Sercel SN388 Installation Manual

SN388

INSTALLATION

Manual

Documentation No. 0311267

Issue : June 1999

Software version 8.4

In no event shall SERCEL be liable for incidental or consequential
damages or related expenses resulting from the use of this product, or
arising out of or related to this manual or the information contained in it,
even if SERCEL has been advised, or knew or should have known of the
possibility of such damages.

The information in this manual is believed to be accurate and reliable.
However, SERCEL reserves the right to make changes to its products or
specifications at any time, without notice, in order to improve design or
performance and to supply the best possible product.

TABLE OF CONTENTS

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i

9. TABLE OF CONTENTS

9.1

TABLE OF CONTENTS

1. INTRODUCTION ........................................................................................................... 1-1

1.1 OVERVIEW....................................................................................................................1-1

1.2 GENERAL DESCRIPTION .................................................................................................1-1

1.3 CENTRAL CONTROL UNIT (CCU) ............................................................................. 1-2

1.4 FIELD ELECTRONICS................................................................................................ 1-9

2. HARDWARE INSTALLATION ....................................................................................... 2-1

2.1 POWER REQUIREMENTS.........................................................................................2-1

2.2 MOUNTING DIMENSIONS (CAB-MOUNT) ................................................................. 2-1

2.3 CONNECTIONS........................................................................................................2-13

2.4 POWER-UP...............................................................................................................2-26

3. SOFTWARE INSTALLATION OR RE-INSTALLATION ................................................. 3-1

3.1 SOLARIS INSTALLATION OR RE-INSTALLATION....................................................3-1

3.2 YEAR 2000 PATCH................................................................................................... 3-11

3.3 SERCEL SOFTWARE CDROM INSTALLATION (SN388, HCI, PS) ......................... 3-12

3.4 PROCESSING SUPPORT (PS) SOFTWARE PACKAGE INSTALLATION............... 3-13

3.5 VQC SOFTWARE PACKAGE INSTALLATION.........................................................3-14

3.6 GETTING STARTED................................................................................................. 3-15

3.7 STARTUP CONFIGURATION...................................................................................3-16

3.8 POWER-OFF ............................................................................................................ 3-17

3.9 IF YOU ARE NEW TO WINDOWING SYSTEMS......................................................3-18

3.10 IF SN 388 SOFTWARE IS SUPPLIED TO YOU ON CARTRIDGES....................... 3-19

4. FIELD EQUIPMENT LAYOUT ....................................................................................... 4-1

4.1 TYPICAL DEPLOYMENT EXAMPLES........................................................................ 4-1

4.2 MAXIMUM CABLE LENGTH ..................................................................................... 4-15

4.3 PSU MANAGEMENT................................................................................................. 4-16

4.4 DETOURS.................................................................................................................4-18

4.5 SPECIFIC FEATURES OF B-TYPE AND UL-TYPE FIELD UNITS ...........................4-20

TABLE OF CONTENTS

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ii

5. MAINTENANCE ............................................................................................................. 5-1

5.1 CHANGING THE HARDWARE CONFIGURATION ..................................................... 5-1

5.2 ADJUSTING THE TCXO OSCILLATOR ON THE AXI BOARD...................................5-1

5.3 SN 388 DAILY AND MONTHLY FIELD TESTS........................................................... 5-2

5.4 RECONFIGURING THE HCI WITH A NEW TYPE OF PRINTER................................ 5-3

5.5 CHANGING CD488-B SCSI ADDRESS......................................................................5-5

5.6 ACCESSING THE AIR FILTER INSIDE THE CD488-B...............................................5-6

5.7 VERITAS V12 PLOTTER SETTINGS.......................................................................... 5-7

5.8 CD488-B POWER-ON TESTS.................................................................................... 5-8

5.9 CHANGING CD490-E SCSI ADDRESS ...................................................................... 5-8

5.10 DISPLAYING SCSI ADDRESS ON CD490-E OPERATOR PANEL..........................5-9

5.11 GS612 PLOTTER CONFIGURATION.....................................................................5-10

5.12 CD490-E EQUIPPED WITH M2488E DRIVE..........................................................5-11

6. HOW TO ENTER ASCII DATA INTO THE SN388 ......................................................... 6-1

6.1 OVERVIEW.................................................................................................................6-1

6.2 INTERFACING ............................................................................................................ 6-1

6.3 RS232 COMMUNICATIONS BETWEEN A TERMINAL AND AN SN388 .................... 6-2

6.4 XDEV ADAPTOR ........................................................................................................ 6-3

