SVP70_71_Manual102b(s).pdf

SVP-7x Operators Manual rev.1.02/2006 1 Page

OPERATOR’S MANUAL

SVP 70

SVP 71

Direct Reading

Sound Velocity Probes

Document Number 904-63-0802-00

Firmware Version: 060614164653

SVP-7x Operators Manual rev.1.02/2006 2 Page

Notice The information contained in this document is subject to change without notice. RESON makes no warranty of any kind with regard to this material, including (but not limited to) the implied warranties of merchant liability and fitness for a particular purpose. RESON shall not be liable for errors contained herein or for incidental or consequential damages in con-nection with the furnishing, performance, or use of this material.

Copyright Statement

Copyright RESON AS. 2003. All rights re-served. Reproduction, adaptation or transla-tion without prior written permission is prohibited, as per the copyright laws of the United States.

Copyright Release

No part of this technical manual may be cop-ied or distributed, transmitted, transcribed, stored in a retrieval system or translated into any human or machine readable language, in any form or by any means for disclosure to third parties without the express written con-sent of RESON.

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Printing History

RESON strives to maintain up-to-date infor-mation and may, as necessary, review and revise this manual. If the information con-tained in this manual is unclear, please con-tact your nearest RESON office for clarification.

Electronic File Version

This manual is available from RESON in the Adobe® Acrobat® Portable Document For-mat (PDF). The selected PDF process pre-serves the interactive index and cross-reference features of the original Microsoft Word document.

Warranty The SVP Series warranty is only valid on a complete SVP. The warranty will be void if any modification is done to the SVP or in case it has been disassembled.

References References to 3.rd party companies are given without any liability of RESON. The refer-ences are given only as hints.

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TABLE OF CONTENTS

1 INTRODUCTION

1.1 Getting Started

1.1.1 Unpack the SVP-7x

1.1.2 Set up a PC and a power supply

1.1.3 Connect the units

1.1.4 Start the PC program

1.1.5 Starting the probe

1.1.6 Changing appearance of the SVP data

1.1.7 Changing communications parameters

(Comport and baud rate)

2 OPERATING PROCEDURES

2.1 Configuration mode

2.1.1 How to enter configuration mode

2.2 Mode 2 AML output

2.3 Mode 3 Valeport output

2.4 Mode 4 RESON output

2.5 Mode 5 SVP 7x MODE

2.5.1 User menu

2.5.2 Output configuration

2.6 Mode 6 NMEA Output Mode

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3 SVP PRINCIPLES

3.1 Application notes for SVP’s

3.1.1 Multi beam correction

3.1.2 Echo sounder correction

3.1.3 Positioning system correction

4 INSTALLATION

4.1 Introduction

4.2 Mechanical installation

4.2.1 Mechanical installation SVP 71

4.2.2 SVP 71 Anode service

4.2.3 Placement of the SVP 7x

4.2.4 Cable installation

4.3 Electrical Installation

4.3.1 Power source

4.3.2 Serial interface

4.3.3 Connector SVP 70

4.3.4 Standard test cable (SVP70 ONLY)

4.3.5 Connector SVP 71

4.3.6 Test cable for SVP 71

4.3.7 Recommended High grade RS422 cable .53

4.3.8 Recommended RS232 cable

APPENDIX A CONTACT INFORMATION55

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APPENDIX B TECHNICAL SPEC

APPENDIX C DATA FORMATS

APPENDIX D INSTALLATION

APPENDIX E DRILL FOR BRACKET

APPENDIX F SVP 70 TEST CABLE

SVP70

APPENDIX G SVP 71 TEST CABLE

APPENDIX G

APPENDIX H SVP 70 DIMENSIONS

APPENDIX I SVP 71 DIMENSIONS

APPENDIX J TYPICAL ERRORS

APPENDIX K ACCESSORIES

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1 INTRODUCTION

This manual covers the SVP-7x Series sound velocity probes, which consists of the following product range:

• SVP 70

• SVP 71

SVP70 SVP71

Housing Titanium Hard anodized, sea water resis-tant ALU

Pressure rating 6000m 2000m communications RS232 and

RS422

RS232

Connector MCIL9M MCIL6M Weight 1000g 650g SVP 7x series comparison

The SVP-7x probes are direct reading sound velocity probes for professional applications. They employ state of the art correlation techniques in a FPGA implementation for finding the time of flight of sound in the medium with the highest accuracy.

The probe has a very compact design without sacrificing the length of the signal path, which is of utmost impor-tance in returning accurate results. On an overall length of 160mm the sound transmission path is 125mm.

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The novel design of the SVP allows for simpler integration with less disturbances of the water flow, yielding a low emission of noise into nearby sensors like echosounder, sonar systems, Doppler logs etc. Ping synchronization allows for low integration risk.

SVP 70: The robust Titanium design eases cleaning in environments with high levels of marine growth, which is specifically relevant for permanent installations.

SVP71: It's hard anodized sea water resistant aluminum housing saves weight and is recommended for semi-permanent mounting such as those used for outboard rigs or AUV's/ ROV's where regular maintenance is possible.

