SBG Systems EKINOX 2 Subsea Series User manual

EKINOX 2 Subsea series
Inertial Navigation Systems
Hardware Manual
intro
Document EKINOX2SU SEAHM.1.2
Revision 1.2 - May 29, 2018
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EKINOX 2 Subsea – Hardware Manual EKINOX2SU SEAHM.1.2
Revision history
Rev. Date Author Information
1.2 May 29, 2018 Raphaël Siryani [EKI2SU HM-5] Removed not applicable advises regarding magnetometers
1.1 Apr 10, 2018 Raphaël Siryani [EKI2SU HM-3] Fixed main connector pin out, pin 18 and 22 were reversed
[EKI2SU HM-2] Added Qinertia Port Processing Software section
[EKI2SU HM-1] Updated company address
1 Jul 12, 2017 Alexis Guinamard First version of this document
© 2007 – 2018, S G Systems SAS. All rights reserved. Information in this document is subject to change
without notice. Copy or redistribution of this document is forbidden without express authorization of
S G Systems.
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EKINOX 2 Subsea – Hardware Manual EKINOX2SU SEAHM.1.2
Index
Terminology............................................................................................................................................................ 5
1. Introduction....................................................................................................................................................... 6
1.1. Ekinox 2 INS Overview................................................................................................................................ 6
2. Performance specification................................................................................................................................. 7
2.1. Inertial measurement unit......................................................................................................................... 7
2.1.1. Accelerometers......................................................................................................................................................................... 7
2.1.2. Gyroscopes............................................................................................................................................................................... 7
2.2. External Aiding sensors............................................................................................................................ 7
2.3. Orientation and Navigation Performance................................................................................................ 8
2.3.1. Common specifications........................................................................................................................................................... 8
2.3.2. Orientation and navigation.................................................................................................................................................... 8
2.3.3. Heave performance................................................................................................................................................................. 9
2.3.4. Real time Performance monitoring....................................................................................................................................... 9
3. Mechanical specifications................................................................................................................................ 10
3.1. Overview................................................................................................................................................... 10
3.1.1. Main Specifications................................................................................................................................................................. 10
3.1.2. Device mechanical alignment................................................................................................................................................ 10
3.1.3. Origin of measurements......................................................................................................................................................... 11
3.1.4. Device label.............................................................................................................................................................................. 11
3.2. EKINOX 2 Subsea EL mechanical outline (200 m).................................................................................. 12
3.2.1. Front view............................................................................................................................................................................... 12
3.2.2. Top view................................................................................................................................................................................. 13
3.2.3. ottom view.......................................................................................................................................................................... 13
3.3. EKINOX2 Subsea ED mechanical outline (6 000 m)............................................................................... 14
3.3.1. Front view............................................................................................................................................................................... 14
3.3.2. Top view................................................................................................................................................................................. 15
3.3.3. ottom view.......................................................................................................................................................................... 15
4. Electrical specifications................................................................................................................................... 16
4.1. Main connector......................................................................................................................................... 16
4.1.1. Main connector pin out........................................................................................................................................................... 16
4.2. Electrical specifications........................................................................................................................... 18
4.3. Typical wiring........................................................................................................................................... 19
4.3.1. RS-232 basic communications.............................................................................................................................................. 19
4.3.2. RS-422 basic communication............................................................................................................................................... 19
4.3.3. GNSS connection in RS-232 mode....................................................................................................................................... 20
4.3.4. Triggering external devices with the sync Out.................................................................................................................... 20
4.4. Typical connection topologies................................................................................................................. 21
4.4.1. Ekinox2-U in marine application............................................................................................................................................ 21
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EKINOX 2 Subsea – Hardware Manual EKINOX2SU SEAHM.1.2
5. Interfaces specifications................................................................................................................................. 22
5.1. Interfaces Overview................................................................................................................................. 22
5.2. Ethernet specifications........................................................................................................................... 22
5.2.1. Accessing the Ekinox web page............................................................................................................................................ 22
5.3. Serial interfaces...................................................................................................................................... 23
