Power take-off torque monitoring.

AIM – Precisely & Quickly Monitor Power Take-Off Torque on A Wave Energy Converter

Challenge
As part of a project funded by Wave Energy Scotland, 4c Engineering needed to test various configurations of the SeaPower Platform, a Wave Energy Converter (WEC), to determine the effects on power capture.   To do this they needed a reliable and accurate way of measuring power take-off (PTO) torque, forces, positions and pressures of the waves on the SeaPower Platform.

Why? Establishing the most efficient design with the highest wave power generation, will make it a more cost-efficient form of wave energy.

The SeaPower Platform extracts energy from deep water ocean waves by reacting to long prevailing wavelengths in high resource sites.

Solution – Accurate DTD-P Parallel Shaft Reaction Torque Transducer
“We chose the DTD-P torque transducer for its high accuracy and compact size which we needed for tank testing the SeaPower Platform,” explains Andy Hall, Director at 4c Engineering.

• Designed for In-Line Static or Semi-Rotary Torque Measurement
• Capacities: 0-10Nm to 0-10kNm
• High Accuracy – Ideal for Calibration, Development and Testing Applications
• Accuracy: <±0.15% / Full Scale Output
• Customised Capacities, Shaft and Configuration Options Available
• IP67 Waterproof and IP68 Fully Submersible Versions Available

Complete Torque Monitoring System
Applied Measurements Ltd provided 4c Engineering with a DTD-P 100Nm parallel shaft torque sensor fitted with an ICA4H miniature load cell amplifier, calibrated to UKAS traceable standards and sealed to IP68 to allow complete submersion. This complete torque measuring system enabled their engineers to reliably and accurately monitor the torque applied by the WEC as it responded to waves in the test tank.

Save on Installation Time
The DTD-P torque transducer has keyed parallel shaft connections for in-line static or semi-rotary torque measurement in capacities from 0-10Nm up to 0-10kNm (custom capacities readily available). This version was fitted with a flying lead, however versions with an integral bayonet lock military connector are also available which promise simple and easy connection.

Guaranteed High Accuracy
The DTD-P torque transducer is highly accurate to better than ±0.15% (typically ±0.05%) of the full scale output, making it ideal for this high precision development and testing application. Additional applications include the testing of electrical motors, hydraulic pumps, automotive transmissions, steering systems and aircraft actuators.

Need a Specific Design?
The DTD-P torque transducer can be customised with bespoke shaft, configuration options and capacities (to 50kNm+) specific to your application. For 4c Engineering we customised the design of the DTD-P torque transducer to IP68 submersible for continuous use underwater to 1m, which was essential for use in the wave test tank.

High Stability, Fast Response, ICA4H Miniature Load Cell Amplifier
“The high speed, reliability and clean output of the ICA4H miniature amplifier enabled the data to be analysed immediately after each test.” says Andy Hall.

• Very Compact 19mm Diameter
• Low Current Consumption
• High Speed 1kHz Bandwidth (max.)
• 4-20mA (3-wire) Output (10 to 30Vdc supply)

Very Compact
To deliver a conditioned load cell output signal we supplied the DTD-P torque transducer with an ICA4H high performance miniature load cell amplifier. The ICA miniature load cell amplifiers are very compact at only 19mm in diameter allowing them to fit inside the body of most load cells. In this application the ICA4H was supplied in a gel filled IP68 immersion protected compact enclosure (see image above) along with 10 metres of cable making it suitable for this underwater application.

With High Speed Response
The engineers at 4c Engineering needed to have a quick and reliable way to process the power take-off torque data from the tests, to determine the power capture and effects of the control settings before running the next test. The ICA4H miniature load cell amplifier was chosen not only for its high stability and compact size but also for its 1000Hz fast response.

A sea platform off the Galway (Ireland) Coast – not far from the Read-out offices.

@AppMeas @4c_Eng #power #PAuto

Ensuring accurate pigment dispensing.

PD Edenhall Ltd is one of the largest independent concrete facing brick manufacturers in Britain. They needed to accurately monitor the quantity of pigment being dispensed into the weigh hopper throughout the manufacture of concrete facing bricks.