The electrical interface includes wide input power (9 to 55V, approx 2W) and dual serial interfaces according to RS232 and RS4221 (full standard voltage swings, >500m range). There is no galvanic connection between the power input and the serial output.

Measurements can either run at a user specified sam-pling frequency or can be synchronized to an external trigger to ensure no acoustic interference problems, which would otherwise be present.

Selectable processing includes outlier removal and low pass filtering, for use when the unfiltered measurements with mm/s RMS noise are not adequate.

SVP71 only has RS232

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1.1 Getting Started

Thank you for buying a SVP 7x series sound velocity probe.

For exhaustive guidance on installation, configuration and settings refer to succeeding sections.

But first, the best way to get familiar with your new SVP- 7x is to unpack it in the office and connect it to a PC; then deploying it in a bucket of water and get readings into the PC. To do this the following steps are required:

1.1.1 Unpack the SVP-7x

Unpack the SVP-7x and make sure all accessories marked on the packaging list are present.

1.1.2 Set up a PC and a power supply

In addition to these items you will need a PC with a nor-mal serial port connector (Sub-D 9 pin male) and if not included in the delivery, a power supply or a fully charged 12 or 24 V lead-acid battery.

1.1.3 Connect the units

Connect the SVP-7x to the rubber connector in one end of the test cable. The Rubber Connector is slightly

SVP-7x Operators Manual rev.1.02/2006 10 Page greased to lower the insertion force. Don’t pull on the ca-ble.

SVP70: Connect the Serial port (also called COM port) of the PC to the BLACK 9 pin female connector on the test cable.

Connect the black wire of the test cable to the negative power supply terminal.

For a while leave the red wire unconnected.

Put the probe into a bucket of water.

SVP71: fit a DB9 female connector to the pigtail delivered with the SVP and connect it to the PC's serial port. Con-nect the power wires to the energy source.

Connections on SVP71 test cable

Signal name pigtail wire color

Recommendation (not mounted from factory) DB9 pin nr

COMMS GND Black 5 RS232 TX Green 2 RS232 Rx Brown 3 Power (9-

55VDC)

Blue Battery +

Not connected Yellow Ground Blue/Brown Battery-

These colors are only valid for the cable supplied by Reson.

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1.1.4 Start the PC program

Users familiar with serial communications may prefer to use another program instead of HyperTerminal.2

On the PC start the program “HyperTerminal” which you find in the start menu under START->PROGRAMS- >Accessories->Communications->Hyperterm.

Enter a name (SVP70 or SVP71) and press OK.

Make sure to disable handshake control (use neither Hardware, nor software handshake)

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In the next dialog choose “connect using” and then the COMPORT that is connected to the connector you at-tached the cable to. This is Typically COM1 or COM2 on PCs.

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Configure the serial port as shown above and press OK

1.1.5 Starting the probe

Now connect the red wire to the positive power supply terminal and switch it on (in the case that it is not a bat-tery).

You will now see data from the SVP on the screen.

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You can save these data to a file using the tool menu. (Or for now just let them scroll across the screen).

NOTE

In the case that no sound velocity data appears on the screen, try another port.

In case odd characters appear on the screen, try different baud rate settings in HyperTerminal.

In case sound speed readings show 1350m/s it is likely that air bubbles are trapped on the black transducer sur-face. Wipe it with a finger.

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1.1.6 Changing appearance of the SVP data

Pressing “M” will bring up a menu, which allow configura-tion of the output format.

Selecting an item in the menu will either output further help text with an input prompt or change the setting shown in the User Menu.

Typing “E” saves all changes and exits the User Menu.

Typing “e” discards all changes and exits the User Menu.

Refer to section 2 for a full explanation of the User menu system.

1.1.7 Changing communications parameters

(Comport and baud rate)

On startup the probe will listen for 5 seconds for the con-figuration command. During this time it is possible to en-ter the configuration menu by typing the 4 characters

“CON;”

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The probe will respond by entering the config mode and providing the config menu shown below.

SVP71 Alive Firmware: 20060614164653 PCBSer#: BBA6F428-1A000000 HousingSer#: BAC74628-20000000 Waiting for cfg command(@9600)...............x

*CONFIG*

E Save e Don't Save B Boot a ShowAliveMsg: 1 o OpMode: 5 c ComRxDisable: 0 b Baud Rate 9600 s SerChan 0 u UserMenuCmdChar: M t PingOnceTriggerCmd: T

This menu is only available on RS232 at 9600,n,8,1

In this menu one is able to change the hardware setup of the probe. Changes to this menu only take effect after the “Save” option is selected by typing “E”.

If you want to discard changes made in this menu then type “e” to discard all changes.

To change the com port from RS232 to RS422 type “s”.

The menu item “s” will change to “1”.

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0 means use RS232 for User mode comms 1 means use RS422 for User mode comms3

To change the comms baud rate for User Mode type “b”.

A prompt will appear showing the allowable range

Enter Baud Rate: in range[ 110:115200] Current Setting: 9600

Select a setting and push enter. You will see that the baud setting has changed in the menu.