5.4. Supported protocols................................................................................................................................ 23
5.5. Synchronization Inputs and outputs...................................................................................................... 23
5.5.1. SYNC In A, , C, D and E........................................................................................................................................................ 23
5.5.2. SYNC OUT A, ...................................................................................................................................................................... 24
5.6. Connections Mapping............................................................................................................................. 24
5.6.1. Ekinox2-M version................................................................................................................................................................. 24
5.6.2. Ekinox2-U version................................................................................................................................................................. 24
5.7. Internal Datalogger.................................................................................................................................. 24
6. Important notices........................................................................................................................................... 25
6.1. Maintenance............................................................................................................................................ 25
6.1.1. Cleaning.................................................................................................................................................................................. 25
6.2. Absolute maximum ratings.................................................................................................................... 25
6.3. Support................................................................................................................................................... 26
6.4. Warranty, liability and return procedure................................................................................................ 26
7. Appendix A: Ordering codes and Accessories.................................................................................................. 27
7.1. Ekinox 2 Subsea ordering codes............................................................................................................... 27
7.2. Transport Cases........................................................................................................................................ 27
7.2.1. CASE-EKI-03........................................................................................................................................................................... 27
7.3. Split ox for easy connection................................................................................................................... 28
7.3.1. SPLIT OX-SU ....................................................................................................................................................................... 28
7.3.2. SPLIT OX-SU -S................................................................................................................................................................... 28
7.3.3. SPLIT OX-SU -T................................................................................................................................................................... 28
7.4. Associated Software............................................................................................................................... 29
7.4.1. SW-AEK-SDK (Software Development Kit)........................................................................................................................... 29
7.4.2. SW-QINERTIA-PRO (GNSS/INS Post Processing Software)................................................................................................ 29
7.5. Cables....................................................................................................................................................... 30
7.5.1. CA-AEK-SU -DPT500-10M.................................................................................................................................................... 30
7.5.1.1. Cable Construction......................................................................................................................................................... 30
7.5.1.2. Electrical characteristics............................................................................................................................................... 30
7.5.1.3. Mechanical characteristics............................................................................................................................................ 31
7.5.1.4. Cable wiring.................................................................................................................................................................... 31
7.5.2. CA-AEK-SU -DPT500-20M................................................................................................................................................... 32
7.5.3. CA-AEK-SU -DPT6000-5M................................................................................................................................................... 32
7.5.3.1. Cable Construction........................................................................................................................................................ 32
7.5.3.2. Electrical characteristics.............................................................................................................................................. 33
7.5.3.3. Mechanical characteristics........................................................................................................................................... 33
7.5.3.4. Cable wiring.................................................................................................................................................................. 34
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EKINOX 2 Subsea – Hardware Manual EKINOX2SU SEAHM.1.2
Terminology
ADC: Analog to Digital Converter
AHRS: Attitude and Heading Reference System
DHCP: Dynamic Host Configuration Protocol
DVL: Doppler Velocity Log
EKF: Extended Kalman Filter
EEPROM: Electrically-Erasable Programmable Read-Only Memory
FIR: Finite Impulse Response (filter)
FTP: File Transfer Protocol
FS: Full Scale
FOG: Fiber Optic Gyroscope
GNSS: Global Navigation Satellite System
GPS: Global Positioning System
IIR: Infinite Impulse Response (filter)
IMU: Inertial Measurement Unit
INS: Inertial Navigation System
IP: Internet Protocol
L L: Long aseline
MAC (address): Media Access Control
MEMS: Micro Electro-Mechanical Systems
NED: North East Down (coordinate frame)
NA: Not applicable
NMEA (NMEA 0183): National Marine Electronics Association (standardized communication protocol)
PPS: Pulse Per Second (signal)
RAM: Random Access Memory
RMA: Return Merchandize Authorization
RMS: Root Mean Square
RTCM: Radio Technical Commission for Maritime Services (Protocol)
RTK: Real Time Kinematics
SI: International System of Units
T D: To e Defined
TCP: Transmission Control Protocol
UDP: User Datagram Protocol
UTC: Coordinated Universal Time
US L: Ultra Short ase Line
VRE: Vibration Rectification Error
WGS84: World Geodetic System 1984
WMM: World Magnetic Model
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EKINOX 2 Subsea – Hardware Manual EKINOX2SU SEAHM.1.2
1. Introduction
Ekinox 2 Subsea series are state of the art, MEMS based Motion
Reference Unit (Ekinox2-M) and Inertial Navigation System
(Ekinox2-U) which achieve exceptional orientation & navigation
performance in a compact subsea enclosure.
Ekinox 2 Subsea series include a cutting edge Inertial Measurement
Unit (IMU) and run an on-board enhanced Extended Kalman Filter
(EKF). In addition to vessel orientation, the Ekinox 2 subsea will
provide accurate ship motion data (heave, surge and sway) at high
rate. Created to achieve the best accuracy for every application,
Ekinox 2 Subsea also integrates data from various aiding
equipment such as GNSS, DVL, etc.
