VESSEL-MOUNTED

09/16/2024

VM Operations - 333 kHz

Assists operators on vessels to make informed decisions during subsea
operations in areas affected by underwater currents

In recent years, offshore operations have moved farther offshore, often into challenging operational environments.
Variable local current and tide patterns make for increased risk, uncertainty, and operational costs. Subsea
operations can be limited by these challenges without real-time knowledge of currents.
Using our renowned Signature ADCP technology, the VM Operations is designed to give offshore operators clearand detailed information on current speed and direction from the vessel to the seafloor. This situational awareness
improves efficiency during vessel time. Data can be stored and analyzed during future project planning.
Read more about the VM Operations capabilities here.

Highlights
Concave transducer design allowing for
flush mounting, independent of salinitychanges
A 333 kHz frequency for an optimal balancein required range, resolution and accuracy
for a wide range of operations at the coastal
continental shelf
Outstanding bottom-track performance,even under challenging conditions
Robust sea valve allows mounting without
increased draft
In-water serviceable, diverless, concept via
the DNV type-approved sea valve
Unique, easy-to-use graphical ADCP
interface for the operator, superintendent orclient

Applications
ROV and diver inspections
Subsea installations (as cable laying or rockdumping)
Towed (seismic) surveys
Aid to navigation
Fuel efficiency monitoringTechnical specifications
Water velocity measurements
Profiling range*

100 m

Cell size

1-6 m

Max no. cells

128

Min. blanking

0.5 m

Minimum accuracy

0.3% of the measured value

Velocity resolution

0.1 cm/s

Maximum sampling rate

2 Hz

No. of beams

4 slanted beams at 25 degrees*) Maximum range depends on acoustic scattering conditions and transmit power

Bottom velocity measurements
Single ping std @ 3 m/s

0.5 cm/s

Long-term accuracy (1)± 0.3 %

Minimum altitude

0.3 m

Maximum altitude (2)150 m

Velocity resolution

0.01 mm/s

Maximum sampling rate

2 Hz

(1) Following standard callibration procedures(2) Bottom-track distance dependent upon bottom type

Other, Vessel Mounted ADCP
Temperature sensor range /accuracy-4 °C to 40 °C / 0.1 °C

Pressure

Piezoresistive

Compass

Solid State magnetometer

Tilt

Solid State accelerometer

AHRS

Attitude sensor (option)

IO

Ethernet (DF21 over serial as option)

DC Input

24 V DC

Operating temperature

0 °C to 40 °C

Storage temperature-20 °C to 60 °C

Depth rating

Bottom track is limited to surface vessels

Mechanical
Instrument materials

POM with Titanium fastener

Instrument weight

7 kg

Installation

Instrument to be flush mounted with hull (sea valve solution)

Sea valve (option)

DNV type approval; TAS00002CU

Sea valve material

Ductile Iron (body), Bronze (seat)Sea valve weight

85 kg

MechanicalBell housing material

Steel DIN17121

Bell housing weight

29 kg

Processing unit
Processor/memory

Intel i5/8 GB

Hard disk

SSD, 256 GB

Operating system

Windows® 10Housing

19" rack-mountable 2 HE

Dimensions

482x87x400 mm

Input

110-240 V AC, 100 W Max

Total weight

7 kg

Connections*Power, Signature ADCP, 2x DisplayPort, 1x LAN, 2x USB, 4x
RS232|RS422|RS485 configurable port**) Processing unit requires heading and GNSS input over Serial or Ethernet

Nortek VM Operations acquisition software
Acquisition input

Signature VM - binary

Configuration

Signature VM ADCP, Alignment offsets, Outputs

Display

Vessel track in map, Bottom-track magnitude, direction anddepth: (SOG), (COG), Speed Through Water (STW), Meanwater column magnitude and direction, 4x depth selectablelayer (magnitude and direction), 3D velocity profile(magnitude and direction), 2D vessel cross track current, 24hmean current and direction history (tides), Notes, Echocorrelation, Echo amplitude

StatusSignature VM BT and VB + NMEA GGA, HDT, VTG

Online output

NMEA data formats or binary AD2CP with embedded NMEA.
DF21 BT proprietary (optional)

Post processing

Signature review software (optional)

Multi vessel display

VM Operations streaming data and display (optional)*Please note that the package includes the VM Operations acquisition software. The post-processing Review
software is optional.