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How Avtron Dynamometers work PTO input Burden Unit Specification and technical data 1-10 Transportation, Installation, Location Transporting and storing Avtron Dynamometers Lifting by fork lift truck Lifting by crane or hoist Protection and securing on transport Trailer Operation Before Towing...
Table of Contents Choosing and checking the PTO shaft Fitting the PTO shaft Setup for bare Engine Testing Removing the Sigma 50 & 60 Gearbox Starting the Dynamometer 3-14 Hand-held Engine Testing The Sigma Hand-held Controller Updating Hand-held Firmware Using the Hand-held keypad The function keys The quadrant keys The LED status lamp...
Chapter One provides an introduction to the general principles of engine testing and explains how an Avtron dynamometer makes the process easier, safer and more reliable. It then provides an introduction to the dynamometers, explains how they work, and then introduces their main features.
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An Important Note on Safety Avtron dynamometers are designed with safety as a very high priority, but their operation does present some risks. Tractor PTO shafts can be particularly hazardous and you should not use this equipment unless you have read and understood this manual, the PTO shaft manufacturers manual and are familiar with the accepted practice for the industry.
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Chapter One Introducing Avtron Dynamometers If you are not familiar with the use of Avtron dynamometers you should start with this chapter. It provides an introduction to the general principles of agricultural engine testing and then explains how an Avtron dynamometer makes the process easier, safer and more reliable.
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Chapter One Why test tractor engines? The diesel engines fitted to agricultural machines such as tractors are different from those fitted to ordinary vehicles in one very important respect. They often have to operate at full power output for long periods of time. For some applications, such as ploughing, the ability to produce maximum power can be of critical importance.
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Introducing Avtron Dynamometers Introducing Avtron Dynamometers Avtron’s Dynamometers are purpose built for the testing of agricultural engines. They are designed to be connected to the vehicle’s PTO output to allow the power output of engines to be measured quickly and accurately. They are mains powered, air cooled and are capable of handling the full power output of even the largest agricultural engines for extended periods.
Capacities The Froment 515 dynamometer has a maximum capacity of 380 kW (515 PS). It provides an economical option suitable for general use. The Froment 680 dynamometer has a maximum capacity of 500kW (680 PS). This additional capacity means that it can be used to test right through the power curve of the larger tractors on the market today.
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Introducing Avtron Dynamometers Fork Lift Pockets Fixing Point Figure 1-3 Static variant of a Froment 515 or 680 Dynamometer. 1 - 5...
Control Options Avtron dynamometers have two control methods that can be used, depending on the requirement. The Sigma Dynamometer Hand-held. The hand-held has a outdoor rated enclosure with a custom-designed membrane keyboard and 4.3”...
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Introducing Avtron Dynamometers The Hand-held has a simple to follow user interface that allows any of five test modes to be configured and selected. The clear back-lit display provides a live data readout of power, torque and speed measurements during the test.
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Chapter One How Avtron Dynamometers work The dynamometer works by applying a calibrated and controlled braking force to the tractor engine, whilst measuring the speed of the engine’s rotation. Measuring the speed and power under a specific load allows the amount of torque produced by the engine at different speeds to be calculated.
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Introducing Avtron Dynamometers PTO Input The dynamometer design exploits the fact that most tractors and many agricultural machines are fitted with a power take-off shaft. The PTO provides a quick method of connecting the dynamometer to the engine using a drive shaft without the need to remove the engine from the vehicle.
Chapter One Specification and technical data Froment 515 Froment 680 Capacity (PTO Input) Maximum Power 380kW (515 PS) @1000 rpm 500kW (680 PS) @1000 rpm Maximum Torque 3170Nm @800 rpm 4150 Nm @800 rpm Continuous speed 1000rpm 1000rpm Max Overspeed...
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Chapter Two Transportation, Installation, Location Trailer mounted Avtron Dynamometers are designed for mobile operation, and do not require a permanent installation as such. However the characteristics of the site where the unit is to be operated are important for both static and mobile variants, and are similar in...
