Datum Electronics

Torsionmeters and Shaft Power Meters

Datum Electronics is a world-leading supplier of torsionmeters and shaft power meters for the marine industry. Our competitively priced, flexible systems measure the on-shaft torque and shaft power of a ship's drive shaft, capable of measuring shafts with 150mm-1,100mm diameter.

We supply to a range of high-profile clients including the Royal Navy, having installed 15 torsionmeter systems on their Sandown and Hunt class ships. These needed to meet the most stringent test requirements regarding electromagnetic radiation due to their application on minehunters. We are constantly working to develop systems to meet the challenges of both the civilian and military sectors.

Commercial marine torsionmeter

The Datum Electronics commercial marine torsionmeter has been developed to meet the requirements of marine industry customers to provide power monitoring data on ships, to aid fuel economy and equipment maintenance planning.

Robust, permanent and simple to install, the commercial marine torsionmeter accurately monitors the efficiency and performance of the ship's transmission systems, leading to large savings on running costs.

Monitoring actual power levels provides an accurate reference point in assessing:

  • Propeller condition
  • Hull condition
  • Ship condition changes
  • Engine performance monitoring
  • Specific fuel consumption
  • Operational efficiency planning

This tool will measure on-shaft torque, shaft rotation speed and the power going through the shaft. The stator uses a single-point design and does not require mounting around the shaft, allowing for a fast, simple and less intrusive installation compared with conventional designs.

The system can be used on shafts of 150mm-1,100mm diameter, with rotational speeds of up to 900rpm. Standard output is RS485, but this can be upgraded to USB, ModBus, Ethernet, RS232 and analogues (0-10V/4-20mA). In addition, it can be used with our display panel for either single or dual-shaft applications.

Shaft power measurement kit

The Datum Electronics torque trials kit measures the on-shaft torque for trials applications on rotating shafts of 30mm-1,100mm diameter. Whether used for the simple testing of power levels or as a key tool in extended trials to assess fuel efficiency, the series 430 kit is easy to install, test and operate.

The system logs directly on to a PC or laptop with the aid of its software disk. Other advantages include:

  • Portable and lightweight design
  • User-friendly software
  • Easy to install with a step-by-step guide
  • Measuring shaft power, torque and speed as a basic function
  • Logs, records and displays 'real time' data
  • Compatible with two data channels and shaft speed

As well as measuring torque, the instrumentation can be used to verify power outputs from engines and motors, as well as analysing other types of data, including:

  • Power transmission
  • Shaft vibration
  • Vibration and torsional acceleration
  • Torque trials
  • Peak torque levels
  • Power delivery
  • Power transients

Marine torsionmeter system

The Datum Electronics marine torsionmeter system assesses and monitors propeller shafts on ships, by measuring shaft speed, power and torque. Originally designed for use by the Royal Navy, later variations have been provided for the Indian Navy, Australian Navy and Korean Navy.

This means that the system has been through rigorous MOD and MIL testing programmes, and is therefore verified in a number of marine conditions, including:

  • Shock and vibration
  • Heat and humidity
  • Water ingress
  • Salt atmosphere

The series 420 torsionmeter system can be configured for single-shaft or multiple-shaft use, in order to provide accurate non-contact shaft measurement. A fitted shaft unit measures torsional strain and rotational speed, with a separate stator unit to transmit the data to the control unit.

This system fits shafts of 160mm-1,100mm diameter, with stator housings manufactured for a range of shaft sizes:

  • Size 1: shafts 160mm-250mm
  • Size 2: shafts 250mm-350mm
  • Size 3: shafts 350mm-500mm
  • Size 4: shafts 500mm-650mm
  • Size 5: shafts 640mm-800mm
  • Size 6: shafts 800mm-1,100mm

Installation, training and consultancy

All of our systems are supplied along with the required product information and user handbooks. Full training can be provided, either on-site by one of our installation engineers or at our specialist facility in the UK.

Datum Electronics has expertise in a range of fields including electronics, vibration, field testing, strain gauging and installation. Contact us with your problem and we will endeavour to find a workable solution for you.


Contact Details

Datum Electronics Ltd
Needles Building
Trinity Wharf
East Cowes
PO32 6RF
Isle of Wight
United Kingdom
+44 1983 28 28 34
+44 1983 28 28 35

Available White Papers


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