use This Handbook

If you are installing the DSM250 yourself, you should read
Chapter 2 before you start the installation.

For an overview of the display unit controls, read Chapter 5.

Chapter 3 will help you start using your system.

For detailed information on sounder module operations, refer to
Chapter 6.

2

To change the system set up default settings, read Chapter 4.

Chapter 1 gives an overview of the display unit controls and
sonar operation.

Chapter 2 provides planning considerations and detailed instruc­tions for installing the DSM250 and connecting the unit to the dis­play unit via

hsb

2

.

Chapter 3 provides instructions for setting up your system to suit
your preferences. You should read this chapter to determine how
to change the sonar system from the default settings.

Chapter 4 shows how to start using the display and viewing sonar
echo data.

Chapter 5 details operating the display unit’s controls in Sonar
mode.

Chapter 1: Overview 1-3

Chapters 6 provides detailed information for operating the sonar
functions - selecting depth range limits, adjusting gain, color and
STC, setting alarms, using the VRM marker, marks and man over­board.

Chapter 7 provides information on user maintenance, and what
to do if you experience problems.

The Appendix lists the technical specifications for the DSM250.

What's New

The DSM250 operates much like traditional Raymarine fishfind­ers. If you are already familiar with our displays, you won’t have
much difficulty using the DSM250. Below is a list of DSM250
features that differ from our traditional fishfinder displays.

• No integral display. You connect the DSM250 to an

Radar, Chartplotter, or Fishfinder display unit to show echo
sounder data.

• Digital sonar. The DSM250 employs a digital dynamic adaptive

receiver and transmitter for dramatically improved fish and bot­tom detection in any water conditions.

• New automatic Gain modes. These automatic modes make the

gain adjustments for you, based on depth and water conditions.
The DSM250 provides three pre-defined automatic gain settings
for Cruising, Trolling, and Fishing. See Adjusting Display Gain
(Sensitivity) on page 6-5.

• Bottom hunt feature. The DSM250 features a digital “Hunt

mode” that automatically searches for the bottom when the
sounder is in Auto Range. Unlike our fishfinder displays, the
DSM250 stays in manual range when placed there—it does not
switch to auto mode by itself. When you are trying to automati­cally find bottom, you need to have the sounder module set to
Auto Range mode. Refer to Hunt Mode on page 5-18.

• Auto frequency. When set to Auto Frequency, the DSM250 also

alternates frequencies when hunting for bottom. If set for Manual
frequency, the unit does not switch frequencies when bottom
hunting. This differs from traditional Raymarine fishfinder dis­plays. Details are found in Selecting the Frequency on page 5-19.

• New Auto STC mode. You can now let the sounder unit automat-

ically choose the optimal STC level for reducing background
noise that often appears in shallow water. See STC on page 6-8.

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2

PLUS

1-4 DSM250 Digital Sounder Module

• Transducer detection. For safety reasons, if the transducer is

disconnected and then reconnected while the sounder is powered
on, the DSM250 does not detect that the transducer has been re­attached. In this case, you must power down the DSM250, recon­nect the transducer cable, and then power the sounder module
back on before it operates properly.

• Status LED. The LED on the connector panel provides valuable

status information. The LED blinks green while the module is
operating normally. If the unit detects a problem, the LED blinks
amber to indicate a warning or red for an error. The number of
times the LED blinks is a code representing the nature of the prob­lem. Refer to Status LED on page 7-6.

General

The DSM250 system, illustrated below, is comprised of the Dig­ital Sounder Module, an

2

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PLUS Radar, Chartplotter, or Fish-

finder display unit, transducer, and associated cables.

Transducer

Digital Sounder Module

hsb

2

2

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PLUS Display Unit

Figure 1-2: Basic Echosounder System using the DSM250

The DSM250 module is waterproof to CFR46 and can be installed
either above or below deck.

The unit includes connections to:

• power

• the transducer

• the display unit, via

hsb

2

• ground

D6160-1

Chapter 1: Overview 1-5

Transducer

The DSM250 requires a transducer, mounted either thru-hull, in­hull, or on the transom.

