Nortek Signature VM Ocean is a Norwegian vessel-mounted acoustic Doppler current profiler package for large ocean-going research, survey, and operations vessels. Nortek's current product material separates a 100 kHz VM Ocean configuration for upper-ocean current profiling and optional echosounder work from a dual-frequency 75/55 kHz long-range configuration for deeper ocean current profiles.
Nortek's current VM Ocean material presents the family by acoustic-frequency lane: the 100 kHz version emphasizes upper-ocean profiling and optional echosounder work, while the 75/55 kHz version is the long-range ocean-current configuration.
| Variant | Configuration | Designation notes |
|---|---|---|
| Signature VM 100 kHz | Upper-ocean VM Ocean configuration | Official specifications list a 325 m current-profiling range, a 560 x 560 x 300 mm transducer, 1-degree beam width, and optional scientific echosounder use on the vertical beam. Sources: Nortek VM Ocean |
| Signature VM 75/55 kHz | Long-range dual-frequency VM Ocean configuration | Official specifications list 75 kHz and 55 kHz operation, a 1000 m current-profiling range, a 1385 x 1385 x 555 mm transducer, and 1.6-degree beam width. |
VM Ocean sits inside the shipboard ADCP lane, with lower-frequency ocean configurations complementing Nortek's higher-frequency coastal package.
| Compatible item | Item type | Compatibility evidence |
|---|---|---|
 | Current profiling instrument class | Nortek identifies VM Ocean as a vessel-mounted ADCP package for large ocean-going vessels; NOAA describes ADCPs as instruments that use acoustic returns to measure current speed and direction through the water column from shipboard and other platforms. Sources: Nortek VM Ocean, NOAA Ocean Exploration ADCP explainer |
 | Coastal vessel-mounted ADCP package | Nortek's Signature55 VM Ocean update places the long-range 75/55 kHz lane and the 100 kHz VM Ocean option beside the VM Coastal 1000, 500, and 250 kHz package, separating deeper ocean profiling from shorter-range coastal and lower-depth work. Sources: Nortek Signature55 VM Ocean news, Nortek VM Coastal |
VM Ocean is best treated as shipboard measurement support equipment. Nortek describes it as a large-vessel ADCP package for current profiles and, on the 100 kHz configuration, scientific echosounder work; NOAA's ADCP explainer describes the wider shipboard role of measuring current structure while a vessel is underway.
Nortek says the 100 kHz and 75/55 kHz VM Ocean units are typically installed inside the hull or in a lowered hull-attached structure such as an instrument gondola, with configuration options also listing over-the-side, hull-mounted, and USV-mounted setups.
The package feeds onboard acquisition and review software for real-time current velocity display, long-range current speed and direction information, intermediate profiles, and biomass estimates on the 100 kHz echosounder configuration.
No public source checked here tied Signature VM Ocean to a named cataloged vessel or conflict, so the record remains a relationship-only sensor page.
Sources: Nortek VM Ocean; NOAA Ocean Exploration ADCP explainer.
Nortek identifies 1996 as the year the company began developing ocean current-measurement instrumentation.
Sources: Nortek company history
Nortek's company history places the launch of the Signature product series in 2013.
Sources: Nortek company history
Nortek's company history lists the Vessel Mounted series as a 2018 product-line launch.
Sources: Nortek company history
Nortek described a dual-frequency VM Ocean instrument using 55 kHz and 75 kHz profiling to extend vessel-mounted measurements toward 1000 m.
Sources: Nortek Signature55 VM Ocean news