Precise pigment dispensing needs to be calculated as inaccurate amounts of pigment can lead to incorrect colour blends, resulting in a loss of sales and profit.

Solution – Accurate DBBSM S-Beam Load Cells and Intuitive4-L Digital Indicator
To monitor the quantity of pigment going into the blend, 3x DBBSM S-beam load cells were connected together to the supports of the pigment weigh hopper.  The DBBSM S-beam load cells checked the load of the pigment weigh hopper throughout the pigment dispensing process and the outputs of the load cells were sent to an Intuitive4 load cell digital indicator.  This enabled the engineers to constantly check the correct amount of pigment was being dispensed into the mix.

“We chose Applied Measurements’ DBBSM s-beam load cells as the pigment is £1000 per tonne so has to be extremely accurate.” Paul Akers, Works Manager at PD Edenhall Ltd told us.

DBBSM S-Beam Load Cells

• Capacities: 0-1kg up to 0-30,000kg
• Force & Load Measuring
• Tension & Compression
• Output: 2mV/V to 2.7mV/V
• High Accuracy: <±0.03% Rated Capacity
• Custom Versions Available
• Fast and Simple to Install

The DBBSM S-beam load cells were ideal to use in this application as they are extremely accurate of better than ±0.03% of the rated capacity.  Coupled with their dual bending beam design, they guarantee excellent accuracy.  Improved accuracy can be further guaranteed by using our specially designed rod end bearings to help reduce any extraneous forces.

They offer an optional sealing to provide protection in the dusty environment and a robust 4-core polyurethane cable, making them ideal to use in the pigment dispensing machine.

Intuitive4-L Load Cell Digital Indicator

• 6-Digit LED Display (±199999)
• Modular Construction
• Fast & Simple to Setup
• Ideal for Harsh Environments – Dust Tight IP65 Protection (Once Installed)
• Superior Accuracy – 10 Point Linearisation
• Higher Stability – Signal Filtering Adjustment
• Improved Resolution – 20-bit A/D Converter
• Compatible with the INT2 Series
• 10Vdc Load Cell Excitation @ 120mA max.
• Powers up to 4x 350Ω Load Cells
• Available in Less Than 1 Week

The Intuitive4-L load cell digital indicator was chosen for this application as superior accuracy was needed due to the high cost of the yellow pigment.  The intuitive4-L boasts a 10 point linearisation guaranteeing outstanding accuracy coupled with a 20-bit A/D converter for high resolution.  High stability is promised with signal filtering adjustment options which reduce the effect of noise or instability of the input signal.  Plus, it benefits from an active filter which reduces the effects of vibration and other external sources of system noise.

The intuitive4-L load cell digital indicator is fast and simple to setup with its single layer menu making the options easier to find.  Dimensions and fittings are entirely compatible with the existing Intuitive2 models making the switch over to this new improved version even easier.

Once installed the intuitive4-L load cell digital indicator has an IP65 dust tight protection rating making it ideal to use in this harsh construction environment.  If that’s not enough we can also provide an optional waterproof front panel cover for that extra level of protection.

The intuitive4-L digital panel meter has a modular construction meaning that PD Edenhall Ltd could configure it to their exact specification saving them money.  Options available include voltage or current analogue outputs, 2 or 4 alarm relays and a serial data output in one of several formats including RS232 ASCII, RS485 ASCII and RS485 ModBus RTU, making this a truly flexible load cell digital indicator.

@AppMeas #PAuto @EdenhallUK

Creating 1000 times more power with submersible load measuring pins.

“Our DBEP load measuring pins and DSCC pancake load cells were ideal to use in this marine application, as both can be readily customised, including dimensions and IP ratings, to make them fully submersible” says Ollie Morcom, Sales Director of Applied Measurements Ltd.

Ocean and tidal currents are a sustainable and reliable energy system. Minesto’s award winning product Deep Green converts tidal and ocean currents into electricity with minimal visual and environmental impact. Minesto’s Deep Green power plant is the only marine power plant that operates cost efficiently in areas with low velocity currents.