REMEMBER: The setting you have changed will only take effect once the option “E” is selected. Once this is done the text “Config saved” will be output and the config menu will be echoed with the new setting.

To get out of the config mode one must restart the probe.

Approximately 5 seconds after startup the user mode will automatically be entered.

NOTE

You will always be able to get in contact with the probe on startup on RS232 at 9600,n,8,1

The SVP71 does not support RS422 output, and will therefore not output data if put in serial mode 1

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2 OPERATING PROCEDURES

The probe has two main modes:

Configuration mode and user mode.

Configuration can be entered just after power on and is normally exited after saving parameters.

User mode is entered upon startup if the special config key strokes are not entered within a few seconds after power up.

There are no key strokes that allow switching between these modes later.

The user mode has additional settings that can be edited by pressing “M” which stops acquisition and enters the User Mode menu.

2.1 Configuration mode

2.1.1 How to enter configuration mode

SVP71 does not support RS422. Configuring SVP71 for RS422 re-sults in no output.

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No special software is needed, but CRT from www.vandyke.com is a good alternative to Windows Hy-perterm for control and logging. Connect the probe, Start your terminal program (e.g. HyperTerminal)

The probe starts optionally transmitting a sign on mes-sage and then listens at RS232 9600,n,8,1. To enter con-figuration mode press the 4 keys ”CON;”

If these keys are not sent to the probe within 5 seconds, it automatically resumes its previous operation mode, which may use another port/ baud-rate for input/output!

To start the operations mode directly after startup without waiting push the keyboard ‘ESCAPE’ key.

The config mode menu is shown below:

*CONFIG*

E Save e Don't Save B Boot a ShowAliveMsg: 1 o OpMode: 5 c ComRxDisable: 0 b Baud Rate 9600 s SerChan 0 u UserMenuCmdChar: M t PingOnceTriggerCmd: T

Configuration items To change these options, enter the configuration menu as described above. Changes made will only take effect once they have been saved with the command “E”.

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To discard all changes use the command “e”.

Re-boot Probe (Boot) Press “B” to reboot the probe. This has the same result as restarting the probe by turning the power supply off and on again. This option is intended to help configuration of the probe before its first use.

Sign on message (ShowAliveMsg) Press “a” to turn the probe sign on message on or off.

The sign on message is displayed after power up and helps identify the probe and validate a proper connection to the software.

In case the probe is used with survey software that doesn’t accepts the sign on message, which is somewhat out of format, turn the sign on message off. “0” means sign on message not shown.

Operations Mode (OpMode) This option selects the Operations Mode that will be run automatically on startup. By typing the command charac-ter “o” the value for OpMode in the menu can be toggled.

The following OpModes exist:

0. The configuration mode.

1. The configuration mode (same as 1).

2. Emulates AML Smart Probe output format.

3. Emulates Valeport Probe standard output format.

4. Emulates old RESON standard output format.

(SVP-24/SVP-C)

5. SVP-70 mode.

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6. NMEA output format

The OpModes are all described in detail further on in this Chapter.

Comport Receive Disable (ComRxDisable) This will totally disable all software handling of the Rx part of the serial communication. This is useful in setups where the probe is connected to a communication chan-nel with lots of irrelevant data on it, which causes some instruments to break. The serial channel Rx can be re-enabled by cycling power off and back on, or sending the special command sequence “wakeup314159265” to the probe.

Baud rate To change the comms baud rate for User Mode type “b”.

A prompt will appear showing the allowable range

Select a setting and push <enter>. You will see that the baud setting has changed in the menu. Just push <en-ter> if you want to keep the old setting.

If you select a setting that is too big or too small the value will be set to the respective maximum or minimum value and some warning text will be shown.

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The comport can be set to any value in the range 110 to 115200, even ‘non-standard’ values. If you make a mis-take and enter a value that you later forget then you can always get into contact with the probe during startup on baud 9600 on the RS232 port.

Serial port (RS232 or RS422) To change the serial channel used for User Mode select the option “s”. The value will toggle in the menu.

“0” means that RS232 will be used.

“1” means that RS422 will be used4.

Select Character that activates Menu (UserMenuCmdChar) This is the configurable command character that is used to enter the User menu in the User mode.

Select Character that Triggers a Measurement (PingOnceTriggerCmd) This is the configurable character that is used to make one reading when the probe is in the externally triggered mode, i.e. when Sample Period is set to zero in the User Menu.

Not available on SVP71

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2.2 Mode 2 AML output

In AML output mode, the probe outputs data in the format

<SPACE>SOS in m/s with 2 decimals<SPACE><CR><LF>

Example:

1543.39

The probe doesn’t respond to any commands, and has a fixed output repetition rate of 10Hz.

2.3 Mode 3 Valeport output

In Valeport output mode, the probe outputs data in the format

<SPACE><SOS in millimeters><CR><LF>

Example:

1543390

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2.4 Mode 4 RESON output

In Reson mode output mode, the probe outputs data in the format used by the SVP-24 and the SVP-C.

<SOS><Pressure><Temperature><Bat Volt-age><Memory Count>

Pressure depth in deci-bars.