To achieve the best performance in every project, specific error
models have been implemented to meet applications requirements. An embedded web interface enables
easy configuration and a wide connectivity as well as standard protocols output provide direct integration
into existing applications.
This second generation of Ekinox Subsea remains fully compatible with previous Ekinox Subsea series.
1.1. Ekinox 2 INS Overview
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Figure 1.1: The Ekinox 2 Subsea
Figure 1.2: Ekinox Subsea simplified block diagram
IMU DATA FUSION
Coning & Sculling
integrals @ 1 kHz
3 Axis
Gyroscopes
3 Axis
Accelerometers
EKF and output
@ 200 Hz
POWER
ETHERNET
FTP
CAN
SERIAL
Data loggerGNSS
A C D
Aiding Equipments
» Navigation: 2x RTK GPS/GNSS
» Heading: Dual Antenna GPS/GNSS
» Velocity: Odometer, DVL

EKINOX 2 Subsea – Hardware Manual EKINOX2SU SEAHM.1.2
2. Performance specification
2.1. Inertial measurement unit
The IMU is the core component of an inertial navigation system. Leveraging on MEMS technology and an
innovative proprietary integration, the EKINOX 2 IMU delivers an exceptional performance while
maintaining a reasonable cost.
2.1.1. Accelerometers
The EKINOX 2 IMU contains a set of 3 MEMS capacitive accelerometers. Coupled with advanced filtering
techniques and sculling integrals, these accelerometers will provide quartz performance level. Thanks to a
very low VRE, the performance is maintained in highly vibrating environments.
A2 Remarks
Full scale ( g )± 8
Velocity Random Walk (µ g /√hz) 7 Allan variance – @ 25°C
In run bias instability (µ g )2 Allan variance – @ 25°C
Vibration Rectification Error (µ g / g ²) <200 VRE – 20 Hz – 2 kHz
andwidth (Hz) 433 Attenuation of 3 d
Orthogonality (°) < 0.02 Over temperature range
2.1.2. Gyroscopes
The set of 3 high end tactical grade MEMS gyroscopes is sampled at 2.3 kHz. A specific integration design
as well advanced signal processing (FIR filters, coning integrals) ensure best performance in vibrating
environments.
G4 Remarks
Full scale (°/s) ± 300
In run bias instability (°/hr) 0.5 Allan variance – @ 25°C
Angular Random Walk (°/√hr) 0.14 Allan variance – @ 25°C
andwidth (Hz) 60 Attenuation of 3 d
Orthogonality (°) < 0.02 Over temperature range
2.2. External Aiding sensors
The Ekinox2-M accepts a single external GNSS receiver connection to improve orientation performance
The Ekinox2-U accepts up to two external GNSS receivers to provide navigation data and improve
orientation performance In addition, a DVL can be connected on Ekinox2-U as velocity aiding input.
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EKINOX 2 Subsea – Hardware Manual EKINOX2SU SEAHM.1.2
2.3. Orientation and Navigation Performance
All specifications are rated to 1σ, over -40°C to +75°C unless otherwise stated.
These specifications have been obtained by field tests, using typical mission scenarios and comparison to
reference units using post-processing. Outage performance validated by simulation of repeated, pure GNSS
outages, separated by at least 200s of optimal GNSS condition, compared to a reference RTK trajectory.
Performance parameters may be affected in multi-path and poor GNSS reception environments such as
Urban canyons.
For each application, we present the specified accuracy for the following positioning modes:
●SP: Single Point mode and is the default L1 GPS fix quality
●RTK: Real Time Kinematics with a typical 1 cm accuracy position
●PP: Post Processed data using Inertial Explorer with at least Precise Point Positioning data
2.3.1. Common specifications
Performance Remarks
Measurement range 360° in all axes, no mounting limitation Solid state sensors
Orientation noise < 0.02° RMS Static
2.3.2. Orientation and navigation
All specifications are valid with dual antenna aiding for typical marine survey trajectories.
