Neptune Sonar have recently commissioned a third generation, open-water Acoustic Calibration Laboratory at their Kelk Lake Site in East Yorkshire.

The largest privately owned laboratory of its type in the UK it is equipped with the most technically advanced instrumentation and software providing engineers and scientists with the ability to perform accurate underwater measurements on a wide range of underwater acoustic equipment.

Available to hire, manufacturers and end-users alike will find the facility invaluable whether calibrating a single hydrophone or establishing the underwater performance of a complex sonar system.

Download Brochure – Calibration Facilities

The 17m by 10m floating platform carries two measurement laboratories connected to the shore by a 40m long gangway. The ease of access provided by this gangway offers significant benefits over the use of boats by simplifying the movement and deployment of heavy equipment, reducing Health and Safety risks.

The Laboratory includes the following facilities:

• 60,000 square metre fresh water lake, 10m depth.
• 17m x 10m raft platform, with 4.9m x 2.3m moon pool.
• Direct access via 40m x 2m wide gangway.
• Frequency range from less than 1kHz to 1MHz
• A wide range of calibrated reference Hydrophones and Projectors.
• All measurement certificates fully traceable to National Standards.
• Simulated depth, using submersible GRP acoustic pressure vessel
• Power Supply 20 amp 3 phase 50Hz.
• Cranes and handling equipment, capable of deploying transducers up to 2000Kg.
• Site security approved by the UK Ministry of Defence.
• Other facilities include R&D lab, machine shop, pressure vessels and storage area.
• Telephone, fax, email and internet access.
• Quiet rural surroundings.
• Car park for direct access to facility.

The laboratory is ISO 9001-2008 certified. All the Reference Standards are regularly calibrated in-house using the Reciprocity/ Trimetric method and regularly certified to National Standards.

This is carried out at various times throughout the year to compensate for water temperature variations. All uncertainty calculations are performed by the laboratory’s bespoke software for each discreet frequency.

The laboratory is capable of performing the following measurements:

• Complex Impedance / Admittance
  Fully automated test presenting Polar, Cartesian and Numerical formats.
• Beam Pattern
  In either Transmit or Receive mode, automatic indication of –3dB, –10dB and sidelobe levels.
• Sound Pressure Levels
  Fully automated Receive and Transmit Sensitivity and Source Level Measurements, presenting Linear, Log and Numerical formats.
• Phase and Time
  For sensors and / or systems where bearing and time accuracies are required.
• Simulated Depth Measurements
  A submersible GRP pressure pot designed to simulate acoustic performance and calibration measurements down to depths of 650 metres.

Transmit Sensitivity Graph

Receive Sensitivity Graph

Circle Plot

Beam Pattern

Admittance Plot