Transducers can measure water depth, and if so equipped, temper­ature, distance traveled, and/or speed. It is important to position
your transducer correctly. For details on transducers, including
location and installation instructions, see document number
81196, Transducers for Fishfinders Owner’s Handbook.

Note: If speed, temperature, or distance travelled are being input to
the display unit via SeaTalk, the SeaTalk value is displayed instead of
the value transmitted by the DSM250.

Sonar Mode Display Features

When connected to a display unit and switched to Sonar mode,
the following data can be viewed:

• Depth, speed, and temperature, if the transducer is so equipped

• Single or split frequency sonar display – 50 kHz, 200 kHz

• Display options – sonar window, zoom, bottom lock, and A­Scope

• Horizontal and vertical half-screen windows to display additional
data. Position data requires GPS.

1.2 Sonar Mode Display

When you first switch the display unit into Sonar mode, the
scrolling bottom graph is displayed. This is a graphical represen­tation of the echoes seen by the DSM250. As time passes, this dis­play scrolls from right to left and becomes a record of the echoes
seen. A typical display is shown in Figure 1-3 .

The images at the right hand side of the display are the most
recent echoes. Some echoes indicate fish, and others show the
bottom. It can also indicate bottom structures, such as a reef or
shipwreck. The upper and lower depth range limits are shown.

The sonar screen includes a status bar that displays transducer fre­quency and indicates which auto settings are enabled (Gain, Color
Gain, Range, Zoom and Frequency), and alarm status (fish and
shallow/deep water depths).

1-6 DSM250 Digital Sounder Module

You can customize the sounder by choosing what is displayed and
how it is displayed (including language and units). For example,
you can set the scroll speed of the bottom graph display, and you
can select the range to adjust the depth displayed.

You can view the cursor position and a variety of data (such as
speed and depth) from the transducer and other equipment in user­selectable data boxes. These data boxes can be moved around the
screen and they can be switched on or off.

Chapter 3 includes details on adjusting the display, other set up
options are described in Section 4.4.

Auto
Mode
Indicators

Power
Frequency
Zoom
Range
Color gain
Gain

Alarm enabled
Shallow, Deep
Fish

Target Depth ID On

Frequency

Alarm
Indicators

Cursor,

controlled
by trackpad

Bottom depth

AUTO GCRZFH

18

50kHz

22

38

36

35

42

SD

33

36

32

37

ft

ZOOMFREQUENCY

BTM.LOCK A-SCOPE

Figure 1-3: Typical Display in Sonar Mode

20

40

Water surface

0

Depth markers

Target image (fish arch)

Target image depth

Range

60

D6181-1

Chapter 1: Overview 1-7

Operating Modes

Depending on the types of display(s) you have connected via
up to four full-screen modes – sonar, chart, radar, and data log are
available. You select the operating mode using the DISPLAY key
as described in Chapter 3.

You can also set Windows On to split the display into two half-
screen windows (horizontal or vertical) to show supplementary
data, or to display sonar and chart or radar simultaneously.

Horizontal Half -Screen Window Options

Using horizontal half screens, the main operating mode is dis­played in the upper window; you choose what is displayed in the
lower window. The following information, if available on your
system, can be shown:

Table 1-1: Horizontal Half-Screen Window Options

Full-screen
mode Horizontal Half-Screen Window Options

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2

,

Sonar Mode Course Deviation Indicator (CDI), Bearing and Distance

Chart Mode CDI, BDI, Navigation Data (databoxes), Radar, Sonar

Radar Mode CDI, BDI, Navigation Data, Chartplotter, Sonar

Data Log Mode Half-screens not available

Indicator (BDI), Depth/Temp graph, Chart plotter, Radar

Vertical Half -Screen Window Options

This option splits the sounder vertically. The left hand window dis­plays data boxes; there are three different sets of data (A, B, and C)
that you can select for display. The following information is avail­able only in Sonar Mode:

Table 1-2: Vertical Half-Screen Window Options

Full-screen
mode

A Temperature, Speed, Depth

B Position (latitude and longitude), Course Over Ground

C Waypoint Range and Bearing, COG, SOG, Depth

Vertical Half-Screen Window Options

(COG), Speed Over Ground (SOG), Depth

1-8 DSM250 Digital Sounder Module

Note: Receiving and displaying position data requires that a GPS is
connected to your Raymarine system.

