EDDY CURRENT DYNAMOMETER OF DW SERIES

Transcription

1 EDDY CURRENT DYNAMOMETER OF DW SERIES I

2 Eddy Current Dynamometer of DW Series I. Main usages and application range...1 II. Working and environment condition...1 III. Major technical parameters...1 IV. Design structure and principle...4 V. Conveyance and storage...5 VI. Installing and debugging...5 ⅰ. Foundation bed...5 ⅱ. Eddy Current Dynamometer installing...6 ⅲ. Dynamic machine installing...6 ⅳ. Connection...6 ⅴ. Cooling water system...8 ⅳ. Dynamometer wiring...9 VII. Dynamometer Calibration...10 VIII. Manipulation...11 IX. Maintaining and servicing...11 ⅰ. Maintaining instruction:...11 ⅱ.Servicing instruction...12 ⅲ.Common faults...12 ⅵ.Descaling...13 X. Whole set...13 XI. The dimension of the coupling of the dynamometer...13 XII. DW series(cylinder-patterned) inductive eddy current dynamometer...14 ⅰ. Main usages and applied range...14 ⅱ. Operating and environment condition...14 ⅲ. Main technical parameters...14 ⅳ.Design structure and principle...15 ⅴ.Installing and debugging...16 ⅵ.Calibration...17 ⅶ.Manipulation...18 ⅷ.Dimension of coupling of cylinder-patterned Eddy Current Dynamometer of DW series...18 II

3 I. Main usages and application range Currently, especially in medium-sized and subminiature dynamometer check, Eddy Current Dynamometer is the advanced loading dynamometer in China and compared with others, it is proved for its performance,price, reliability, maintainability and so on. The Eddy Current Dynamometer of DW series is designed to meet the output characteristic of medium-sized and pint-sized internal-combustion engine with the advantages of simple structure, slow moment of inertia, high limiting speed, wide dynamometer-range, least pendular resistance, and maneuverability,repetition,, which makes it handy for dynamometry of gearbox, medium-sized and pint-sized gas engine and its components in various conditions. Generally, the main accuracy classes are as follows: 1. Torque testing minimum: +_0.4% FS 2. Sensibility testing minimum: <= 0.1 FS 3. Speed testing minimum: +_ r / min Torque testing minimum can be up to +_ 0.2% FS, if clients request. And many derived series of Eddy Current Dynamometer is offered. Eddy Current Dynamometer consists of braking system and various measuring and controlling meters (including controller of loading, speed, torque and so on ).Our company s products are unique in ourselves' style, and easy to build new testing systems, when you need to. Undoubtedly, it is the best choice when you either purchase whole set or upgrade your inhered system. Advantages of Performance about Eddy Current Dynamometer of DW series: 1. Structure simple, handy to operate and maintain; 2. Strong braking torque, excellent performance of precision, and stability; 3. Slow moment of inertia, speedy dynamic reaction, strongly slow speed torque; 4. Be designed relevantly with observe and control system, automation is available. II. Working and environment condition 1. Field current power source of dynamometer: DC 0~60V, DC 0~80V, 0~100V, 0~180V 2. Field current of dynamometer: DC 0~3A, DC 0~5A, 0~10A 3. Cooling water:freshwater 4. Cooling hydraulic pressure: 0.02~0.1 Mpa 5. Rate of cooling flow: chart 9 6. Operation temperature: 0~40 C 7. Relative humidity: 20~90% RH III. Major technical parameters 1. The main technical parameters of DW/DWD series: table 1,table 2; Page 1 of 19