Temperature in Celsius, with one decimal.

Battery voltage = 10V always

Memory Count = 1010 always

Example :

0343300000277101010

2.5 Mode 5 SVP 7x MODE

Starting the SVP 7x in mode 5 gives detailed control of all operation parameters.

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2.5.1 User menu

When the probe is running it is possible to enter the User menu by pressing “M”. The following menu will be shown.

Note: The character “M” is configurable in the Configura-tion mode.

**SIMPLE MENU**

M Menu E Save and Exit e Exit no saving b Baud Rate 9600 H Header:$SVP T Tail:;

D Delimiter:

W Data width: 3 S SOS digits 3 F Filter 0 I Time 0 r RawData 0 s Sample Period 1000 --Print flags:--p Pres 1 t Temp 1 a Amp 1 n Noise 1 f Print Filter 1 v DataValid 1 d All delims 1

The options in this menu control the output configuration of the probe in User mode. All changes made will be dis-played in the menu. Changes only take effect once the menu is exited.

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To change one of the fields type its preceding command character and enter the new settings.

Type “E” to save all changes and exit the menu.

Type “e” to discard all changes and exit the menu.

2.5.2 Output configuration

$PSOS 123234,1450.002,20.3,102.5,210,9,0,1<CR><LF>

Header (any string up to 7 characters) Here: $PSOS<space>

Use \n to enter <LF> \t to enter TAB \r to enter CR \0 to enter no character

*Pressure in Decibar

*Probe temperature in Celcius

Delimiters. Any character or none

Number of decimals from 0 to 4

Sound velocity in m/s

Tail (Any string up to 5 characters)

"*" designates optional outputs

*Time in one of 2 formats. s (as float),ms (as integer)

Signal Amplitude (bits)

Approx. Signal Noise (bits)

Filter type (0-2)

Validity of last sample (Valid if 1, Invalid if 0)

The output has the form shown above.

By turning on and off the various fields it is possible to construct almost any desirable output format.

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NOTE:.

It is not possible to change the order of the fields

Special character entry The user may want to enter characters that are normally confused with control characters. To enter these special characters do as follows (Users familiar with the C pro-gramming language will find this familiar):

To enter Press meaning Character

(ASCII Deci-mal)

<CR> \r The carriage re-turn character, <LF> \n New line <TAB> \t or

<TAB>

key

Tabulator key

<SPACE> <SPACE>

key

Space character

NUL It is not possible to use the 0 character

#00

Special characters \r and \n display “as they are” in the menu and thus may distort the menu display slightly.

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Header <H> The header is a combination of any 7 characters, exclud-ing the null character.

Press the character sequence and press <ENTER> to terminate.

The header is printed in the menu exactly as it is entered.

The appearance in the menu will be “confusing” if <CR> is used, as it will overwrite previous key-strokes.

Examples of headers are “something”

“$PSVP,”

“$PSVP <TAB>

Tail <T> The tail is entered as the header. Make sure that the use of <CR> and <LF> is accordance with the receiving pro-gram. Some programs convert, skip or insert extra <CR> and <LF> characters, which lead to wrong appearance.

The tail may include the <TAB> character.

TimeStamp <I> The Timestamp is optional. It is a millisecond counter, which starts counting when the probe is started.

The output options are:

1. Don’t print time stamp

2. Seconds with 3 digits

3. Milliseconds (without decimals)

The command “O” will toggle through the valid time op-tions.

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Sound Velocity decimals <S> The number of decimals to show in the sound velocity measurement reading. May range from 0 to 3. The deci-mal separator is always a decimal point (not a comma).

No decimal point is shown when 0 digits are printed.

Delimiter <D> The delimiter is inserted between all the fields in the out-put string, except after the header (just include the same delimiter as part of the header if required) and except in front of the tail. For easiest pasting into excel use the <TAB> character as delimiter.

Temperature <t> The probe can output its own temperature in Celsius with 2 digits. The temperature corresponds to the water tem-perature, only it is very slowly varying due to the thermal capacity of the housing.

The temperature output is NOT intended as a survey pa-rameter due to its low pass filtered and delayed readings.

The character “t” toggles the temperature from on (1) to off (0).

Pressure <p> The probe can output pressure decibar (corresponds to approximate depth in meters). The pressure reading is very inaccurate and should only be used for guidance.

Amplitude <a> Toggles the output of the amplitude of the return signal.

Noise <n>

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Toggles the noise output on or off.

(Noise estimate is not yet implemented)

Filter <f> and Print Filter <F> There are a number of filters available to filter the speed of sounds output. The type of filter used is controlled by the command “F” which toggles through the available val-ues in the menu.

0. No filtering. (Direct output)

1. Low pass filtering with approximately 5 second time constant)

2. Median filtering (5 taps, removing up to 2 consecutive false readings)

3. Combined Median and Low pass (not yet imple-mented).

The command “f” controls whether the type of filter used is output. “0” means no output. It is important to realize that filtering (both low pass and median) introduces an inherent delay in the data. To avoid data being too old, the filters are turned off if the time between samples is larger than 800ms. This can be verified by printing the fil-ter type used in the output string.