Horizontal Half-Screen

AUTO GCRZFH

50kHz

ft

XTE

0.28nm

WPT BRG

351°T

WPT RNG

0

20

40

60

Vertical Half-Screen

AUTO GC FH

TEMPERATURE

30 0MINUTES

50kHz

20.1

15.1

10.1

SPEED

DEPTH

F

kts

0

20

40

26.8nm

STEER PORT

WAYPOINT 001

ZOOMFREQUENCY

BTM.LOCK A-SCOPE

03

TTG

h:59m

ft

ZOOMFREQUENCY

BTM.LOCK A-SCOPE

60

60

D6206-1

Figure 1-4: Half-Screen Windows in Sonar Mode

Details on selecting windows are given in Chapter 3.

For details on the radar, chartplotter or fishfinder display, please
refer to the Owner’s Handbook supplied with that unit.

Sonar Options

The DSM250 provides controls to select additional modes:

• Frequency – you can select the transducer frequency: 50 kHz for
wide coverage and deep water, 200 kHz for a detailed view, both
frequencies simultaneously or auto-frequency. The default set­ting is auto-frequency, which determines the optimum frequency
of operation based on the current depth.

• Bottom Lock – changes the operating mode to re-set the bottom.
It provides a bottom-up view: the bottom is used as the reference,
its image is flattened and depths are displayed here.
Bottom lock mode is used primarily to filter out the bottom struc­ture and display fish details only.

• A-Scope – displays a real-time image of the bottom structure and
fish directly below the transducer. The A-Scope window also dis­plays the patented Bottom Coverage width indication.

Chapter 1: Overview 1-9

• Zoom – enlarges all or part of the bottom graph display. You can
select x2, x4, or x6 magnification and the zoom area can be auto­matically or manually adjusted.

You can select the Zoom or Bottom Lock image to be displayed in
place of the regular bottom graph display. Alternatively, you can
set the display window to be split vertically with the bottom graph
displayed in the right hand screen and the Zoom or Bottom Lock
image displayed in the left hand screen. See Figure 1-5 .

If you choose dual frequency, the scrolling bottom graph is dis­played in both frequencies, split horizontally. Zoom, Bottom
Lock, or A-Scope can be displayed with the dual frequency graph.

All of these options are available when the sonar data is displayed
in a half-screen window.

Sounder Functions

The DSM250 includes the following functions:

• Automatic or manual selection of scroll speed for bottom graph
display

• Automatic or manual selection of transducer frequency

• Automatic or manual selection of depth range limits

• Automatic or manual selection of Gain, Color Gain, and STC set­tings

• Set up alarms for Fish, Shallow water and Deep water

• VRM marker to determine depth and distance

Operation of these functions is described in Chapter 3 and
Chapter 6.

1-10 DSM250 Digital Sounder Module

AUTO GC Z H

SPLIT

0

20

AUTO GC Z H

SPLIT

0

20

40

60

200kHz

200kHz

50kHz

50kHz

ft

ZOOMFREQUENCY

Split Frequency Split Frequency with A-Scope

AUTO GC Z H

BTM.LOCK A-SCOPE

200kHz

80

0

20

40

60

80

200kHz

200kHz

50kHz

50kHz

AUTO GC Z H

ft

ZOOMFREQUENCY

SPLIT

0

30

20

20

200kHz

40

10

200kHz

50kHz

40

60

80 6.8

0

20

40

60

80

27.2

27.2

BTM.LOCK A-SCOPE

55

20

40

60

75
55

20

0

80

0

BL

0

ft

ZOOMFREQUENCY

Bottom Lock Split with Bottom Graph Zoom Split with Split Frequency

BTM.LOCK A-SCOPE

60

80

80

X4

ft

ZOOMFREQUENCY

Figure 1-5: Sonar Display Options

40

60

75

BTM.LOCK A-SCOPE

80

D6202-1

Chapter 2: Installation 2-1

Chapter 2: Installation

2.1 Introduction

This chapter provides installation instructions for your DSM250.
Basic systems, such as that in Figure 2-1 below, are explained.
Details for mounting the DSM250 and connecting the equipment
are included.