7. MULTI-SCREEN & X-TERMINAL INSTALLATION ....................................................... 7-1

7.1 MULTI-SCREEN INSTALLATION................................................................................ 7-1

7.2 X-TERMINAL INSTALLATION ..................................................................................... 7-4

8. MULTI-MODULE INSTALLATION ................................................................................. 8-1

8.1 OVERVIEW.................................................................................................................8-1

8.2 HARDWARE REQUIREMENTS OR CHANGES FOR MULTI-MODULE OPERATIONS8-3

8.3 SN388 MULTI-MODULE CONFIGURATIONS............................................................. 8-5

8.4 TCXO ADJUSTMENT.................................................................................................. 8-9

8.5 DETAILED CONNECTION DIAGRAMS ......................................................................8-9

APPENDIX 1 APM & PAM PLUG PINOUT
APPENDIX 2 FIELD CABLES
APPENDIX 3 APM & PAM POWER-ON READOUT CODES
APPENDIX 4 SU POLARITY

0311390

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0311390

III. WARRANTY

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INTRODUCTION

Overview

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1-1

1. INTRODUCTION

1.1 Overview

This manual contains installation information, a few instructions for the operator to
get started, and reference information that will help you select an SN 388
configuration tailored to your needs. General reference information (SEGD format,
specifications, etc.) is contained in the REFERENCE Manual.

Operating instructions are not provided in the form of a traditional manual, as any
help information needed appears direct on-screen and is just one click away at all
times once the system is started.

For detailed information on peripherals (printer, camera, etc.) see the respective
manufacturers' documentation.

1.2 General description

The SN 388 is a large capacity, high resolution system designed for land seismic
data acquisition. It derives its high reliability and versatility from SERCEL's
unequalled experience in cable telemetry systems and from the use of the most
advanced electronics and workstation technology.

The SN 388 is composed of a Central Control Unit (CCU) and electronic field
equipment (SU, CSU, PSU) interconnected by electric cables. The CCU consists of
a Human Computer Interface (HCI workstation) and one or more 1200-channel
acquisition modules :

- PAM : Portable Acquisition Module

- APM : Acquisition and Processing Module

SUs, performing data acquisition, are remotely powered through the
interconnecting cable, from standard 12 VDC batteries, evenly distributed along the
spread, via PSUs.

INTRODUCTION

CENTRAL CONTROL UNIT (CCU)

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1-2

2400 CH

MODULE

PRINTER

X

TERMINAL

WORK

STATION

PLOTTER

TAPE OR

CARTRIDGE

DRIVE

HCI

CENTRAL CONTROL UNIT BLOCK DIAGRAM

2400 CH

MODULE

1 to 16

2400 CH

MODULE

1.3 CENTRAL CONTROL UNIT (CCU)

The SN 388 Central Control Unit hardware, relying on the UNIX



operating system

and computing network architecture offers maximum expandability and flexibility.

• The HUMAN COMPUTER INTERFACE (HCI) is dedicated to system
interaction with the operator, through a fast and comprehensive software
package specially designed to ease geophysical operations in the field.

• Data acquisition and optional correlation and stack processing are carried
out by one or more 1200 CH MODULES (up to 16) to reach the maximum
capacity of 19200 channels at 2-ms sample rate or equivalent data rate
capacity.



UNIX, ETHERNET are registered trademarks of UNIX Systems Laboratories Inc, Xerox

Corporation.

INTRODUCTION

CENTRAL CONTROL UNIT (CCU)

0311267 Issue : April 1998

1-3

Expandable and powerful Ethernet data network is used to connect the
HCI to the various modules.

The raw or processed data are recorded on magnetic media, either a reel
or a cartridge drive.

Digital filtering may be performed on the recorded or playback data, to
display notch- or bandpass-filtered seismic traces on a digital camera.

• Peripheral equipment such as a printer or digital camera can be connected
to the CCU to provide data, operation log and parameter hard copy. The
system has the capability to display a noise monitor of the complete
spread in real time, without any delay or missing data due to segmented
processing.

1.3.1 HUMAN COMPUTER INTERFACE (HCI)

The operator controls the complete system through a HUMAN COMPUTER
INTERFACE (HCI) based on a workstation with a high resolution colour monitor, a
keyboard and a mouse. A multi-windowing system allowing flexible and versatile
screen extensions gives immediate access to all parameter settings.

The major functions of HCI software include :

- Normal operation control (user-friendly parameter setup, update, and
display for the entire system, including all VE416/VE432 Vibrator
electronics parameters).