Sample Period <s> On the command “s” the following prompt will appear.

Enter Sample Period(ms): in range[ 0:100000] Current Setting: 100

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The value in milliseconds is the time between successive samples. Remember to increase the baud rate of the communications interface when outputting data at high rates.

All Delimiters <d> If this option is enabled then all delimiters will be printed even if this means that some of the output fields will be empty.

DataValid <v> Gives the status of the current output sample. If it is ‘1’ it means that the sample was valid data in the defined speed of sound interval. This is useful when using filter-ing, to establish the number of samples that are out of the allowed range.

Data Width <W> Controls the minimum width of all data fields output.

Speed of sound, Temperature, Pressure, Signal Ampli-tude, Noise.

Default value is 3.

Baud rate <b> To change the communications baud rate for User Mode type “b”. A prompt will appear showing the allowable range

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Select a setting and push <enter>. You will see that the baud setting has changed in the menu. Just push <en-ter> if you want to keep the old setting.

If you select a setting that is too big or too small the value will be set to the respective maximum or minimum value and some warning text will be shown.

Raw Data <r> This option toggles the output of the raw data samples used to calculate the speed of sound. This option should only be used for debugging an installation. A high baud rate will be required, due to the fact that a lot of data is output. The raw data is output behind the Tail of the out-put string and is always <TAB> delimited.

2.6 Mode 6 NMEA Output Mode

In the NMEA output mode, the probe outputs data in the format

<$PRSOS><SOS in m/s with 3 decimals><*78>

Example:

$PRSOS,1350.000*78

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3 SVP PRINCIPLES

The SVP-70 measures the sound speed in a direct measurement by transmitting a sound pulse and detect-ing its time to travel a well defined path length.

The transmitted signal is generated using arbitrary wave-form techniques to yield optimal conditions for timing the arrival of the returning signal, which is digitized at high frequency and high resolution. The timing is established using a high stability clock oscillator.

The path length is defined by the distance from the transmit transducer to a reflector plate and back again to the transducer, which then acts as a receiver.

The traditional way of establishing a known path length is to use spacers made from INVAR alloy, which doesn’t expand with temperature. However INVAR is not resistant to corrosion and endurance is limited though its life can be prolonged.

The SVP-7x uses Titanium/Aluminium for the spacers, and compensates its temperature and pressure sensitivity by measuring its temperature and stress and applying calibrated factors for the small path length changes.

The use of titanium for the SVP70 model limits corrosion as much as possible.

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Due to the direct measurement of the delay the medium the speed of sound will in no way depend on formulas as-suming a certain relationship between conductivity, salin-ity, temperature, pressure and purity.

The Speed of sound output is selectable between instant direct readings, outlier filtered readings, and low pass fil-tered.

Instant, direct readings will immediately show any change in sound velocity due to air-bubbles, objects and marine life. Whereas some applications use this information other applications are only using the SOS probe to estimate SOS some distance from the probe. The filtered output options are provided for such applications.

SVP-7x outputs The primary output of the SVP 7x is the instant speed of sound. To measure the sound speed the SVP 7x inter-nally measures the temperature of the probe and the pressure. These two measurements can also be output from the probe and give indicative values for temperature and pressure.

These values are not meant to satisfy regular survey re-quirements for pressure (depth) and temperature.

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3.1 Application notes for SVP’s

3.1.1 Multi beam correction

Multi beam sonar's also frequently need speed of sound input for positioning the beams (beam steering). The sound speed accuracy required for multi beam sonar cor-rection is typically in the order of 0.25 m/s to 0.5 m/s.

3.1.2 Echo sounder correction

Sound velocity probes are used for calibration/correction of echo sounders.

As echo sounders measure the time for a signal to propagate to the sea bed and back, and thereby output the distance to the seabed, it is necessary to know the speed of sound in the water.

Sound travel Distance=2*Depth= Echo time* sound speed

As speed of sound depends strongly on salinity, tempera-ture and pressure it is of paramount importance not just to use some standard value for sound velocity in the for-mula. Therefore most echo-sounders allow input of sound velocity, either by electrical connections or via keyboard entry.

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3.1.3 Positioning system correction

Acoustic Navigation systems like LBL and USBL systems use travel time of acoustic signals to determine the dis-tance between acoustic transducers.

For very accurate LBL and USBL navigation the systems typically use sophisticated (Kalman) filters for improve-ment of the accuracy. Adequate accuracy of the sound velocity used in these systems is typically 0.25m/s.

Doppler logs use the speed of sound for back-calculating the sensor speed. Accurate sound speed is mandatory for obtaining accurate sensor speed.

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4 INSTALLATION

4.1 Introduction

Installation of the SVP is very flexible. It must focus on ensuring that the water flows without excessive turbu-lence and away from any air bubbles that may be caught by vessel movement.

ATTENTION!

When mounting the SVP71 (Aluminium housing) make sure it is not touching any metal parts. See separate in-structions below.

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4.2 Mechanical installation

The sound path is shown below. The measurement qual-ity relies on this sound path being completely free from obstacles like mounting harness, cables and other items, and it must be completely submerged in water without air bubbles.