Pre-assembly of DBEP pin on Deep Green

DBEP Load Pin
• Fully Customisable
• IP68 to Depths of 6500 Metres Available!
• Stainless Steel – Ideal for Marine Applications
Minesto needed to measure the strut force in Deep Green’s kite assembly. The measuring device needed to withstand permanent underwater submersion. “Our load measuring pin’s stainless steel construction and ability to be customised to IP68 submersion rating made this the ideal choice for use in Deep Green’s control system”, explains Ollie Morcom, Applied Measurements’ Sales Director. Their 17-4 PH stainless steel construction makes them perfect for marine and seawater applications. The DBEP load measuring pin was modified to have an IP68 protection rating to a depth of 30 metres and was fitted with a polyurethane (PUR) submersible cable and cable gland, ensuring the entire measuring system was suitable for this underwater marine application.

The load measuring pin needed to fit within Deep Green’s control measuring system. The load measuring pin’s dimensions can be customised to suit a specific design. As Deep Green needed to retain its small and lightweight construction, the DBEP load measuring pin was manufactured to their exact dimensions, ensuring that it fitted within the control assembly without adding unnecessary additional weight to the structure, thus maintaining the efficiency of the Deep Green kite.

What is Deep Green?
Deep Green is an underwater kite assembly with a wing and a turbine, attached by a tether to a fixed point on the ocean bed. As the water flows over the kite’s wing, the lift force from the water current pushes the kite forward. The rudder steers the kite in a figure of 8 trajectory enabling Deep Green to reach a velocity 10 times faster than the water current, generating 1000 times more power. As the water flows through the turbine, electricity is produced in the gearless generator. The electricity is transmitted through the cable in the tether and along subsea cables on the seabed to the shore. Customised versions of our DBEP load measuring pins and DSCC pancake load cells are used within the control system of the kite.

DSCC Pancake Cell

DSCC Pancake Load Cell
• Fully Customisable
• Low Physical Height
•Optional: IP67, IP68 and Fatigue Rated Versions Available
• High Accuracy: <±0.05%/RC
Minesto also needed to monitor the varying tension load of the tether created by the wing. Using our high accuracy DSCC pancake load cells we were again able to make a custom design to fit into their existing assembly. Our pancake load cells are also manufactured from stainless steel and can be modified with alternative threads, custom dimensions, mounting holes, higher capacities and higher protection ratings. The DSCC pancake load cell used in Minesto’s marine power plant was IP68 rated for permanent submersion in seawater to 50 metres depth. The pancake load cells design delivers excellent resistance to bending, side and torsional forces and its low profile makes it ideal where a low physical height is required.

ICA2H Miniature Load Cell Amplifier
Within the pancake load cell we fitted a high performance ICA2H miniature load cell amplifier. The ICA2H miniature amplifier is only Ø19.5mm and 7.6mm high and is designed to fit inside a broad range of strain gauge load cells where a larger amplifier cannot. It has a low current consumption and delivers a 0.1 to 5Vdc high stability output. Using an integrated miniature amplifier kept Deep Green’s control assembly small and lightweight. The ICA2H miniature amplifier was chosen because of its high stability and fast response which is essential for the safe and efficient operation of Deep Green.

“We really enjoyed working with Minesto on this fantastic marine project.”

@AppMeas #PAuto #Power

Complete Tensile Monitoring System Delivered in Under 1 Week.

“We can deliver a complete tensile monitoring system in under 1 week! Don’t take our word for it, take Clark Masts’!”

Challenge – To Measure Larger Loads in Stainless Steel Guy Cables with a Super-Fast Delivery.

Clark Masts, a telescopic and sectional mast manufacturer, needed a way to accurately monitor the tensile stress in the guy cables of their newly developed super-heavy telescopic masts and they needed it urgently.

With head loads of up to 500kg and extended heights of up to 34m, the measuring instrument needed to accurately handle the larger head loads, taller heights AND be delivered in under 1 week!

“For our new larger mast range with large head loads we needed an instrument with a higher range up to 500kg and in a hurry, so that’s how we decided upon your product.” Gwyn Evans, Clark Masts Systems Limited. Here’s the story.

DBBSM S-beam load cell and TR150 handheld indicator make a fast & accurate tensile monitoring system.

DBBSM S-Beam Load Cell to the Rescue!!