Transducer

Compass

Digital Sounder Module

hsb

12/24V Supply

2

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PLUS Display Unit

GPS

Junction

SeaTalk

2

Distribution Panel

Box

D6164-1

NMEA

12/24V Supply

12V Supply

12V Supply

Figure 2-1: DSM250 in an Integrated System

Note: If you wish to practice using the unit before installation, con­nect the HSB cable to a PLUS display unit and use the simulator mode
as described in Chapter 3. For power, connect a 12V or 24V DC
power supply, attaching the red wire via a quick blow 8A fuse to pos­itive and the black wire to negative. See Section 3.6 for details.

For the system to display depth, water temperature and speed, you
must install the transducer type(s) capable of transmitting the
appropriate data.

For full functionality of the radar and chartplotter you need to pro­vide position and heading data. For details, refer to the handbooks
for those products.

2-2 DSM250 Digital Sounder Module

Planning the Installation

Before you install your system, plan the installation, considering:

• Correct transducer for your application. See document number
81196, Transducers for Fishfinders Owner’s Handbook.

• Location of the display unit, as described in Section 2.3

• Cable Runs, including cables for an integrated system (to provide
heading and position data, etc.), as described in Section 2.4.

EMC Installation Guidelines

All Raymarine equipment and accessories are designed to the best
industry standards for use in the recreational marine environment.

Their design and manufacture conforms to the appropriate Elec­tromagnetic Compatibility (EMC) standards, but correct installa­tion is required to ensure that performance is not compromised.
Although every effort has been taken to ensure that they will per­form under all conditions, it is important to understand what fac­tors could affect the operation of the product.

The guidelines given here describe the conditions for optimum
EMC performance, but it is recognized that it may not be possible
to meet all of these conditions in all situations. To ensure the best
possible conditions for EMC performance within the constraints
imposed by any location, always ensure the maximum separation
possible between different items of electrical equipment.

For optimum EMC performance, it is recommended that wher-
ever possible:

• Raymarine equipment and cables connected to it are:

• At least 3 ft (1 m) from any equipment transmitting or cables

carrying radio signals, e.g., VHF radios, cables and antennas.
In the case of SSB radios, the distance should be increased to
7ft (2m).

• More than 7 ft (2 m) from the path of a radar beam. A radar

beam can normally be assumed to spread 20 degrees above
and below the radiating element.

• The equipment is supplied from a separate battery from that used
for engine start. Voltage drops below 10 V and starter motor tran­sients can cause the equipment to reset.

Chapter 2: Installation 2-3

This will not damage the equipment, but may cause the loss of
some information and may change the operating mode.

• Raymarine specified cables are used. Cutting and rejoining these
cables can compromise EMC performance and must be avoided
unless doing so is detailed in the installation manual.

• If a suppression ferrite is attached to a cable, this ferrite should not
be removed. If the ferrite needs to be removed during installation
it must be reassembled in the same position.

Suppression Ferrites

The following illustration shows typical cable suppression ferrites
used with Raymarine equipment. Always use the ferrites supplied
by Raymarine.

D3548-3

Figure 2-2: Typical Suppression Ferrites

Connections to Other Equipment

If your Raymarine equipment is to be connected to other equip­ment using a cable not supplied by Raymarine, a suppression fer­rite must always be attached to the cable that is closest to the
Raymarine unit.

2-4 DSM250 Digital Sounder Module

2.2 Unpacking and Inspecting the Components

Unpack your system carefully, to prevent damage to the equip­ment. Save the carton and packing, in case you need to return a
unit for service.