Outage
Duration Positioning Mode Position Accuracy Velocity Accuracy Attitude Accuracy (°)
Horizontal Vertical Horizontal Vertical Roll / Pitch Heading
0 s
SP 1.20 m 2.0m 0.05 m/s 0.05 m/s 0.03° 0.08 (baseline > 2m)
0.05 (baseline > 4m)
RTK 0.01 m 0.02m 0.02 m/s 0.02 m/s 0.02°
PP 0.01 m 0.02 m 0.01 m/s 0.01 m/s 0.015° 0.03°
10 s
SP 2.2 m 2.5m 0.1 m/s 0.05 m/s 0.1° 0.1° (baseline > 2m)
0.08° (baseline > 4m)
RTK 0.3 m 0.1m 0.05m/s 0.03 m/s 0.1°
PP 0.05 m 0.03 m 0.02 m/s 0.01 m/s 0.02° 0.03°
30 s
SP 4.0m 2.5 m 0.3m/s 0.15 m/s 0.15° 0.15° (baseline > 2m)
0.13° (baseline > 4m)
RTK 3.0 m 0.75 m 0.25 m/s 0.1 m/s 0.15°
PP 1.0 m 0.3 m 0.05 m/s 0.03 m/s 0.04° 0.05°
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2.3.3. Heave performance
Real Time Heave ShipMotionHP Remark
Range 50 meters 50 meters Automatic adjustment to every sea conditions
Period 0 to 20 s 0 to 40 s
Accuracy 5 cm or 5% 2.5 cm or 2.5 % Whichever is greater; Velocity aided heave
Mode Real time, auto tuning Fixed 450s delay On board computation
2.3.4. Real time Performance monitoring
The Extended Kalman filter provides feedback about its performance. The following thresholds are defined
for the Ekinox series:
Threshold Comments
Attitude Valid 0.3° / 0.07° AHRS / Normal INS mode
Heading Valid 0.5° / 0.2° AHRS / Normal INS mode
Velocity Valid 0.2m/s Total velocity error (3D)
Position Valid 1m Total position error (3D)
Note: The thresholds are less accurate in AHRS mode, when there is no GNSS aiding available. Full
performance can be reached with GNSS aiding
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EKINOX 2 Subsea – Hardware Manual EKINOX2SU SEAHM.1.2
3. Mechanical specifications
3.1. Overview
The Ekinox Subsea enclosure is composed of titanium parts, one for the cover and one for the base plate.
The device uses high quality alloys and connectors to offer a depth rating of 200 m or 6 000 m, and good
resistance to seawater environment.
3.1.1. Main Specifications
The table below summarizes all mechanical and environmental specifications.
Specifications Titanium 200 (EL) Titanium 6 000 (ED)
Depth Rating 200m 6 000m
Weight in air 1.55 Kg (3.4 lbs) 2.34 Kg (5.2 lbs)
Weight in water 0.86 Kg (1.9 lbs) 1.43 Kg (3.2 lbs)
Diameter 8.7 cm (3.4”) 9.2 cm (3,6”)
Height 13.8 cm (5.4”) 15.5 cm (6.1”)
Shocks 500 g for 0.3 ms
Operating Vibrations 3g RMS – 20Hz to 2 kHz as per MIL-STD-810G
Operating Temperature range -20 to 60°C (-4 to 140°F)
Storage Temperature range -20 to 60°C (-4 to 140°F)
MT F (computed) 50.000 hours
Calibration interval None required, maintenance free
3.1.2. Device mechanical alignment
For best measurement accuracy, a good mechanical alignment is required. During manufacturing, the
Ekinox measurement frame has been carefully aligned to 0.02° with the base plate for roll, pitch and yaw
angles.
To ease the yaw alignment (X axis), the base plate features two alignment holes Ø 4 mm H8 that
guarantees with two taper pins Ø 4 mm h7 a yaw alignment better than ±0.04°.
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EKINOX 2 Subsea – Hardware Manual EKINOX2SU SEAHM.1.2
3.1.3. Origin of measurements
The Ekinox 2 offers the possibility to output data at different measurement points.
The default center of measurement is located on top of Ekinox enclosure. It is represented on the
mechanical outlines by the symbol. This point is defined to simplify installation.
Alternatively, user can select between two other center of measurement points:
●Alignment hole (aligned to the bottom of the base plate)
●are IMU center of measurement, represented by the symbol.
3.1.4. Device label
S G Systems manufacturing process is based on EN-9100 system with individual and full traceability of
every component and operation. Each Ekinox 2 is identified by a unique serial number that can be used to
trace all operations during the product lifetime such as manufacturing, calibration, tests and repairs.
In addition to a unique serial number, a product code is used to define exactly the device type and options.
Finally, the Ekinox 2 features an Ethernet interface and a unique MAC address is required to identify the
device on a network.
You can find on the back side of the Ekinox 2 a laser printed label that hold all these identification
information. This label also includes a data-matrix code that encodes the device unique serial number.