4 2. Maximum Excitation Voltage: DW 6, DC 60V; DW 10~40,DC 80V; DW 63~250,DC 100V; DW 300~400, DC 180V. Maximum Field Current: DW 6~40 3A, DW 63~250 5A, DW 300~400 10A. 3. Cooling hydraulic pressure: 0.02~0.1 Mpa Rate of water flow: chart 9 (it is determined by the absorption power and the difference of temperature between the water inlet and outlet. ) 4. Water output temperature of dynamometer: 55 C. 5. Rotation direction: clockwise or counter-clockwise, continuous work. 6. Torque testing minimum: ± 0.4% FS. 7. Speed testing minimum: ± r / min. Notice: DWD means Eddy Current Dynamometer of slow speed and strong torque series. TYPE Rated KW table 1: Rated Torque N.m main technical parameters of DW series Limiting Rated Torque Scope Speed r / min r / min Moment-of Inertia Kg.m DW ~ DW ~ DW ~ DW ~ DW ~ DW ~ DW ~ DW ~ DW ~ DW ~ DW ~ TYPE table 2: Rated absorbing power kw main technical parameters of DWD series Limiting Rated Torque SPEED N.m r / min Rated Torque Scope r / min DW ~1600 DW ~1600 DW ~1600 DW ~1600 DW ~1600 DW ~ Characteristic curves of dynamometer: chart1, chart2, chart3. Page 2 of 19

5 Chart1 and chart2 illuminates power-absorbing curves and torque-absorbing curves of eddy current dynamometer of DW series; chart3 illuminates torque- absorbing curves of eddy current dynamometer of DWD series. Please pay your attention on it, that the test is available if the characteristic curves of the tested dynamic machinery is within the area of DW/DWD. Chart 1 The characteristic curves of eddy current dynamometer of DW series Chart 2 Torque-absorbing curves of eddy current dynamometer of DW series ` Page 3 of 19

6 IV. Design structure and principle Eddy Current Dynamometer is consisted of rotating components ( induction tray ),pendular components ( armature and excitation parts ), force measuring components and calibrating components. (Chart 5) According to chart 5, the generation of flux in circuit by rotor and coaxal excitation coil when the DC electrified, through the closed circuit, which consists of armature, vortex ring, rotor and air-clearance. Because of the outer annulus surface of the rotor being alternate and uniform, and the magnetic field existing in the closed circuit, the vortex is excitated, when the rotor has been rotating. Then, the energy is transformed into torque because of the coupling action, which is detected by force sensor installed in armature. The export power of dynamic machinery is transformed into equivalence radiation by the armature and vortex ring, and the heat is taken away by the circulation cooling water. The intensity of braking torque is according to the field current, because the characteristic curve of torque of eddy-current arrester (M) is linear with that of SPEED of excitation coil. ( chart 4 ) The torque of armature equip is equal to that of dynamic machinery, and the sensor detect the force ( F ) which is transferred by the force-arm (whose length is L ) of armature. Then, M = F * L The formulation above means the force ( F ) pressed on the sensor is in direct proportion to the torque of export of dynamic machinery, and, the voltage output of the sensor is linear with the force ( F ), so that, we can get the torque output of dynamic machinery by measure the value of voltage signal. The pulse signal of electromagnetic tachogenerator can be used as the speed of dynamic machinery (n). Then power output of dynamic machinery is: P = *10e-4*M*n ( unit: M, N.m; n, r/min; P, kw) M 0 N chart 4 The sketch map of characteristic curves Page 4 of 19

7 Chart 5 The simple structure of Current Vortex Dynamometer 1.induction tray 2. main bearing 3.coupling unit 4.excitation coil 5.cooler 6.air-clearance 7.water outlet 13. external ring 14. base 8.grease cup 9. tachometer gear 10.bearing pedestal 11.water inlet 12.bearing ring V. Conveyance and storage 1. The products should be kept away from drench, inversion and impact. 2. Products conveyance without packaging is prohibited; the axial plane of the main bearing of the Eddy Current Dynamometer has to be vertical to advancing direction. 3. Limiting speed: 30+5 mph (third class), railway and ship is permitted. 4. There are pairs slinging holes in the base of the product; please make sure the pressure-pull sensor is safe, when slinging the product to install. 5. The storeroom has to be dry, ventilative and no corrosive gas. 6. Temperature range: -30 C~ +50 C (no water in the cooling system). VI. Installing and debugging ⅰ. Foundation bed The foundation bed of test-bed is used to install the eddy current dynamometer and engine. The design of the platform influences extremely the quality of the products. Please pay your attention to the follows: ( 1 ) The test-bed has to be closed to the water source, at least 1.5m distance from the wall to make sure there is adequate space for calibration arm. The whole room should be ventilative and bright. ( 2 ) To make sure the mass of the foundation bed is enough so that the oscillation of test-bed is minimal.( experientially, we strongly recommend that the value arrange is 40Kg/kW ~ Page 5 of 19

