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The basic procedure for running the engine and taking data is as follows:
| 1. | You may wish to fill the white plastic water box with an ice/water mix to within one inch (2.5 cm) of the top. An ice bath is not required; however, maximum speed and power is only achieved with an ice bath, to get the cold plate of the engine to be as cold as possible. |
| 2. | Plug the supplied 9 V power brick into the 9 V connector to provide power to the on-board electronics. The front panel LED should light up, and the temperature display should show a temperature reading. |
| 3. | Connect a USB cable from the engine to your Windows PC. The green light on the top of the DAQ should light up, indicating successful communications with the PC. Start the Smart Engine Data Logger software. Among other things, this software monitors the temperature of the hot plate, to ensure that you do not allow the plate to get too hot. You should always run the Smart Engine Data Logger software whenever the heating resistors are powered up. |
| 4. | Verify that your variable voltage DC power supply is turned off and then connect the wires from the DC power supply to the red (positive) and black (negative) binding posts on the lower right portion of the front panel to provide power to the heating resistors. |
| 5. | Adjust your power supply so it is supplying 12 volts at about 3 amps, or about 35 watts. After the power has been turned on, it may take three to five minutes before the engine is hot enough to run, since Stirling engines do not start instantly or automatically. You can monitor the temperatures by inspecting the temperatures shown on the LCD display on the black electronics box at the right rear of the engine, or by watching the pair of temperatures displayed under the Quit button by the Smart Engine Data Logger software. When the engine has become hot enough (generally a 20 C temperature difference), gently spin the output shaft clockwise by hand to start the engine. If the engine is hot enough, it will start quickly, and build up speed. If the engine is not hot enough, no amount of spinning will make it start. Air leaks (sometimes caused by pinch clamps that are not tight enough) can also cause the engine to fail to start, even when hot. You should keep the engine running at all times while the engine is being heated: if the engine stops running, heat starts to build up on the hot plate, and the engine may over heat. If the hot plate on the engine gets too hot, either turn the 12 V power supply off, or lower the voltage and/or current. |
| 6. | While exact performance will differ with changing atmospheric conditions and the condition of your engine, the Smart Engine needs a temperature difference of approximately twenty degrees C to run when its working fluid is air, and ten degrees C if helium is used as the working fluid. Maximum performance is achieved with the hot side at the maximum allowable temperature of 370 K and the cold side at 273 K. Note that if you exceed the maximum hot temperature of 370 K, the engine may develop a leak, and may stop working entirely: monitor that temperature carefully while running the engine. |
| 7. | This engine spins clockwise when you are looking at it from the front. It is worth noting that you cannot harm the engine by spinning it backwards. In fact, if the engine is hot and is spun backwards, it may come to a complete stop, reverse itself, and run in the clockwise direction. |
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