In addition, the Ekinox 2 packaging includes a second label that provides other useful information such as
installed firmware version or GNSS options in the case of an EKINOX2-D.
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Figure 3.2: Ekinox device label sample Figure 3.1: Ekinox2 packaging label sample
EKINOX Subsea Motion Reference Unit
Made in France
Product code
Serial Number
MAC Address
EKINOX-M-G4A1-PS-ES-I1
024000000
98:5C:93:00:00:00
:
:
:

EKINOX 2 Subsea – Hardware Manual EKINOX2SU SEAHM.1.2
3.2. EKINOX 2 Subsea EL mechanical outline (200 m)
All dimensions are in mm.
3.2.1. Front view
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120
138,85
5
119,20
9,20
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EKINOX 2 Subsea – Hardware Manual EKINOX2SU SEAHM.1.2
3.2.2. Top view
3.2.3. ottom view
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70
89
109
87
4 HOLES 5,50
89 70
12
6
4 H8 2,5
4 H8 2,5
36 ±0,025
72
9,20
24

EKINOX 2 Subsea – Hardware Manual EKINOX2SU SEAHM.1.2
3.3. EKINOX2 Subsea ED mechanical outline (6 000 m)
All dimensions are in mm.
3.3.1. Front view
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154,85
136
5
135,20
36,20
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EKINOX 2 Subsea – Hardware Manual EKINOX2SU SEAHM.1.2
3.3.2. Top view
3.3.3. ottom view
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75
75 94
94
92
116 4 HOLES 5,50
14,50
36 ±0,03
6
4 H8 2,5
4 H8 2,5
72
24
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EKINOX 2 Subsea – Hardware Manual EKINOX2SU SEAHM.1.2
4. Electrical specifications
4.1. Main connector
The main Ekinox Subsea connector, located on the top of the enclosure, is an underwater electrical dry-mate
SEACON 37 ways MINI-CON connector. The exact reference is MINM37#22-FCR-Ti.
It is manufactured from Titanium Ti6Al4V and withstands up to 20000 PSI, thus exceeding the pressure
rating of the enclosure for all its variants. The following diagram shows the pin-out definition for the Ekinox
Subsea connector.
4.1.1. Main connector pin out
Pin # Name Remarks
1 Port A - RS-422 - Tx+ Port A serial output RS-422
2 Port A - RS-232/RS-422 - Tx- Port A serial output RS-232/RS-422
3 Port - RS-232/RS-422 - Rx+ Port serial input RS-232/RS-422
4 Port - RS-422 - Rx- Port serial input RS-422
5 Ethernet Rx+ White/Orange RJ45 pin# 3
6 Ethernet Rx- Orange RJ45 pin# 6
7 NC Not connected
8 Port C - RS-422 - Tx+ Port C serial output RS-422
9 Port C - RS-232/RS-422 - Tx- Port C serial output RS-232/RS-422
10 Ethernet Tx+ White/Green RJ45 pin#1
11 Ethernet Tx- Green RJ45 pin#2
12 Port A - RS-232/RS-422 - Rx+ Port A serial input RS-232/RS-422
13 Port A - RS-422 - Rx- Port A serial input RS-422
14 Port C - RS-232/RS-422 - Rx+ Port C serial input RS-232/RS-422
15 Port C - RS-422 - Rx- Port C serial input RS-422
16 VDD_PWR Positive power supply
17 Sync In D Synchronization input signal D
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Figure 4.1: MINM37#22-FCR pin numbering
12 3
5
4
6 7 8 9
10 11 12 13 14 15
16 17 18 19 20 21 22
23 24 25 26 27 28
29 30 31 32 33
34 35 36 37

EKINOX 2 Subsea – Hardware Manual EKINOX2SU SEAHM.1.2
Pin # Name Remarks
18 GND Data Ground return
19 NC Not connected
20 Port - RS-422 - Tx+ Port serial output RS-422
21 Port - RS-232/RS-422 - Tx- Port serial output RS-232/RS-422
22 GND_PWR Power Supply Ground return
23 Sync In Synchronization input signal
24 GND Data Ground return
25 Port D - RS-232/RS-422 - Rx+ Port D serial input RS-232/RS-422
26 Port D - RS-422 - Rx- Port D serial input RS-422
27 Sync Out Synchronization output signal
28 GND Data Ground return
29 Sync In A Synchronization input signal A
30 GND Data Ground return
31 NC Not connected
32 Port E - RS-232/RS-422 - Rx+ Port E serial input RS-232/RS-422
33 Port E - RS-422 - Rx- Port E serial input RS-422
34 Sync In E Synchronization input signal E
35 GND Data Ground return
36 Sync Out A Synchronization output signal A
37 GND Data Ground return
Note: Unlike the Ekinox surface version the subsea one doesn't provide Sync In C signal. However,
please keep in mind that the synchronization input signals are not hard linked to a serial port.