While one must observe that the flow of water to this sound path is free, it is still possible to put protection or hydrodynamic fairings around the probe as long as the sound path is not disturbed.

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4.2.1 Fixing the bolts before mounting

To aid installation 4 o-rings have been supplied in the ac-cessory kit that can be used as retention rings for the mounting bolts.

This will stop the bolts from falling of the brackets when the SVP is mounted underwater; thus making installation by divers more easy.

Fig. Mounting bolts retained by O-rings before mounting takes place.

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4.2.2 Mechanical installation SVP 71

The SVP 71 must be mounted without metal contact.

An insulator plate is delivered with the unit for mounting as shown in the figure below.

Fig. PVC mounting plate ensures that there is no contact between the anodized housing and the mounting frame.

The mounting brackets are fitted with rubber sleeves to isolate them from the probe housing.

SVP-7x Operators Manual rev.1.02/2006 41 Page

4.2.3 SVP 71 Anode service

The SVP 71 is equipped with a zinc anode to protect it from corrosion.

Before deploying the SVP the anode must be checked and brushed with a steel brush. If less than 1/3 of the an-ode is left, it must be replaced.

The thread is M6. Make sure that the thread is clean and the anode is not coated with oil, paint or other films before installing it.

ATTENTION!

Don’t apply force on the end caps defining the length of the sound path.

ATTENTION!

Use brackets less than 2mm thickness and keep any suspension gear out side the acoustic path (see fig)

The SVP7x should be mounted using the two brackets /metal bands supplied with the unit or similar shaped bands.

Example mounting on a pole.

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SVP-7x Operators Manual rev.1.02/2006 43 Page

4.2.4 Placement of the SVP 7x

Hydro dynamics and flow must be taken into account when placing the SVP 7x.

The water flow should be perpendicular to the sound path to give the optimum performance.

The water should not come from the “back” of the hous-ing.

See the figure below.

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4.2.5 Cable installation

ATTENTION!

• Hold the cable in a fixed position with a maximum of 4 cm free spans between support points.

• Keep the bending diameter above 15 cm (6”) at any place in fixed installations.

• When repeated mounting/dismounting is foreseeable, keep the bending diameter above 30cm (12”)

• Never pull the cable. Pull the connector straight apart from the probe when dismounting it. Lubricate the connector to decrease the required mating force.

4.3 Electrical Installation

4.3.1 Power source

The requirements for the power source for the SVP-70 are relaxed. The power input is compatible with DC power supplies ranging from 9V to 55V rated for 2W or more.

It has been specifically designed for compatibility with standard power supplies of 24V and 48V +/-10% and lead acid batteries on nominal 12V, 24V and 48V. A fully charged 48V lead acid battery has a voltage of 54V.

SVP-7x Operators Manual rev.1.02/2006 45 Page

While charging a 48V lead acid battery its voltage can easily reach 58V, which is beyond the DC input specifica-tion of the SVP. Using a 10V, 1W zener diode in series with the positive supply line will allow operation from a 48V battery in both charging and dis-charging conditions.

NOTE

The SVP 7x has under voltage power detection, which disables the probe if the input voltage is inadequate.

However, leaving the probe at voltages in the range 6 to 9V for extended periods may cause permanent damage to the device

4.3.2 Serial interface

The SVP-70 is as standard fitted with two serial inter-faces, RS232 and RS422. Only one interface can be ac-tive at a time. Certain configuration options (including changing baud rate and serial interface) can only be ac-cessed via the RS232 interface. None of these options need to be changed when the probe is installed and shouldn’t influence the users’ selection of interface in the installation.

SVP-7x Operators Manual rev.1.02/2006 46 Page

The RS232 is based on the MAX232ECSE IC, which generates true RS232 signals with voltage swings and rise time limitations according to the RS232 specification.

The RS422 is based on the MAX3084ECSA IC, which generates true RS422 signals with voltage swings and rise time limitations according to the RS422 specification.

The SVP-70 has a built in 100 ohm termination resistor on its RS422 input. Equipment connected to the RS422 interface should also include a termination resistor across RXA and RXB.

Both serial interfaces are isolated from the probe power input. This prevents otherwise frequent problems with ground loops, common impedances, and it allow it to be installed in systems with a power design prohibiting con-nection between analog (or signal) ground and power ground.

To avoid excessive voltages between these two ground systems, a surge protector connects these with a high impedance at voltages up to 50V. Hence the voltage dif-ference between the ground systems must NOT exceed this voltage.

Choosing the right interface The following guide lines should be seen as an introduc-tion to the subject of selecting between RS232 and RS422. Several web sites discuss the subject and suppli-ers like B&B electronics (www.bbelectronics.com) can supply devices for these interfaces along with advice on the subject.

SVP-7x Operators Manual rev.1.02/2006 47 Page

The numbers in the table are shown for guidance. Actual values depend on numerous factors.

Speed vs. cable length

5m 500m noise immunity cost complexity

RS232 115200 2400 bad low low RS4225 115200 115200 excellent higher higher

For laboratory use and for setting up the probe, where only a few meters of cable is required, it is recommended to use RS232 because it allows interface to most regular PC’s without adding any extra hardware.