8 120Kg/kW; the more cylinders of engine the less mass of the foundation bed need.) The value of the concrete label number has to be larger than 90 and the proportion in bulk is 1 concrete, 2.5 sand, 4 gravel. The location of ground bolt in the foundation bed is according to the location of installing holes of the base of the Dynamometer. ( 3 ) Adopting effective vibration absorption measures to reduce the oscillation energy of the tested-bed losing. It is a simple way that filling up sand under the concrete foundation bed, grooving shock-proofs troughs, which are 20cm in width and 80cm in depth, filled up with slag and covered with asphaltum, around the foundation. Setting rubber absorber is another good way. ( 4 ) Underground equipments should be embedded before concrete moulding and if the vent-pipe of the dynamic machinery is designed to embed, it has to at least 0.5m distance from others. ⅱ. Eddy Current Dynamometer installing The Eddy Current Dynamometer has to be calibrated by gradienter with the accuracy class of to insure its sensibility and correctness. Then, reinforce the ground bolt, and get rid of the angle steel, which connect the inductorium with foundation. Generally, adopt the whole cast iron as the foundation of the test-bed. Chart 7, chart 8 and table 3 are the common installing steps and components measures. ⅲ. Dynamic machine installing The installing has to follow the instructions. To the ground bed that the type of the dynamic machine replacing frequently, you d better install it in a accessory bracket, which can move freely in the three mutually perpendicular lines (We could provide this product.), to handy for installing and adjusting. When you install the gasoline throttle actuator, make sure the travel of the timing handle within that of the gasoline throttle actuator. ⅳ. Connection Connecting the dynamic machine with the dynamometer rigidly is forbidden. You could choose the proper coupling according to your favor, but 4 important points have to be noticed. (1) The dynamometer can only bear radial load and axle load slightly. (2) The mass of the coupling, which collocated by yourselves, can not be more than twice of the accessory coupling which we provide. In other words, the mass of adjunction, which is connected rigidly with the original coupling, has not to be more weight than the original-packet one. (3) The accuracy class of moving-balance of the coupling ( including the apparatus that is tested) has to be more than G6.3. Security shield is indispensable. (4) Adjusting the coupling carefully to assure the error of centralization class is up to 0.1mm. (Chart 6) Whatever the connecting ways you choose, the accessory torque and axial force of the Page 6 of 19

9 dynamometer must be minimum. To avoid the accident, we strongly recommend that an accessory bracket is needed on the side of being close to the dynamometer. In the delivery testing, the power losing is not considered, when the dynamometer is as load. In other words, connecting the dynamometer with the pint-sized dynamic machinery in belt-flexible-driving or elastic padding coupling, when require of the precision of the testing is not strict, is available. Chart 6 The chart of the dynamometer installing 1. concrete foundation(part of the foundation bed) 2. installing plate 3. dynamometer 4. bracket of the dynamic machinery 5. dynamic machinery 6. ground bol Chart 7 Page 7 of 19