• Capacities: 0-1kg up to 0-30,000kg
• Output: 2mV/V to 2.7mV/V
• High Accuracy: <±0.03%
• Customised Versions Available
• Rod End Bearings & Load Buttons Available
• Delivery Under 1 Week!

Tensile strength on guys

With huge capacities of up to 30,000kg and an accuracy of <±0.03% of the rated capacity, the highly accurate DBBSM S-beam load cell really is the knight in stainless steel armour. Not only can it efficiently handle the larger loads in the guys, it can also be supplied in less than 1 week! Its tough construction makes it ideal to use in the harsh outdoor conditions on the guy cables.

Rod Ends and Mounting Accessories
Clark Masts were supplied with a DBBSM-1000kg S-beam load cell and additional rod end bearings to enable effective tensile testing of the larger loads in the guy cables. The rod end bearings serve to:

• Centralise the Tensile Force Through the Primary Axis.
• Reduce any Extraneous Forces.
• Improve Overall Performance and Accuracy of the Load Cell.

“By using the DBBSM S-beam load cell with the rod end bearings, Clark Masts increased the overall efficiency of their tensile monitoring system.” said Robert Davies, Applied Measurements‘ Production Director.

TR150 Handheld Display
Along with the DBBSM-1000kg s-beam load cell they also supplied a 7 digit LCD handheld indicator. The TR150 handheld indicator has an IP65 rating making it a perfect partner to the DBBSM S-beam load cell, as both can be used in the harsh outdoor environments of Clark Masts tensile testing. Its dual range function means the display can be calibrated in 2 different engineering units i.e. newtons and kg or can be used to calibrate 2 separate load cells using just 1 display. It is powered by 2x AA batteries which can last up to 450 hours of continuous use in low power mode.

Their DBBSM S-beam load cell can be supplied in less than 1 week and with our ex-stock TR150 handheld indicators mean we can offer a complete tensile monitoring system in under 1 week!

@AppMeas #Pauto

Pressure Transducer Delivers water level monitoring in emergency tank shower!

Applied Measurements were recently contacted by spill control and containment manufacturer Empteezy, to provide a sensor to be used within an emergency tank shower.  The emergency tank shower is ideal for use in locations where a constant water supply and adequate water pressure cannot be guaranteed.

The Challenge 
To ensure the emergency tank shower is able to provide a flow of 75.7ltrs per minute of water for 15 minutes, fulfilling the ANSI Z358.1 regulations for emergency tank showers.

The Problem 
Once a gravity fed shower is switched on and the water level within the tank drops, both the water pressure and the flow rate at the shower head decreases.  In order to achieve the flow rate of 75.7ltrs per minute of water for the full 15 minutes, the emergency tank shower needs to contain a minimum of 2000ltrs of water within the tank.

The Solution
Applied Measurements provided Empteezy with a Pi600 series pressure transducer.  The pressure transducer was connected and calibrated to the digital readout scale on the front of the shower, giving an accurate reading of the litres of water remaining in the tank.  When the water level falls below the minimum safety level, a signal is sent to the sounder strobe alarm on the front of the shower.  This signal has a dual function. Firstly, alerting safety personnel that the water level has dropped below the minimum, notifying them to refill the shower to achieve the required flow rate and water pressure. Secondly, that the shower has been operated and an injured employee may need assistance.

The Pi600 Series of Pressure Transducers
The Pi600 series of pressure sensors are designed for the measurement of gas and liquid pressure across a wide range of general purpose and industrial applications such as hydraulics, medical, research and development, meteorology and food processing.  Constructed from stainless steel with a ceramic diaphragm and viton ‘O’ ring seal as standard, they are designed to be extremely rugged, yet compact in design.