For use on larger ships it is recommended to use the RS422 as it allows for longer cables and for better noise immunity.

Once the system is set up and the cable installed, we recommend testing the baud rate one step higher than anticipated for normal operation is used for testing that the performance has some margin.

Additional hints Some suppliers sell converters for interfacing RS232 to the USB ports of PC’s. Whereas some of these devices work in some circumstances, it is not recommended to use these devices without ensuring that they actually work in the application. Check both the transmit function AND the receive function.

RS422 is not available on the SVP 71

SVP-7x Operators Manual rev.1.02/2006 48 Page

Professional converters between Ethernet and RS232 or RS422 exists (www.nationalinstruments.com) and work with the SVP-70. However connection to an Ethernet which is used for other signals than the SVP may cause significant delays which ruin the overall performance of the system because of uncontrolled transmission delays.

Networks used for backups, servers and printers are es-pecially prone to large delays.

The RS422 doesn’t work if the A and B lines on either transmission or reception are crossed. It is a prerequisite for operation that TX-A is connected to RX-A and TX-B is connected to RX-B.

Wiring of RS232 is often done casually without proper care not accidentally swapping TX and RX.

To identify an RS232 transmitter observe a negative volt-age (more than 3V) to signal ground on the pin. The re-ceiver typically has a voltage less than 0.5V.

SVP-7x Operators Manual rev.1.02/2006 49 Page

4.3.3 Connector SVP 70

SVP70 connections Signal name SVP 9 pole Pin nr.

Comms. Gnd. 1

RS232T 2

RS232R 3

RS422TXP 4

RS422TXN 5

RS422RXP 6

RS422RXN 7

Ground (battery -) 8 POWER (Battery +) 9

The connector is manufactured by Birns (www.birns.com / www.aquamate.biz ).

Use mating connector: Birns-MC-IL09F.

The mating connector is available as a pigtail from RESON and from Birns with various cable length options.

The pigtail is shielded, the shield being connected to pin 1 (Comms Gnd)

The connector can be submerged in (clean) sea water without being mated, and it is designed to allow mating under water.

Protective caps must be used if the probe is submerged for extended periods without a cable attached.

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4.3.4 Standard test cable (SVP70 ONLY)

Use this cable for setting up the SVP 70, debugging in-stallations and small tasks.

Only one of the computer-connectors can be used at a time (restricted by the SVP 70). Both can, however be connected at the same time.

The standard test cable consists of 1.5m PVC cable spliced onto 1.5m Neoprene cable which is molded di-rectly to a wet mate connector.

Black hooded Sub-D (DB9) Female connector RS232 Signal name

Pin nr.

Not connected 1

RS232T 2

RS232R 3

Not connected 4

COMMS GND 5

Not connected 6 Not connected 7 Not connected 8 Not connected 9

SVP-7x Operators Manual rev.1.02/2006 51 Page

RED hooded Sub-D (DB9) Female connector RS422 Signal name

Pin nr.

RS422TXP 1

RS422TXN 2

RS422RXP 3

RS422RXN 4

COMMS GND 5

Not connected 6 Not connected 7 Not connected 8 Not connected 9

4.3.5 Connector SVP 71

SVP71 Connections

Signal name Pin nr.

COMMS GND 1

RS232 TX 2

RS232 Rx 3

Power (9-55VDC) 4 Not connected 5

Ground 6

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4.3.6 Test cable for SVP 71

Connections on test cable SVP71 only Signal name

Pin nr.

Recommended connec-tion to DB9 Female for PC connection

COMMS

GND

Black 1 pin 5

RS232 TX Green 2 Pin 2 RS232 Rx Brown 3 Pin 3 Power (9-

55VDC)

Blue 4 To battery

Not con-nected

Yellow 5

Ground Blue/Brown 6 To battery These colors are only valid for the cable supplied by Reson.

The test cable for SVP 71 has flying leads when supplied.

To connect the SVP to a PC, we recommend using the connections listed in the table.

The connector is manufactured by Birns (www.birns.com / www.aquamate.biz ).

Use mating connector: Birns-MC-IL06F.

The mating connector is available as a pigtail from RESON and from Birns with various cable length options.

The connector can be submerged in (clean) sea water without being mated, and it is designed to allow mating under water.

SVP-7x Operators Manual rev.1.02/2006 53 Page

Protective caps must be used if the probe is submerged for extended periods without a cable attached.

If ordering the connector directly from Birns, we recom-mend that the cable colors are connected to pins as in our test cable.

4.3.7 Recommended High grade RS422 cable

Use this cable for applications requiring one or more of the following characteristics:

• High baud-rate

• Long cabling

• High noise immunity

Standard Ethernet cable CAT-5 is electrically well suited for RS422 applications. Use the same wiring as for the standard test cable.

4.3.8 Recommended RS232 cable

This cable may be used for baud rates up to 9600 baud and cable length up to 30m in reasonably shielded condi-tions.

The cable may use straight wires, preferably but not nec-essarily shielded.