10 Chart 8 the chart of components measures Table 3 components dimension TYPE A B C D E F G H I J K L M DW / 4 DW DW DW DW / 4 DW / 2 DW (Notice: the measure of the DWD series is as same as the DW series.) ⅴ. Cooling water system 1 / / / / / / DW / DW DW / The cooling water system is a very important security system for the Current Vortex Dynamometer. When install the system, it is absolutely necessary to connect specified water pipes with the import and export of the dynamometer, check whether the system is aleak or not, and make sure the rate of flow is up to snuff and the cooling water alarm system works. The Eddy Current Dynamometer adopts electrical-contact manometer to monitor the hydraulic pressure. Adjust the meter of manometer before using, and ensure it can signal the excitation circuit of the dynamometer to disconnect and the dynamometer can not load, when the hydraulic pressure is lower than 0.02Mpa. The source of the cooling water can be tap water or circulating water. When you adopt circulating water, the temperature of water of import has not to be higher than 25 C. To pspeedent the generation of scale, the cooling water has not to contain with sand, salt, alkali and other corrosive matters; especially to the region where the water is calcified seriously, specified measures have to be implemented, otherwise the pipes will be blocked rapidly. We suggest mix in G1 in the cooling water and install filter to protect your system. Page 8 of 19

11 (r/min) 3 2 P(kW) Δt( ) Notice: The rate of cooling water accord to the difference in temperature, between the import and export of the dynamometer, and the absorbing power ( P ). The water rate in various working condition is on the assumption that the temperature of the water of the export is 55 C, so the rate of water has to be faster in actual to lower the temperature. Chart 9 water rate of the Current Vortex Dynamometer ( DW/DWD ) ⅳ. Dynamometer wiring Connect the control line of the excitation coil, pull-pressure sensor and tachogenerator according to the wiring map of the Engine Auto-Monitor System ET2000. ( 1 ) The points of the dynamometer junction box as follows: ( DW/DWD6 to DW/DWD 25 ) point 1 \ point 4: switch of hydraulic pressure Page 9 of 19

12 point 2(+) \ point 3(-): power supply of excitation plug receptacle of torque \ speed : point 1: +V import of bridge voltage point 2: + import of positive torque signal point 3: -V import of bridge voltage point 4: - import of negative torque signal point 5: GND point 6: ZS+ output of speed signal point 7: ZS- output of speed signal ( 2 ) The points of the dynamometer junction box as follows: ( DW/DWD40 to DW/DWD 400 and from left to right ) V+ Out+ V- Out- GND ZS+ ZS- K1 K2 DL+ DL- POWER SUPPLY + OUTPU T + POWER SUPPLY - OUTPUT - GROUND SPEED + SPEED - HYDRAULIC SWITCH HYDRAULIC SWITCH NULL EXCITATION POWER SUPPLY + The point 1 to point 7 are according to the points of the secondary meter CX16Z7. The point 8 / 9 / 11 / 12 are connected with the point 1 / 4 / 2 / 3of the secondary meter P20. VII. Dynamometer Calibration EXCITATION POWER SUPPLY - Strict calibration should be taken, before using it, to ensure the precision of testing. Twice in one year is average, however, calibration has to be carried out immediately, when the state of dynamometer is abnormal. Calibration steps as follows: 1. Insert the special pins in both sides of the Dynamometer case, install the calibration arm, and screw down the nuts. Although the Dynamometer could rotate to absorb power and be demarcated with weights both in clockwise and counter-clockwise way, it should be demarcate on the side of the tested machine rotating. 2. Set the secondary meter value to zero before demarcating. 3. Do not stop increasing weights in the salver until the value of the secondary meter to maximum. (The maximum value can be set as you need.) Manipulate the secondary meter to assure the displayed value is as same as the full travel value. Take away all the weights, and the value of the meter should be back to zero (or the error could be endured). 4. Do not stop increasing weights until the value is maximal and decrease to zero gradually until the difference between the import value and the displayed value is up to the precision grade. 5. Take down the calibration arm and set the value of secondary meter to zero again. All the equipped weights are 4 th class weights in national standard and the weights value are set as Newton value. Page 10 of 19

