AQUAlogger® 540

Temperature, pressure - to 4000m

Ideal for deep water research and real-time monitoring

Benefit from immediate temperature and depth readings with the AQUAlogger 540…

…giving accurate results in real-time.

The AQUAlogger® 540 is a self-contained temperature and pressure logger that offers simple data connection, configuration and download, and real-time reporting capability. The versatile instrument is suitable for a wide variety of applications, both ocean and environment. The AQUAlogger® 540 is capable of monitoring in water depths of up to 4000m, making it a suitable choice for many oceanographic research professionals.


  • Deep water temperature distribution surveys
  • Real time oceanographic and environmental monitoring

Personalised research

  • We can provide you with custom solutions for water depths beyond 4000m.
  • If you have a specific project in mind, we can help by setting up a complete real-time monitoring system.

Real-time reporting capability

  • Data can be collected in real-time, providing you with immediate results, available for prompt analysis.
  • Real-time data allows you to respond to temperature and pressure changes immediately.

Reliable sensing

  • Each logger is individually calibrated by our expert team.
  • Aquatec offer an annual service and calibration plan, to ensure continuity of reliable data.
  • The logger can be supplied with depth and temperature sensors, or temperature only, to enhance your understanding of the environment.

Ready to use

  • We supply you with everything you need to get started, including a USB cable, software and manuals.
  • The AQUAlogger 540 is supplied with a spare battery and maintenance kit as standard.

Sensor specification




Sensor type


Piezo-resistive bridge


-2 to 30°C standard, other ranges on request

5 bar (~40m), 11 bar (~100m), 51 bar (~500m), 101 bar (~1000m), 201 bar (~2000m), 401 bar (~4000m)
(Other sensors available on request)


better than 0.007°C

better than 0.01% full scale



typically better than 0.2% full scale

Time constant

better than 5 seconds to 63% of the change in value


Logger specification

Data storage capacity

Greater than 4M parameter readings, in non-volatile FLASH

Logging lifetime

Depends on logging parameters - up to 1 year

Data retention

>10 years

Burst sampling

Bursts every 1 – 255 seconds or 1 – 255 minutes

Within-burst rate

From 1 Hz to once every 30 seconds

Burst averaging

Bursts may be averaged to a single data value


RS232 or RS422 (specify) and USB 1.1, bus powered

Optional extra inputs

2 channels 0-5V external

Optional controls

External trigger input or output


3 x 3.6V Custom Lithium ‘AA’ cell pack


AQUAtalk for Windows for configuration and download


Single attachment through mounting hole or use clamp

Maximum depth

1000m standard version (acetal)
4000m deepwater version (stainless steel)

Q: I need to know the depth in metres.

A: A conversion from pressure to depth is now standard for AQUAlogger® 540 instruments.

Q: Can it provide data in real time?

A: The AQUAlogger® 540 has real time capability as standard. We can provide a range of subsea communication solutions, including cable, optical modems and acoustic modems. Please let us know what you are looking to do and we will help you design your system.

Q: Can we replace the batteries ourselves?

A: The batteries are technician replaceable. A spare battery is supplied with the instrument and further batteries are available on request. Please note, your warranty will be void for leaks if the instrument is opened. A battery change is offered as standard in an annual service.