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Trailer mounted Dynamometer units can be moved from site to site using a standard vehicle mounted towing hitch. The Static variants of the Avtron dynamometers are intended for permanent Note: Ensure that you installation on-site, and are fitted with a base frame which contains fork lift...
There are a number of factors that need to be taken into account to ensure that a trailer mounted Avtron Dynamometer can be used safely, effectively and within the regulations that apply locally. You must check whether you have an appropriate driving licence, and be sure to observe any speed limits that are in force for towing vehicles.
Chapter Two Before towing: 1. Ensure that all opening panels are securely closed and the rear corner props are fully up and locked in place. 2. Check the ball head cup is well greased. 3. Inspect the break-away cable. If it is kinked, frayed or damaged replace it immediately.
Transportation, Installation, Location Dynamometer Installation The trailer mounted versions of the Dynamometer are intended for use as mobile units at temporary locations. As such, no permanent installation is required. However, the environmental and site location requirements, particularly regarding the need to ensure an adequate airflow, are similar for all units. 5m minimum free space 2 metre (minimum) 2 metre (minimum)
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Chapter Two • There must be sufficient ventilation to ensure that the surrounding air temperature does not rise by more than 10°C above ambient during full load operation. • The dynamometer should be mounted in free air with equal pressure at the air inlet and outlet screens when the fan is at rest.
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Transportation, Installation, Location Tractor Standing For a fixed installation, or if regular testing with a trailer mounted unit is to be carried out, we recommend a concrete slab be laid to provide the tractor standing. Hard-core or compacted soil will quickly deteriorate with constant use. To avoid excessive vibration the tractor standing must be level and large enough so that the tractor can stand parallel with the base of the dynamometer.
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Chapter Three Setting up a Tractor Test This chapter explains how to set up the dynamometer with a tractor in preparation for a test. Please pay particular attention to the safety information that appears at the beginning.
Chapter Three About Safety Tractor PTO shafts can be extremely dangerous and dynamometer testing exposes them to very high levels of stress - much higher than they are normally exposed to in day-to-day operation. This means that you should only make use of drive shafts that are in good condition.
Setting up a Tractor Test Setting up a Tractor Test Tractor Position The position of the tractor in respect of the dynamometer is extremely important. 1. Ensure that the tractor PTO output and the input shaft are in line and parallel. Note: Poor positioning of the tractor will cause excessive vibration and...
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Chapter Three Positioning a Trailer Mounted Dynamometer Before testing can begin you must ensure that the tractor standing and test area are suitable for the purpose. The dynamometer and tractor must stand on a level, firm surface with no possibility that the prop stands or jockey wheel will sink into the ground (refer to Chapter Two for details).
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Setting up a Tractor Test Dynamometer Setup Open the control panel door at the end of the dynamometer: 1. Connect the 230V AC supply to the mains input connector. 2. Connect the Hand-held (or PC) cable to the SIGMA control connection points. Main Power Input Stop/Reset Button SIGMA Hand-held...
Chapter Three Tractor Setup The Dynamometer allows you, within the capacity of the dynamometer in use, to apply the full load capability of the tractor on test by pressing a small control key. In many cases the tractors you will test will not have been subjected to such demands of power since manufacture or pre-delivery inspection, when all systems were new.
Setting up a Tractor Test Choosing and Checking the PTO shaft A variety of half drive shafts are stored at the rear of the trailer in storage tubes. The drive shaft consists of a male and female telescopic section fitted with internally splined end yokes supported by needle roller bearings.
Chapter Three Fitting the PTO Shaft The PTO shaft that connects onto the Froment Sigma 680 Gearbox is fitted with a taper pin clamp yoke. This requires that a taper pin bolt be fitted to ensure that it is locked in place on the shaft. The Froment Sigma 515 dynamometer PTO drive shafts are fitted with a quick release collar.
Removing the Froment 515 & 680 Gearbox When driven via the gearbox the Froment 515 & 680 model dynamometers can be used to test engines in the speed range between 270 to 1250 RPM. Removing the gear box and connecting directly to the burden unit input shaft will increase the speed range to between 480 to 2200 RPM.
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Chapter Three 2. Remove the gearbox drive bolt and retainer. 3. Fit the Froment gearbox removal tool and its pressure plate. 3 - 10...