Key Features Include:

• Ranges 0-50mbar up to 0-700bar
• Wide Variety of Outputs: mV/ Volts / mA
• Can be Offered Calibrated in Metres Water Gauge
• Sealed to IP65 (plug & socket) or IP66/68 (Cable)
• Accuracy: <±0.25%/FS (0.1% option)
• Gauge or Absolute Versions
• Various Pressure Port Options (G1/4” male as standard)
• Excellent Chemical and Abrasion Resistance
• Rugged Construction
• Full Customisation Possible

These pressure transducers come in pressure ranges of 0-50mbar and 0-700bar in absolute or gauge versions, with a wide choice of electrical output signals from its ASIC-based amplifier circuit.  These outputs include, 4-20mA, 0-5Vdc & 0-10Vdc, 1-6Vdc and 10mV/V, as well as a ratiometric 0.5-4.5Vdc signal that requires a 5Vdc supply to suit most data loggers.  The Pi600 series of pressure transducers can also be supplied with any of our wide range of instrumentation to give you a complete calibrated system.

In addition, the series can be completely customised to suit your application including; custom process connections, alternate case and ‘O’ ring material for applications where aggressive media is present, and higher IP ratings for more challenging environments.

The Pi600 series of pressure transducers have proved vital in Empteezy’s emergency tank shower units, enabling engineers to guarantee the water pressure and flow rate of the units.  We are always looking for new and exciting challenges so contact our technical sales team today on +44 (0) 118 981 7339 or info@appmeas.co.uk to discuss your application.

Telemetry Lift Link Load Cells Tip the Scales for Plaxton Bus.

The Challenge – To Measure the Centre of Mass of a Coach or a Bus.

Applied Measurements were recently commissioned by bus and coach manufacturer Plaxton, (part of the Alexander Dennis group), to design and manufacture a system for measuring the centre of mass of a bus. Determining this factor is a critical part of vehicle design and engineering, ensuring that buses and coaches have the ultimate levels of stability while in motion.

Zoom-in on sensor!

The Solution – the ET24 Wireless Telemetry Load Cell.
The ET24 telemetry load cell is designed for under hook and lifting gear weighing applications and can be used with any standard lifting shackles. These wireless telemetry systems can be used as a single-channel set-up, using one sensor and display, or for multiple load cells in a single application.

In the case of Plaxton, a multi-channel system was set up using two ET24-5T and two ET24-12T telemetry lift link load cells, two inclinometers (angle sensors) and a T24-BSu base station. ET24 telemetry load cells were attached to each corner of the bus to monitor the load and the two inclinometers were used to measure the incline. Once the bus was lifted, instantaneous measurements were picked-up by a T24-BSu wireless telemetry base station and the data was transmitted straight to the PC or laptop.

The T24-BSu USB Base Station
The T24-BSu USB base station receives the data from the telemetry load cells and relays it to a PC or laptop via the USB port. This simple USB connection means no additional wires are required as the power supply is drawn directly from the USB port. The T24-BSu base station configures the telemetry system using the free user-friendly downloadable T24 Toolkit software, which offers basic logging to excel.

As Plaxton required readings from multiple telemetry load cells, their system was configured using T24Log24 software. The T24Log24 software enabled engineers to view and log up to 24 channels of data simultaneously throughout the test and made it possible for Plaxton to analyse the information later.

Multiple ET24 telemetry load cells can be used in a single application.

Benefits of Using the ET24 Wireless Telemetry System

• Wireless transmission up to 200 metres – no cables required
• Use multiple load cells in a single application
• Immediate simultaneous readings
• High accuracy outputs +/- 0.3% of reading
• Free user-friendly T24 software allows the user to view, log and download the data to csv file for manipulation in excel
• Easy USB connection from the T24-BSu base station to the PC or Laptop

The ET24 telemetry load cell can be supplied on short delivery (2/3 weeks) and can be pre-calibrated with various receivers.

Non contact measurement in concrete plant

Following a request from a manufacturer of concrete products,  Applied Measurements has developed a user-friendly, low-cost device to rapidly and accurately measure tension in pre-stressed wire and cable.

Applied Measurements Limited offers a comprehensive selection of transducers based on strain gauge technology.  Our product range includes sensors to measure load, pressure, torque and displacement.  In addition, a custom transducer design service and strain gauge bonding facilities are also available.

To support the transducer range, a variety of analogue and digital instrumentation is available including high resolution, high speed and RS232/485 equipped signal conditioners and indicators, as well as portable battery powered indicators with integral data-logging, enabling us to offer complete systems with calibration traceable to UKAS standards.