- Permanent high-resolution graphic display of the complete field electronics
connected to the CCU, including ancillary units and the shot point. The
graphic display allows interactive graphic selection of the spread, and
energy monitoring prior to and during the shot.

- Easy to set up and update shotpoint planning.

- Preplanning In/Out capability : SN 388 parameter script files can be saved
to and/or loaded from an auxiliary computer. Compatibility with a
standalone processing support converter is provided.

- Neat display of system activity.

- Display, analysis and storage of spread test results.

- Automatic log of observer report data.

- Graphic display of planned source and receiver positions, possibly
superimposed on a digitized map and/or a graticule. Real-time tracking of
actual vibrator positions and centre of gravity of actual source position
(with VE416/VE432 and GPS).

- Source and Receiver attributes (e.g. vibrator peak force, geophone
impedance etc.) can be colour-coded and displayed geographically.



UNIX, ETHERNET are registered trademarks of UNIX Systems Laboratories Inc, Xerox Corporation

INTRODUCTION

CENTRAL CONTROL UNIT (CCU)

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1-4

- Service Vehicle Tracking function. If equipped with MRU units, service
vehicles appear on the survey map. They can send an alarm code to the
base station and receive messages (e.g. a waypoint) from it. The trackline
and identification of each tracked vehicle can be plotted on the survey
map.

- ON-LINE real-time VQC processing. Traces can be input to the VQC
application as soon as they are acquired and processed, so you can
monitor the phase or distortion or force of the vibrator source signal (on
auxiliary traces) in real time.

- Printout of all parameters, and hard copy of daily production report (easy
to customize), using a standard line printer attached to the HCI.

- Automatic CCU acceptance tests.

- Graphical VE416/VE432 QC interface.

- Online help information.

In portable operations, where weight and volume are critical, the HCI is configured
as a fully portable laptop workstation with a single monitor.

For truckmounted operations, with the X-window system , additional X-terminals
may be connected to the desktop configuration to offer comfortable and permanent
display of multiple windows for system parameter viewing or entry.

For vibroseis operations, the standard HCI software has the capability to perform
complete remote control of the VE416/VE432 vibrator electronics parameters.
Parameter entry is done on the HCI, which emulates the complete initialization
software of the VE416/VE432 Digital Pilot Generator. During operations, the
VE416/VE432 vibrator status information is received by the HCI for storage and
analysis. For other types of vibrator control systems, remote control is performed
through the necessary handshake signals.

1.3.2 ACQUISITION AND PROCESSING MODULES
(APM/PAM)

The parameters entered through the HCI are downloaded into the Acquisition and
Processing Module (APM) or Portable Acquisition Module (PAM).

The major functions performed by both the APM and PAM include :

- interfacing with the field electronics,

- generating the Firing Order and sensing the Time Break,

- seismic line management and control,

- auxiliary line control,

- collecting the data from the field electronics,

- formatting the data to and from the tape transport and to the digital
camera,

- collecting system status data to be returned to the HCI.



TM :Xwindow is a trademark of Massachusetts Institute of Technology.

INTRODUCTION

CENTRAL CONTROL UNIT (CCU)

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1-5

APM functions also include :

- noise editing (Zeroing/Clipping/Diversity Stack)

- correlation and stacking.

The following boards are used in both the APM and PAM :

LIO : Line Input/Output interface

LCP : Line Controller Processor

MPM : Main Process Memory

AXC : Auxiliary Line Controller

TTC : Tape Transport Controller

TTS : SCSI Tape Transport controller

Two more boards are used in the APM :

NEP : Noise Elimination Processor

FTP : Fourier Transform Processor

Configuration Boards

AXC LIO LCP MPM NEP FTP TTC or TTS

1200 ch PAM 1 1 1 1

(MM16-1)

- - 1

480/30 ch APM 1 1 1 3

(MM16-1)

1 1 1

600 ch APM 1 1 1 3

(MM16)

1 1 1

1200 ch APM 1 1 1 3

(MM16)

2 2 1

Table 1-1 SN 388 PAM/APM board configurations

Every effort has been made in designing the hardware of the PAM and APM to
enhance performance while reducing size :

• Zero dead time operation (unless limited by tape drive performance). The
1200-channel PAM and APM modules, organized around a pipe-line
architecture, achieve such a speed that vibrator drivers and dynamite
shooters will not need to wait for the acquisition system to be ready.