Check that you have all the correct system components. These
depend on your system package, as follows:

Table 2-1: Parts and Accessories

Item Part No. Supplied / Option

DSM250 Digital Sounder Module E62007 supplied

Handbook, DSM250
Handbook, Transducers for Fishfinders
Quick Reference Card, Fishfinder mode

Mounting screws, #8 (x4) N/A supplied

Power cable, 3 pin, 3 m R69053 supplied

2

hsb

cable assy

3 ft 3 in (1 m)
10 ft (3 m)
20 ft (6 m)
30 ft (10 m)
60 ft (20m)

2

hsb

In Line Terminator

2

hsb

Splitter Cable

Transducer and Cables (See

Transducers for Fishfinders Handbook

81196

81211
81196
86066

R55001
R55002
R55003
R55004
E55010
R58117
E55040

— —

)

2.3 Selecting the Equipment Location

Sounder Module Mounting Location

The DSM250 is waterproof to CFR46 is and designed to be
mounted either above or below deck. The unit should be protected
from physical damage and excessive vibration.

WARNING:

Mount the DSM250 in a protected area away from prolonged
exposure to rain, salt spray, and direct sunlight, but well
ventilated. Locate the sounder as close to the transducer as
possible. Raymarine suggests not locating the DSM250 on the
main console.

supplied
supplied
supplied

option
supplied
option
option
option
option
option

Chapter 2: Installation 2-5

CAUTION:

Do not mount the DSM250 in the engine compartment.

When planning the installation, the following should be consid­ered to ensure reliable and trouble free operation:

• Access: There must be sufficient space below the unit to enable
cable connections to the panel connectors, avoiding tight bends in
the cable.

• Interference: The selected location should be far enough away
from devices that may cause interference, such as motors, genera­tors, and radio transmitter/receivers (see the EMC guidelines ear­lier in this section).

• Magnetic compass: Mount the unit at least 3 ft (1m) away from a
magnetic compass.

• Cable runs: The unit must be located near a DC power source.
The power cable supplied is 10 ft (3 m), but a longer cable can be
used if desired. Refer to Section 2.4.

The maximum length of cable between the sounder module and
the transducer unit should not normally exceed 30 ft (10 m). If
you need to use a longer cable, refer to Section 2.4.

• Environment: Good ventilation is required to prevent the unit
from overheating.

2.4 Cable Runs

Consider the following before installing the system cables:

• You will need to attach the power, transducer, and HSB cables.

• All cables should be adequately secured, protected from physical

• Sharp bends must be avoided.

CAUTION:

Removal of the transducer cable from the DSM250 while
power is turned on can cause sparks. As with any electronic
device, be sure the sounder module is mounted where it is well
ventilated and free from gasoline fumes.

Additional cables will be required if you are installing an inte­grated system.

damage, and protected from exposure to heat.
Avoid running cables through bilges or doorways, or close to
moving or hot objects.

2-6 DSM250 Digital Sounder Module

• Where a cable passes through an exposed bulkhead or deckhead,
a watertight feed-through should be used.

• Secure cables in place using tie-wraps or lacing twine. Coil any
extra cable and tie it out of the way.

You will need to run the following cables:

• Power cable, supplied with the unit. This 10 ft (3 m) cable has a
connector plug at one end for connecting to the sounder module,
and 3 wires at the other end for connecting the power supply. The
power cable may be extended by up to 60 ft (20 m) using a wire
gauge of AWG 12 or greater. The DSM250 is intended for use
on ships’ DC power systems rated from 10.7 V to 32 V.

• HSB cable, supplied with the unit. This 10 ft (3m) cable is used to
connect the DSM250 to the display unit. Other lengths of HSB
cables are available from Raymarine. See Table 2-1 Parts and
Accessories on page 2-4.

• Transducer cab le, supplied with the transducer. This 30 ft (10 m)
cable has a connector plug (with an outer nut that you must attach)
at one end for the display unit or extension cable. The transducer
cable may be extended up to a maximum of 60 ft (20 m) using
optional extension cables. For details, see document number
81196, Transducers for Fishfinders Owner’s Handbook.

