I. Overview
The CW series eddy current dynamometer, also known as electromagnetic dynamometer, uses the principle of eddy current loss to absorb power. The dynamometer consists of a dynamometer, controller, and force measuring device, which can measure the output torque and speed of the tested machinery, thereby obtaining the output power. It can replace magnetic powder clutches, hydraulic dynamometers, DC generator sets, etc., and is used to measure the performance of various power machinery such as electric motors, gasoline engines, diesel engines, gearboxes, etc. It has become a necessary equipment for type testing. Compared with other dynamometer devices, the CW series dynamometer has higher reliability, practicality, and stability.

2、 Main features
1. Simple structure, stable operation, low price, and convenient use and maintenance;
2. Using water cooling, with low noise and minimal vibration;
3. Wide input speed range, suitable for type testing of various motors and power machinery such as variable frequency speed regulation;
4. The controller adopts a single-phase AC power supply, with low control power;
5. Torque measurement can be carried out using electronic scales, pressure sensors, or high-precision torque and speed measuring instruments, which are suitable for situations with different measurement accuracies.
6. The device can also be used as a brake, with a large braking torque

3、 Usage environment
1. The maximum ambient temperature shall not exceed 40 ℃
2. Altitude not exceeding 1000m
When the ambient temperature is 30 ℃, the relative humidity should not exceed 85%

4、 Cooling
1. Water quality
The cooling water is tap water, general industrial water, groundwater, or preliminarily filtered river water. The water should not contain solid particles or other impurities with a diameter of more than 1mm, with a pH value of 6-8 and a hardness of less than 200ppm, with a maximum value of 300ppm.
2. Water pressure
The inlet pressure is generally not less than 0.05Mpa and not more than 0.2Mpa. This product does not have strict requirements for water pressure. It is recommended that users add an inlet valve when installing and using this product to facilitate the adjustment of water volume.
3. Water volume
The cooling water volume is shown in the parameter table, and the inlet water volume is adjusted according to the different test powers.
4. Water temperature
The maximum inlet temperature should not exceed 30 ℃, and the outlet temperature should be around 50-60 ℃. The cooling water volume can be adjusted according to the outlet temperature during use.

5、 It can be controlled with a matching dynamometer or with an adjustable DC power supply. The electrical performance of the controller should match the technical parameters of the dynamometer.

6、 Key points for the correct use of CW series eddy current dynamometer
1. Select the dynamometer correctly according to the rated torque.
2. Before operation, the dynamometer must be inspected to verify whether the nameplate data meets the required specifications, whether the fasteners are loose, whether the wiring of each terminal block is correct, and whether the contact is good. If there are defects or defects, they should be eliminated or replaced. Use a 500 volt megohmmeter to check the insulation resistance of the excitation winding and the stator winding of the tachometer generator, which should not be less than 12M Ω.
When installing the product, extend the shaft horizontally, place the foot flat, and tighten the anchor bolts. Connect the input shaft to the tested machine or torque speed tester, and connect the output shaft to the force measuring rod.
4. Connect the connecting wires according to the terminal markings (as shown in the figure), and ground the ground wire on the grounding screw.
5. During installation, connect the inlet and outlet pipes according to the markings on the dynamometer. An inlet valve should be added in front of the inlet pipe to adjust the water flow. When unmarked, the inlet and outlet can be interchanged.
Before loading (adding excitation), cooling water must be introduced first, and after unloading (removing excitation) for five minutes, the cooling water can be disconnected.
7. Start the tested machinery and wait for it to operate normally. Connect the excitation output, adjust the excitation current, measure the output torque, and pay attention to subtracting the initial value.
8. During operation, pay attention to monitoring the outlet water temperature. If it exceeds 70 ℃, increase the cooling water volume.
7、 Maintenance and repair
1. The surroundings of the dynamometer should be kept clean, and the inlet and outlet should be kept unobstructed.
After the dynamometer is put into operation, lubricating grease (molybdenum disulfide composite calcium based grease) should be regularly added to the bearings.
After two years of operation, major repairs should be carried out to clean the bearings and replace the lubricating grease. If the bearings are found to be damaged, they should be replaced.

CW series eddy current dynamometer