INTRODUCTION

CENTRAL CONTROL UNIT (CCU)

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INTRODUCTION

CENTRAL CONTROL UNIT (CCU)

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1-7

INTRODUCTION

CENTRAL CONTROL UNIT (CCU)

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1-8

• Minimum weight and volume.
For portable dynamite operations, the PAM houses all necessary

electronics to acquire 1200 Channels at 2-ms sample rate, within a 22-kg
unit (0.088 m3).

The APM which, in addition to acquisition itself, performs correlation and
stack operations, is packaged within a single 37-kg unit (0.111 m3), for

configurations up to 1200 Channels at 2-ms sample rate.
To facilitate configuration changes and equipment maintenance, the five

boards dedicated to acquisition and recording are identical and fully
interchangeable between the PAM and APM modules.

1.3.3 MULTI-MODULE INTERFACE

To extend the capacity of the system, an MMI-4 unit is used, allowing up to four
APM or PAM acquisition modules to be connected together (increasing the
capacity up to 4800 channels).

An MMC-4 unit is also available, to attach a camera to up to four acquisition
modules.

1.3.4 PERIPHERAL EQUIPMENT

• • Tape drives

Reel or cartridge tapes can be used as magnetic media on SN 388 systems, for
recording in demultiplexed format :

- the MS8TT or SS8TT tape drive provides recording on a widely used 6250
b.p.i. 1/2 inch tape reel, housed in two waterproof and portable units,
specially designed for harsh and portable seismic environments.

- the CD 480 or 488 CARTRIDGE drive makes it possible to record a 3480
IBM compatible cartridge tape, directly in the field. For dual drive
recording, the standard software provides alternate or simultaneous
recording without any additional devices.

For very large configurations, parallel multiple drive recording makes it
possible to override the delay which may be induced by the speed
limitation of a single drive.

• • Digital camera

An external digital camera is used to generate a paper record of the acquired
seismic data, either in read-after-write∗ or in play-back mode.

∗

with MS8TT tape drive.

INTRODUCTION

FIELD ELECTRONICS

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1-9

1.4 FIELD ELECTRONICS

The SN 388 field electronic equipment consists of units which are interconnected
by electric cables. All field units are packaged into a totally waterproof aluminium
casting. They have been designed to fully operate in the temperature range of -40
to + 70° C.

The SN 388 SU's are manufactured with custom-designed integrated circuits. This
offers the user field upgradable packaging which contributes to the maximum
flexibility at the lowest cost, and enhances the performance of the system :

-1 channel per SU for high-resolution surveys,

-3 channels per SU for 3-component high-resolution surveys,

-6 channels per SU for large 3-D surveys.

SU-1

SU-1

SU-1

SU-3

SU-3

SU-3

SU-6 SU-6

INTRODUCTION

FIELD ELECTRONICS

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1-10

1.4.1 24-BIT STATION UNIT (SU)

SN 388 advanced technology reduces the complete seismic channel with its 24-bit
stream A/D converter to a plug-in module the size of a matchbox.

The technology allowed the design of an ultra-compact SU which is field
upgradable by plugging in (or out) modules. This versatile SU covers all the various
kinds of seismic acquisitions, at the optimum cost. Within the same casting, by
installing the proper number of seismic channel modules, the user can select the
desirable configuration :

-1-channel SU

-3-channel SU

-6-channel SU

To prevent any incorrect geophone string connection, the spread in operation must
be composed of homogeneous-type SUs.

However, to add flexibility for P-wave acquisition, the three-channel SU can be
used as a one-channel SU.

• • No battery pack

The SN 388 does not require any battery pack to be associated with each SU. With
the SN 388's extremely low power consumption (240 mW per channel) the number
of batteries required along a line is minimum.

For portable or heliportable operations the SN 388 station unit comes with an
unprecedented ratio of 650 g per channel.

• • Analog-filter-free and ideal seismic response

Taking advantage of the large dynamic range and the very low distortion of the SN
388's 24-bit-stream A/D converter, the seismic channels are free from any analog
filters. With this design, undesirable phase shifts and temperature drifts due to
analog components are suppressed to obtain the ideal seismic response with
either minimum or linear phase shift. As a result, filter settings at the field level are
no longer required, which precludes any unrecoverable error arising from incorrect
settings. (Sophisticated filtering is preferable where it is non-destructive, that is at
the playback or processing stage).

• • 24-bit built-in test generator

A 24-bit ultra-low distortion built-in test generator is integrated into every SU, in
order to perform a remote check of the complete acquisition performance, at full
specification, from the CCU without any external oscillator.