In addition to our comprehensive range of ‘standard’ transducers, we also have the capability to design, develop and manufacture custom devices to meet specific needs.  Our expertise is based on bonded strain gauge technology, which is carried across our complete line of transducers.  Our involvement in your project can be at any stage, from development and design, through prototypes, testing and into full production.

The Challenge:
To rapidly and accurately measure the tension within pre-stressed steel wire or cable using a repeatable process that will serve to increase the confidence of the end product.  To manufacturers of concrete products, the ability to make these measurements using a simple process that removes operator uncertainty from the measurement is paramount.  This was the challenge set to Applied Measurements, by Bison Concrete.

Bison is one of Britain’s leading producers of structural, pre-cast concrete products. Consistent, quality control is vital to maintain the company’s position at the forefront of the sector.  The company is particularly renowned for pre-stressed elements, including hollow-core floors, solid composite floors and beams.

This development was prompted by a customer asking for a non-contact method for determining the tension in reinforcing cables and bars for pre-stressed concrete beams.  Peter Lewis, the managing director of Applied Measurements investigated the dynamics of the measurement and discovered that a vibrating steel wire or bar would have on an externally applied transverse magnetic field.

After significant development the ‘Digiforce’ was born and the patented device has now been supplied to many other concrete manufacturers’ including RMC, Concrete, Tarmac, Spiroll Precast, Coltman Precast, Milbank in Britain, Burns in the USA and Impact in Australia – and other blue chip construction companies all who share the need to make rapid and accurate tension measurements on-site.

The Solution:
The equipment used for this tensioning process must be tested on a regular basis, but current methods are cumbersome and time-consuming and accuracy is in part dependent on the skill of the operator.  The Digiforce developed by Applied Measurements has enabled Bison to achieve rapid, repeatable, non-contact tension measurement using cutting-edge technology.

Integral to the durability and structural performance of these products is the correct tensioning of the pre-stressing steel tendons. There are approximately 30 tendons in the average 1200mm-wide hollow-core floor slab, which may be up to 160m in length.  By striking the wire or cable under tension and observing their fundamental natural frequency of vibration, it has proved possible to develop a battery powered hand held instrument capable of accurately determining the tensile forces applied to them.

Although simple in theory, the low frequencies – Hz to a few tens of Hz and complex sound spectra have up to now, prevented their accurate analysis on-site.  The Digiforce addresses this issue via the integral mathematical software, to process only those frequencies of interest that contributes to the measurement.  This means that the user no longer has to refer to look-up charts or return to the office to run complex calculations pertinent to that piece of equipment or installation.

Operation:
The instrument is first programmed with the length of the wire or cable whose tension is to be measured.  Also inputted is its weight per unit length. The magnetic sensor at the end of the instrument is then placed adjacent to the part to be measured. The measurement process is triggered and the part is struck lightly with the mallet supplied. After a few moments, the tension appears on the LCD display on the instrument.

Tensions in stainless steel or other non-ferromagnetic wires can be measured by attaching clips (also supplied) made of ferromagnetic materials, provided that their masses are insignificant compared to that of the cable to be measured.

The vibrations being analysed are complex and the fundamental frequencies that the method uses are in the range 3Hz to 70Hz and not the metallic note heard by the ear.  The tension is determined from the formula, T = 4 x length2 x Hz2 x weight per unit length.  Because of the very low frequencies, tuned circuit filter methods are not an option. Instead, the device makes an initial 20 measurements of each oscillation and discards these. The next five measurements from 10 oscillations are then used to establish a tolerance band to establish which measurements are reasonable to contribute to the calculation and which should be rejected as spurious. Subsequent measurements are then made and those that fall within the tolerance band are used to calculate the final measurement value.

Because the principal business of Applied Measurements is in designing and manufacturing precision load cells and force sensors, the measurements are traceable back to NPL calibration standards.

The Digiforce boasts an on-board data-logging facility for collecting results and an RS232 port / USB converter for later downloads to a host PC, driver software, aluminium striker, rugged carrying case and full instructions.  Additionally the device is supplied with a 3-year warranty.

Following the success of the Digiforce in pre-stressed concrete, other applications are now being realised.  One such success story is Stage Technologies in London, who use the product to monitor the loading on cables used to support various stage elements.