13 VIII. Manipulation The follow steps should be taken before startup the tested engine: 1. Make sure the testing and controlling meters, which is designed relevantly with the Dynamometer such as the Engine Auto-Monitor System ET2000, are in constant DC or torque mode, the initialization value is zero, and the tested engine is started with no load. 2. When open the penstock, the cooling water will through the penstock and pressure-control implement into the cavity of the Dynamometer. If the hydraulic pressure is lower than 0.02Mpa, the Dynamometer will not work to avoid accident. 3. According to the testing range of the tested engine, the Dynamometer will change load automatically to follow the change of the field current by changing the control mode and digital value mode, so that the absorbing power can be tested. 4. Check the temperature of water outlet carefully, and modify the flow rate to ensure the temperature is lower than 55 C. 5. After testing, decrease the field current to zero; stop tested engine after unloading; stop water circulation system and close penstock. Notice: starting the Eddy Current Dynamometer has to on the base of cooling water system working, otherwise the machine will be burned. IX. Maintaining and servicing ⅰ. Maintaining instruction: Period Objects Point Method Reference Each day Every three months Main body Of the Dynamometer Insulated resistance Main body Of the Dynamometer hydraulic pressure controller Abnormal oscillation and noise Super-heat Water leakage hydraulic pressure Excitation loop and insulated resistance Oscillation and error of centralization switch Listening carefully Thermometer Manometer Megohm meter 1. vibrograph 2. micrometer Test pressure value and whether import exist at the connection point of switch Axle: 65 C Output water: 55 C 0.02MPa hydraulic pressure 0.1MPa More than 10 megohm Refer the test records Refer the set value cable Appearance and connection Check breakage Update cable Page 11 of 19

14 Every six months Clean dust Cooling water Flow rate Flowmeter Main body Of Demarcation Check with the demarcating the method Dynamometer Max: 30L / kw.h ⅱ.Servicing instruction Period Objects Request Detail Every 1.bearing pedestal 2.bearing No abrasion and dent 5 degrees rotation in same direction each time Three months Every Six months Main bearing No superheat abrasion and Add high-temperature lubricant in every three months cracking or while the accumulative working time is more than 500 hours Cooling water pipe No block Clean the pipe with weak acid or special scale-borer. Fixed implements No loosing Check and replace if necessary Adjusting arm No deformation weight No corrosion Avoid abrasion and impact, and check them periodically. ⅲ.Common faults Faults types No torque absorbing Weak Torque Absorbing Superheat for the main body Abnormal noise Reason Method Obstacle avoidance No power supply Check the switch of power supply Switch on again Open circuit Checking by millimeter Replace new one Deficiency of voltage Check according to the fault-monitor lights Bad connection Checking by millimeter Fix all the components 1.Re-demarcation by weights 1. Refer to the content of 1. No zero set for torque meter 2.checking the resistance of demarcation 2. Short circuit of dynamometer coil excitation coil by multimeter 2. Replace new one 1. rate of cooling water is lower 1. checking hydraulic pressure 1. Accelerate the flow 2. pipe blocked 2. checking the absorbing state 2. Clean the water pipe 3. over loading of absorbing-power 3. testing the water temperature 3. Choose another 4. temperature of cooling water is too of the pipe input dynamometer high 1. bad coaxiality 1. Re-coaxiation 1. Re-coaxiation 2. bolts and nuts loosing 2. Testing the noise of bearing 2. Fix the bolts and nuts 3. bearing abrased 3. fixing the bolts and nuts 3. Replace new one Page 12 of 19

15 ⅵ.Descaling To protect your system, descaling and cleaning should be periodically and desalting liquid choosing should accord to the region you are in China. Generally, the main element of scale is calcium ion in inland, however, that is magnesium and natrium ion in coastland. Method: replace the upside cooling water pipe of the vortex braking implement with soft pipe and insert special desalting liquid by pump to clean the circulated system. After cleaning, insert neutralizing agent to deal with the rudimental desalting liquid, because of its causticity. Clean the system once a year in common, and anytime when you need. Judgement standard: 1. The flow rate of water outlet is lower than before. 2. The feeling temperature of output higher a little than before. The states usually both exist. You d better choose the pump, which the max rate is 80L / min and max raising height is 10m. X. Whole set Instruction 1 Quality certification 1 Products list 1 Static adjusting system 1 (including 1 connecting annul and 2 nuts) Notice: the static adjusting system will not be provided until you apply for it when you order the goods. XI. The dimension of the coupling of the dynamometer Chart 10 the dimension map (DW/DWD) Table 4 The data of the dynamometer dimension (DW / DWD) TYPE A B C D E F DW6 6-φ6.5 46h DW10 6-φ7 42h DW16 6-φ7 42h Page 13 of 19