Note 2: The enclosure is isolated from the electrical grounds. The power and data ground are
internally connected but their pinout must be respected for forward compatibility
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EKINOX 2 Subsea – Hardware Manual EKINOX2SU SEAHM.1.2
4.2. Electrical specifications
Electrical specifications from -20°C to 60°C.
Parameter Conditions Min. Typ. Max. Units
Power supply
Operating voltage 9 12 36 VDC
Power consumption 3 W
Allowable Input Voltage Ripple 400 mV p-p
Under voltage lock out Turn on threshold 8,5 V
Turn off threshold 7,5 V
Galvanic Isolation 200 VDC
Sync Out A, Sync Out
Output Type Open-Drain -
High-level Input Voltage 25 V
Low-level Output Voltage 0,25 0,4 V
Low-level Output Current 40 mA
Port A, , C, D, E – RS-232 Receivers, Sync In A, , D, E
Input Voltage Range -25 +25 V
Input Threshold Threshold Low 0,8 1,5 V
Threshold High 1,8 2,7 V
Input Resistance 3 5 7 kΩ
PORT A, , C – RS-232 – Transmitters
Output Voltage Swing Tx loaded with 3kΩ to GND_MAIN ±5 ±5,4 V
Port A, , C, D, E – RS-422 – Receiver
Input Resistance -7V < Common Mode Voltage < +12V 96 kΩ
Input Differential Threshold -7V < Common Mode Voltage < +12V -200 -50 mV
Input Hysteresis 30 mV
PORT A, , C – RS-422 – Transmitter
Differential Output Voltage 2 V
Common-Mode Output Voltage 3 V
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EKINOX 2 Subsea – Hardware Manual EKINOX2SU SEAHM.1.2
4.3. Typical wiring
In this section, we briefly describe a few recommended wiring diagrams.
4.3.1. RS-232 basic communications
elow is shown the main interface (Port A) connection, using a full duplex RS-232 connection using the
standard cable provided with the Ekinox Subsea. See section Appendix A: Ordering codes and Accessories
for more details about this cable.
4.3.2. RS-422 basic communication
elow is shown the main interface (Port A) connection, using a full duplex RS-422 connection using the
standard cable provided with the Ekinox Subsea. See section Appendix A: Ordering codes and Accessories
for more details about this cable.
Note the termination resistors (Usually 120 ohms) that can optionally be placed on receiver side to avoid
communication errors in long distance communications. These resistors can be omitted in short distance
communications in order to reduce power consumption.
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Figure 4.2: Main serial interface full duplex connection in RS-232
Ekinox
GND
PORT A Tx
PORT A Rx
PC
PC Tx
PC Rx
GND
Figure 4.3: Main serial interface full duplex connection in RS-422 mode
R2
R1
Ekinox PC
GND
PORT A Tx+
PORT A Tx-
PORT A Rx+
PORT A Rx-
PC Rx-
PC Rx+
GND
PC Tx-
PC Tx+
R1 and R2 are optional. Recommended
for long distance communication

EKINOX 2 Subsea – Hardware Manual EKINOX2SU SEAHM.1.2
4.3.3. GNSS connection in RS-232 mode
For this typical connection, a shielded AWG 26 cable should be used. Depending on PPS signal strength, we
do not recommend this cable to measure more than a few meters. For long distance, PPS signal and GPS
NMEA signals should be separated in two cables for better noise immunity.
4.3.4. Triggering external devices with the sync Out
Consider a camera that must take a picture when an event is provided on Event Out pin. Event Out and Sync
Out are “open drain” outputs, which means a pull up resistor must be used on receiver side, as shown on the
diagram.
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Figure 4.4: Typical wiring diagram for Ekinox M / U with external GNSS receiver
Ekinox
GND
PORT Sync
PORT Rx
GPS
GPS Tx
PPS
GND
Figure 4.5: Sync Out connection with pull up resistor
Ekinox
GND
Event Out
Camera
Event In
GND
R
VCC < 20V
Pull up resistor must be connected
to Event Out to define High level