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Setting up a Tractor Test 4. Place a suitably sized wooden block under the gearbox to support it during removal. Fit the removal tool tommy bar, remove the lock pins from the torque arm, and the remove the gearbox torque arm. Warning! Take care whilst handling the gearbox.
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Chapter Three Chapter Three Chapter Three 6. Fit the direct drive shaft to the burden unit’s input shaft. 7. Tighten the four retaining bolts (refer to the manufacturer’s instructions for the correct torque). 3 - 12...
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Setting up a Tractor Test Setting up a Tractor Test Setting up a Tractor Test Re-fitting the gearbox is a reversal of the removal sequence: 1. Remove the four direct drive shaft retaining bolts and remove the direct drive shaft. 2.
Chapter Three Chapter Three Starting the Dynamometer Start the dynamometer with the following procedure: 1. Switch on the mains electrical power to the dynamometer. 2. POWER ON and START indicators on the control panel will light. After a brief self-test the START Indicator will extinguish. 3.
Chapter Four Hand-held Engine Testing This chapter explains how to operate the dynamometer using the Dynamometer Hand-held. If you intend to make use of Avtron’s Dynatest PC software instead, please refer to the online help system provided with the software.
Chapter Four Chapter Four The Sigma Hand-held The SIGMA Hand-held is a rugged controller that provides a simple method of both controlling the dynamometer during testing and of displaying the test results during and after a test. The hand-held has an outdoor rated enclosure with a custom-designed membrane keyboard and 4.3”...
Hand-held Engine Testing Chapter Four Updating Hand-held Firmware Making sure the firmware is up to date on the Sigma Hand-held is important to maximise testing capabilities and ensure correct operation. The Sigma Hand-held has a micro USB port to enable firmware to be updated from a USB flashdrive. The current version of the firmware is displayed on start up in the bottom right corner of the screen.
Chapter Four Using the Hand-held keypad The keypad contains eight membrane switch keys and a single LED indicator. The switches provide four function keys (marked F1 to F4) arranged below the screen and a quadrant of four control keys (labelled O, I, +, and -) arranged around the LED.
Hand-held Engine Testing Using the Hand-held Immediately after the START button on the control panel is pressed the search screen will appear on the Hand-held. After the search is complete the current screen will be displayed. Note: The software version number is displayed on the search screen.
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Chapter Four Torque %. The percentage torque rise since the start of the test is displayed on the summary page and on printed reports. Percent Torque rise can be calculated as Torque Reserve or Torque Backup. Torque Reserve is calculated from the torque at the Rated PTO Speed to maximum torque.
Hand-held Engine Testing Using the Instrumentation Screens After the dynamometer has been found the Current instrumentation screen will display. There are two instrumentation screens, Current and Summary, are available and you can toggle between them by pressing F1 (SUMMARY/CURRENT). The Current screen provides a real time display of the power output, RPM and Torque that the dynamometer is measuring.
Chapter Four Hand-held Engine Testing Selecting the Load Control Mode Pressing F3 (MODE) from either instrumentation screen will allow you to select the dynamometer’s load control mode (Constant Speed, Constant Power, Direct or Auto). Press F3 (MODE) to step through until the correct mode is displayed in the pop-up window.
Hand-held Engine Testing Chapter Four Pre-Test Setup Before running a full engine test we recommend running a brief test to ensure that everything has been set up correctly and that the engine is capable of achieving the quoted high idle speed. The following assumes that you have followed the instructions in Chapters Two and Three up to and including “Starting the Dynamometer”...
Chapter Four The Automatic Test For the majority of general engine tests we recommend that you make use the of the Sigma Dynamometer’s Automatic Test mode. This automatic test sequence takes control of the dynamometer and runs tests to measure the engine’s maximum power, peak torque and power at nominal speed.
Hand-held Engine Testing Manual Testing Manual testing using the manual control modes provides direct control over the braking force that the dynamometer applies to the engine. It can be useful if you want to see how an engine performs at a specific load or range of loads, or when you want to measure the engine’s performance at a particular RPM.