16 DW25 6-φ7 52h DW40 6-φ8.5 75h DW63 6-φ8.5 75h DW100 8-φ h DW160 8-φ11 90h DW250 8-φ11 90h DW400 8-φ XII. DW series(cylinder-patterned) inductive eddy current dynamometer ⅰ. Main usages and applied range To satisfy the need for performance testing of the pint-sized gas engine, such as the motorcycle engine, universal engine and so on, our company has developed the seal, cylinder-patterned, inductive eddy current dynamometer. ⅱ. Operating and environment condition Excitation electrical source of dynamometer: DC 0~90V, DC 0~120V Field current of dynamometer: DC 0~3A, DC 0~4A Cooling water: fresh water Cooling hydraulic pressure: 0.04~0.1 Mpa Rate of cooling flow: chart 9 Working temperature: 0~40 C Relative humidity: 20~90% RH ⅲ. Main technical parameters 1. The main technical parameters of DW series: table 1,table ( 1 ) Maximum Excitation Voltage: DW 6~DW 16, DC 90V; DW 25~DW40,DC 120V; ( 2 ) Maximum Field Current: DW 6~DW 16 3A; DW 25~40 10A. 3. ( 1 ) Cooling hydraulic pressure: 0.04~0.1 Mpa (the water temperature is held the line by the pressure) ( 2 ) Rate of water flow: chart 9 (it is determined by the absorbing power and the difference of temperature between the input and output ) 4. Output temperature of dynamometer: 55 C 5. Rotating direction: clockwise or counter-clockwise, continuous work. 6. Torque testing minimum: ± 0.4% FS. Page 14 of 19

17 7. Speed testing minimum: ± r / min. 8. Characteristic curves of dynamometer: chart1, chart2. Table 1: the main technical parameters of DW series TYPE Rated absorbing power kw Rated Torque N.m Limiting SPEED R / min Rated Torque Scope DW ~3800 DW ~3800 DW ~3800 DW ~3200 DW ~3300 DW ~3500 ⅳ.Design structure and principle The column type Eddy Current Dynamometer consists of rotating components ( induction cylinder ),pendular components ( armature and excitation parts ), force measuring components and calibrating components. (Chart 5) According to chart 5, when the DC electrified, flux is generated around the excitation coil in the closed circuit. The magnetic field density is changing in periodically, while the induction column is rotated by the dynamic machinery, so that the vortex is generated at the appearance of the vortex ring. And then, the magnetic field, generated by the vortex, is interacting with air-clearance field to generate the braking torque, detected by sensor and transformed into electrical signal by force sensor, so the torque is detected. In order to test the speed, signal has to be transformed into electrical signal by non-contacted, electromagnetic sensor. Chart 1 The characteristic curves of power of cylinder-patterned Current Vortex Page 15 of 19

18 Chart 2 Dynamometer of DW series The characteristic curves of torque of cylinder-patterned Current Vortex Dynamometer of DW series Chart 3 The structure of cylinder-patterned Current Vortex Dynamometer of DW series 1.base 2. input/output pipe 3. bearing pedestal 4. tachometer gear 5. main bearing 6. induction column 7. excitation coil 8. external annulus 9. magnetizer 10. end supporting 11. grease cup 12. coupling ⅴ.Installing and debugging 1. To make sure the dynamometer connect with the motor firmly, both of them have to be installed in the same soleplate. The concrete foundation should firm and solid enough to bear both the static and dynamic loading. Use gradienter to adjust the soleplate before installing. When the dynamometer working, its main bearing can not endure axial force, so it should be connected with tested engine elasticly and the dynamometer has to be coaxial with tested engine strictly. After installing, use ground bolts to fix the dynamometer and remove the angle iron, which connect the base with the induction tray. Page 16 of 19