Cable manufactured by Belden type 8418 is ideally suited for submerged applications using RS232.

Diameter approx 0.381”.

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Jacket: EPDM - Ethylene Propylene Diene Monomer Rubber

Please obtain datasheet directly from Belden.

SVP-7x Operators Manual rev.1.02/2006 55 Page

APPENDIX A CONTACT INFORMATION

RESON A/S

Denmark Tel: +45 47 38 00 22 Fax: +45 47 38 00 66 E-mail: reson@reson.dk

RESON GmbH Germany Tel: +49 431 720 7180 Fax: +49 431 720 7181 E-mail: reson@reson-gmbh.de

RESON Inc.

USA

Tel: +1 805 964-6260 Fax: +1 805 964-7537 E-mail: sales@reson.com RESON (PTY) LTD.

South Africa Tel: +27217011720 Fax: +27217015720 E-mail: sales@reson.co.za

RESON-Telenav Singapore Tel: +65-6-872-0863 Fax: +65-6-872-1334 E-mail: sales@reson-sea.com.sg

RESON OFFSHORE Ltd.

United Kingdom Tel: +44 1224 709 900 Fax: +44 1224 709 910 E-mail: sales@reson.co.uk

RESON B.V.

Netherlands Tel: +31(0)102451500 Fax: +31(0)102451555 E-mail: info@reson.nl

RESON Mediterranean SRL Italy Tel: +39 051 572 643 Fax: +39 051 574 281 E-mail: info@reson.it

SVP-7x Operators Manual rev.1.02/2006 56 Page

APPENDIX B TECHNICAL SPEC.

SVP 70 SVP 71

Sound velocity Range

1350-1800m/s

Resolution 0.01m/s Accuracy (0-50m) ±0.05m/s Accuracy ±0.25m/s (0-6000m) ±0.25m/s (0-2000m) Sampling rate 20Hz and lower, programmable Sampling mode On request, continuous Connector Birns MCBH9M Birns MCBH6-M Output true RS-232 and RS-true RS-232

Baud rate 2400-115200 Galvanic isolation Yes Output options Direct, filtered, validity Output formats Programmable ASCII Supply 9-55V DC Power 2W Dimensions ex connector

44x 165 x70 mm

Weight 1Kg 650 g Depth 6000m (640 Bar) 2000m (210 Bar) Temperature -20 to +55deg Celsius powered on Temperature for specified accu-racy

-3C to 40 Celsius

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APPENDIX C DATA FORMATS

The formats below are all supported by the SVP-70.

They are only a few examples out of a multitude of possi-bilities. See section 2 for details

In the examples the sound velocity is 1478.32 m/s.

Time since probe start is 12039 ms.

SVP70 User Mode Default output

1478.32<CR><LF>

(NOTE: Compatible with SeaBat Sonar Systems)

SVP-70 User Mode configurable output format

$PSOS<TAB>12039<TAB>1478.32<TAB><CR><LF>

SVP-70 NMEA like output formats

$PRSOS,1478.320*78<CR><LF>

Previous RESON SVP’s

14783<CR><LF>

AML output

1478.32<CR><LF>

Valeport output

1478320<CR><LF>

NMEA output

$PRSOS,1350.000*78<CR><LF>

SVP-7x Operators Manual rev.1.02/2006 58 Page

APPENDIX D INSTALLATION

The SVP 7x should be mounted using the two brackets /metal bands supplied with the unit.

To reduce flow noise impacting other sensors it may be retracted / buried into a sea chest.

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APPENDIX E DRILL FOR BRACKET

ATTENTION

The SVP71 MUST be electrically insulated from other metal parts. Use plate of a plastic material as isolation. A plate is provided in the standard delivery of the SVP 71.

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APPENDIX F SVP 70 TEST CABLE SVP70

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APPENDIX G SVP 71 TEST CABLE

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APPENDIX H SVP 70 DIMENSIONS

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APPENDIX I SVP 71 DIMENSIONS

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APPENDIX J TYPICAL ERRORS

Problem Cause

SVP and receiver not set for same baud rate

Bad characters received from SVP

Comms ground connection not established between SVP pin 1 and receiver Bad connection to receiver

Nothing received from SVP SVP not set (RS232/RS422) according to wiring

Reading 1350.00 m/s

Probe not properly sub-merged, air trapped on transducer surfaces or sig-nificant amount of bubbles in sound path.

Fluctuating readings

Air bobbles trapped on the active surface or the reflec-tor plate. If bubbles exist in the sound path at best the SVP will return the average sound speed but not sound speed of the (air free) me-dium.

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APPENDIX K ACCESSORIES

SVP 70 SVP71

Mounting brackets (pair of 2) Bolts with retention O-rings Test Cable with D-sub connectors ✘

Neoprene installation cable 3m optional Neoprene installation cable 5m optional optional

Neoprene installation cable 10m optional optional

Neoprene installation cable 25m optional Neoprene installation cable 60m optional optional Dummy connector optional optional

Anode ✘

Replacement Anode ✘ optional

Isolation plate (for installations) ✘

Cable locking sleeves