WARNING:

Do not cut the transducer cable or remove the connector.
Do not try to shorten or splice the cable. Cutting the
transducer cable will severely reduce sonar performance.
If the cable is cut, it must be replaced—it cannot be repaired.
Cutting the cable will also void the warranty.

Chapter 2: Installation 2-7

1.65 in
(41.8 mm)

3.46 in

(88 mm)

Weight: 2.2 lbs (1.0 Kg)

9.96 in (252.9 mm)

9.51 in (241.6 mm)

10.76 in (273.3 mm)

Figure 2-3: DSM250 Unit Dimensions

Compass Safe Distance: 39 in (1 m)

D6168-1

7.37 in (187.2 mm)

2.43 in
(61.7 mm)

2-8 DSM250 Digital Sounder Module

2.5 Mounting the Sounder Module

The DSM250 can be installed either above or below deck using
the supplied hardware.

CAUTION:

Do not mount the DSM250 in the engine compartment.

To allow for proper water drainage and ease of cable connection,
the DMS250 should be mounted vertically, so that the cables can
hang below the unit, as in Figure 2-4 .

To mount the DSM250:

1. Hold the module in the location where you want to mount it, mak­ing sure the unit is perpendicular to the floor, as in Figure 2-4 .

2. With a pencil, mark the tops (narrow ends) of the four key holes
onto the mounting surface. Set aside the module.

3. Drill a 9/64" pilot hole at each of the four marked locations.

Note: For fiberglass with a gelcoat surface, you should overdrill
the surface to prevent the gelcoat from chipping when driving in
the screw. Before drilling the pilot hole, hand drill the marked lo­cation with an oversized bit and countersink to approximately
3/8" diameter.

4. Drive the supplied #8 screws into the pilot holes. Screw them in
about half way.

5. Mount the module to the surface, slipping the screw heads
through the four key holes.

6. Press the module downward so the screws align with the narrow
end of the keyholes.

7. Tighten the screws. Do not overtighten.

Chapter 2: Installation 2-9

D6183-1

Figure 2-4: Mounting the DSM250

2.6 System Connections

The rear of the display unit provides the following connection
sockets:

• Transducer connection.

• Ground connection.

• Power, for 12 V, 24 V, or 32 V DC power connection and one RF

ground (screen) connection.

• HSB, in/out connector for connecting to an

play (Chartplotter, Fishfinder or Pathfinder Radar)

2

hsb

PLUS Series dis-

D6161-1

Figure 2-5: DSM250 Connector Panel

The following sections detail the connectors used when installing
the DSM250.

2-10 DSM250 Digital Sounder Module

DC Power Connection

The DSM250 is intended for use on ships’ DC power systems
rated from 10.7 V to 32 V.

The power connection to the unit should be made at either the out­put of the battery isolator switch, or at a DC power distribution
panel. Raymarine recommends that power is fed directly to the
DSM250 via its own dedicated cable system and MUST be pro­tected by a thermal circuit breaker or fuse on the red (positive)
wire, installed close to the power connection.

A 10 ft (3 m) power cable is supplied for connecting the ship’s DC
power to the unit. The power cable may be extended by up to 60 ft
(20 m) using a wire gauge of AWG 12 or greater.

DC power is connected at the three-pin POWER connector on the
unit’s connector panel. The connector (viewed from the outside)
and pin functions are shown in the following diagram and table.

f

1

2

3

D6162-1

Figure 2-6: Power Connector

Pin No. Function Color

1 Battery positive (12/24/32 V systems) Red

2 Battery negative Black

3 Shield (drain wire) No insulation

The RED wire must be connected to the feed from the positive (+)
battery terminal and the BLACK wire to the feed from the nega­tive (–) battery terminal. The shield wire (drain) should be con­nected to the ship’s RF ground as described in Ground
Connection on page 2-11.

Install a quick blow 8 amp fuse on the red (positive) wire.