INTRODUCTION

FIELD ELECTRONICS

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1-11

1.4.2 CROSSING STATION UNIT

A Crossing Station Unit (CSU) is required to connect each line to the previous line
or to the CCU module. A low-attenuation cable is used for this transverse
connection, providing a digital link over a maximum distance of 600 m without a
repeater.

A 12 V standard battery is connected to each CSU to power its internal circuits as
well as the near SU's in the relevant spread line (see also PSU).

BATT

SU SU

SU

PSUCSU

BATT

BATT

SU SU SU PSU

CSU

BATT

CCU

1.4.3 POWER STATION UNIT

A Power Station Unit (PSU) is required to regenerate the DC voltage distributed
over the line cables to provide power to the SU's. A 12 V standard battery is
connected to each PSU.

The number of PSUs in operation depends on the SU configuration ; one PSU is
required :

- every 40 channels with the 1-channel SU,

- every 90 channels with the 3-channel SU,

- every 48 channels with the 6-channel SU.

The CSU acts as a PSU for the line in which it is inserted.

INTRODUCTION

FIELD ELECTRONICS

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1-12

1.4.4 BU-6 (Bay-Cable unit)

To extend the versatility of the SN 388 telemetry system, a BAY-CABLE
ACQUISITION UNIT (BU-6) is available for transition zones and shallow water
operations. The BU-6 package which houses 6 seismic channels including the
SN 388 proprietary 24-bit A/D converter, is directly mounted on a multi-conductor
cable incorporating a strength member, particularly designed for shallow or tidal
areas, for which multiple windings and unwindings on a small diameter winch are
required. The BU-6 is fully controlled by the SN 388 CENTRAL CONTROL UNIT.
For safety operations, within marine environment, the BU-6 is operating under a
± 24 V DC voltage which is supplied by the central unit through the interconnecting
bay cables. No immersed power supplies are required.

For mixed-operation land and transition zones, the BU-6 is fully compatible and can
be mixed with the SN 388 standard 6 channel Station Unit (SU-6). In that type of
operations, the land section is powered by the 12 VDC batteries associated with
the SN 388 PSUs.

1.4.5 MICRO WAVE LINK

The SN388 Micro-Wave Link (MWL) is used to replace an SN388 extension cable
in areas where cable laying is made difficult by field obstacles such as rivers, cliffs,
canyons, etc.

It provides a bi-directional radio link relaying the telemetry data, the field unit power
control and the telephone.

A ± 24 VDC power supply is also included to power up the SUs connected at either
end of the link.

1.4.6 CABLES

• • Line cables

- for the single- or 3-channel SU, the line cable provides digital transmission
and remote power. The receiver group is directly connected to the SU
socket, to achieve the highest-resolution performance,

- for the 6-channel SU, the functions of the line cable include digital
transmission, remote power, and acquisition of 6 receiver groups. The
receiver groups are connected to the cable take-outs.

• • Transverse

To connect the lines to the CCU, transverse cables are used (see CSU), between
any two successive CSUs and between the nearest CSU and the 1200-CH
MODULE.

• • Detour

When a detour is needed along a seismic line, an extension cable is laid down and
a PSU is required at each end of the extension cable.

INTRODUCTION

FIELD ELECTRONICS

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1-13

1.4.7 LINE TESTER

For large 3-D operations, in order to check the lines deployed ahead of the spread,
a LINE TESTER (LT 388) makes is possible to perform transmission and receiver
tests on a complete connected line, without CCU being needed.

SU

LT 388

SU

1.4.8 QUICK TESTER

When plugged into the LINE connector of any field unit, the SN 388 Quick Tester
allows quick checking of the line voltage (VLL) and of the performance of a remote
control signal (PWCT)

NOTE : The VLL voltage on the AUXILIARY line (24 V instead of 48 V) cannot be

tested with the Quick Tester.

Quick tester

INTRODUCTION

FIELD ELECTRONICS

0311267 Issue : April 1998

1-14

1.4.9 TEST AND MAINTENANCE SYSTEM

The TEST AND MAINTENANCE SYSTEM (TMS 388) is designed for testing or
troubleshooting all types of SN 388 field units.

The TMS 388 is composed of a PC micro computer, a test unit (TMU), a cable unit
(TCU) used to simulate line cables, and a test signal generator (TGU).

TGU

Unit under test

PC

TCU

TMU TMS 388

J1

J2

J3

J4

6 1

LINE 1 LINE 2

INPUT/
BATT

XDEV