Chapter Four Memory Mode The current load value can be stored in a memory at any time during a Constant Speed, Constant Power or Direct mode test. The stored value can then be recalled as load step changes from Memory mode. This can be useful if you need to check the engine’s governor response or check for clutch slippage.
Chapter Five Maintenance & Troubleshooting This chapter provides information about the routine maintenance of the dynamometer. It also contains diagnostic information that may be useful if you have problems operating the dynamometer.
Serious injury could result from contact with high voltage and extensive equipment damage due to short-circuiting of the cooling air. Avtron Dynamometer maintenance Weekly (or before each use) 1. Inspect the dynamometer looking for signs of damage and any obstructions to the airflow around the fan.
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1. Inspect the gearbox input shaft for cracks using a Penetrant Dye crack detector, follow the Penetrants manufacturer’s instructions to do this. Yearly 1. Ensure torque arm bolts are tight. 2. Contact Avtron technical support and arrange to have the dynamometer serviced and calibrated. 5 - 3...
Chapter Five Chapter Five Trailer Maintenance For the full list of trailer maintenance procedures please refer to the Knott trailer manual. Daily checks prior to use Trailer component Procedure Coupling head Ensure positive locking onto ball and wear indicator acceptable. Lighting Secure plug and check lights are operational.
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Maintenance and Troubleshooting Maintenance & Troubleshooting MOT Style Annual Checks Test Method Go/no-go Check drawtube for play Grasp and feel Max 1-2mm play at the play vertically and head horizontally Check damper operation Force inwards and allow Requires force to to extend compress and extend smoothly...
Chapter Five Dynamometer Status Indicators The POWER and START Indicators are a standard fitting on all dynamometer control panels. The operation of these indicators, along with the display on the Dynamometer Hand-held Terminal (hand-held), provides important diagnostic information if a fault should occur. Main Power Input Stop/Reset Button SIGMA Hand-held...
Maintenance and Troubleshooting Warning and Error Messages The Dynamometer has two indicator lamps as standard to indicate POWER ON and Running. The operation of these indicators, along with the display on the Dynamometer Hand-held Terminal (Hand-held), provides important diagnostic information if a fault should occur. Further error indicators are located on the I/O PCB, located behind the control panel.
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Chapter Five Message Reason Possible Causes • Gearbox switches Both proximity detector Faulty proximity detector or wiring. faulty on the signals are present. Check the proximity detectors dynamometer located on the gearbox. Phase load fault on Load not balanced between •...
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Maintenance and Troubleshooting Message Reason Possible Causes Close the Guard The guard is open • Guard is open if fitted on the Control The dynamometer is not • Start button has not been pressed Panel running. or was pressed before the Press START dynamometer had performed on the Control...
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Chapter Six Appendices This chapter displays supporting documents and information related to Avtron Dynamometers including certificates of conformities and general arrangement drawings.
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Chapter Six General Arrangement Drawing - Trailer Mounted 515 and 680 VIN Plate Position 1796 1751 1796 Gearbox PTO Drive Gearbox PTO Drive 2275 3860 1828 VIN Number Position Indented 8mm High Characters 1600 25 - Tracking 19/03/2024 FIRST ISSUE DESCRIPTION DATE REVISION HISTORY...
Chapter Six Declaration of conformity - CE EU Declaration of Conformity Product: Sigma Dynamometer Name of Manufacturer N J Froment & Company Limited, Easton-on-the-Hill, STAMFORD, PE9 3NP, United Kingdom Telephone +44 (0) 1780 920 100 e-mail support@avtronpower.com Website www.fromentdynamometers.com Country of Origin United Kingdom Object of Declaration: Sigma 515 (Trailer Mounted)
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Appendices Declaration of conformity - UKCA UK Declaration of Conformity Product: Sigma Dynamometer Name of Manufacturer N J Froment & Company Limited, Easton-on-the-Hill, STAMFORD, PE9 3NP, United Kingdom Telephone +44 (0) 1780 920 100 e-mail support@avtronpower.com Website www.fromentdynamometers.com Country of Origin United Kingdom Object of Declaration: Sigma 515 (Trailer Mounted)
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