19 Chart 4 The chart of dynamometers dimension Table 2 The data of dynamometer dimension TYPE A B C D E F G H I J K L M DW G 1 / 2 G 1 / DW G 1 / 2 G 1 / DW G 1 / 2 G 1 / DW G 1 / 2 G 1 / DW G 1 / 2 G 1 / DW G 3 / 4 G 3 / The cooling water system is a very important security system for the Eddy Current Dynamometer. When install the system, it is absolutely necessary to connect specified water pipes with the import and export of the dynamometer, check whether the system is leak or not, make sure the rate of flow is up to snuff and the cooling water alarm system works. Engage a manometer (0~0.1Mpa) at the water inlet of dynamometer. The constantly close points are connected with the point 1 and point 4 of receptacle of excitation power supply and ensure the points of manometer turn to be constantly open, when the value of manometer up to 0.02Mpa. To prepare the generation of furring, the cooling water has not to contain with sand, salt, alkali and other corrosive matters; especially to the region of the water calcified seriously, specified measures have to be implemented, otherwise the pipes will be blocked rapidly. We suggest mix in G1 in the cooling water and install filter in the import to protect your system. 3. Install pull-pressure sensor and speed-testing sensor, according to the map of Engine Auto-Monitor System ET2000. ⅵ.Calibration Strict adjusting should be taken, before using, to ensure the precision of testing. Twice in one year is average, however, adjusting has to be carried out immediately, when the state is abnormal. Calibration steps as follows: 1. Insert the special dowels in both sides of the Dynamometer shell, install the adjusting arm, and screw down the nuts. Although the Dynamometer could speedolve to absorb power and be demarcated with weights both in clockwise and counter-clockwise way, it should be demarcate in the side of the tested machine speedolving. 2. Set the secondary meter value to zero before demarcating. 3. Do not stop increasing weights in the salver until the value of the secondary meter to maximum (the maximum value can be set as you need). Manipulate the secondary meter to assure the display value is as same as the maximum-scope value of import. Take away all the weights, and the value of the meter should be back to zero (or the error could be endured). 4. Do not stop increasing weights to the maximum and decreasing to zero gradually until the difference between the import value and the display value measure up the precision grade. 5. Take down the adjusting arm and set the value of secondary meter to zero again. All the equipped weights are 4 th class weights in national standard and the weights value are Page 17 of 19

20 set as Newton value. ⅶ.Manipulation The follow steps should be taken before startup the tested engine: 1. Make sure the testing and controlling meters, which are designed relevantly with the Dynamometer such as the Engine Auto-Monitor System ET2000, are in constant DC or torque mode, the initialization value is zero, and the tested engine is started with no load. 2. When open the penstock, the cooling water will through the penstock and pressure-control implement into the chamber of the Dynamometer. If the hydraulic pressure is lower than 0.02Mpa, the Dynamometer will not work to avoid accident According to the testing scope of the tested engine, the Dynamometer will auto-change load to follow the change of the excitation current by changing the control mode and digital value demarcating mode, so the absorbing power can be tested. 4. Check the temperature of output water carefully, and modify the flow rate to ensure the temperature is lower than 55 C. 5. After testing, decrease the excitation current to zero; stop tested engine after unloading; stop water circulation system and close penstock. Notice: starting the Current Vortex Dynamometer has to on the base of cooling water system working, otherwise the machine will be burned. ⅷ.Dimension of coupling of cylinder-patterned Eddy Current Dynamometer of DW series chart 5 table 3 TYPE A B C D E F DW6 6-φ6.5 46h DW10 6-φ7 42h DW16 6-φ7 42h Page 18 of 19

21 DW25 6-φ7 52h DW40 6-φ8.5 75h DW63 6-φ8.5 75h DW100 8-φ h DW160 8-φ11 90h DW250 8-φ11 90h DW400 8-φ Page 19 of 19