Clothes Washer, Wet Test, Temperature Measurement (3.e) Inlet Water Temperature Measurements A signal from each thermocouple attached to the inlet pipe (as shown on Figure 3.e-1 on page 26) to measure the inlet water temperature was collected simultaneously with the other measurements (from the laser optical tachometer, load cell or force transducer, and tri-axial accelerometer). The data acquisition device began collecting data before the clothes washer began operating. The total acquisition time was 3,120 seconds, using 64 Hz sample rate measurements. The clothes washer contained two lbs (dry weight) of test clothes, with high water level and a warm water temperature setting. Note that each measurement started at different time frame thus there were some minimal delays as shown in Figure 3.e-2 on page 26. The differences (also shown on Figure 3.e-2 on page 26) were very minimal and thus insufficient to impose any immediate problem toward the measurement. Since the inlet water was supplied by the campus-wide water supply, controlling the temperature of the inlet water was redundant and unnecessary. This is especially true for cold water supply. For the hot water supply since it is maintained at a constant temperature within an individual building. And the hot water’s temperature cools off over time whenever the water is not flowing in the water supply pipe. It gradually rises to approximately the maintained temperature whenever it is permitted to flow. Thus, variations in the hot inlet water temperature level at different time frames throughout the laundry cycle will be observed. Created by Phie Theng Lee Michigan Technological University 25 Clothes Washer, Wet Test, Temperature Measurement Thermocouple Figure 3.e-1, Thermocouple attached to the inlet water pipe. Regular wash cycle @ 64 Hz sample rate 120 Fast spin speed Medium spin speed Slow spin speed Temperature, degree Fahrenheit 115 110 105 100 95 90 85 0 500 1000 1500 Time, second 2000 2500 3000 Figure 3.e-2, Hot inlet water temperature measurement for Regular Wash Cycle. Created by Phie Theng Lee Michigan Technological University 26 Clothes Washer, Wet Test, Temperature Measurement (3.f) Drain Motor Temperature Measurement A signal from a thermocouple attached to the housing of the drain motor (as shown in Figure 3.f-1 on page 28) was collected simultaneously with the other measurements (i.e. laser tachometer, load cell and tri-axial accelerometer). The data acquisition device began collecting data before the clothes washer began operating. The total acquisition time was 3,120 seconds, using 64 Hz sample rate for the measurement. The clothes washer contained two lbs (dry weight) of test clothes, with high water level and a warm water temperature setting. Each measurement started at a different time frame that leads to apparently an insignificant amount of delay (as shown in Figure 3.f-2 on page 28). Also shown in Figure 3.f-2 on page 28, the first couple of peaks were at approximately 500 seconds or eight minutes into the wash cycle, inconsistent maximum temperature levels were due to the initial temperature of the drain motor. If the measurement was performed at the very beginning before a series of measurements compared to any other measurement in that series, the drain motor’s temperature will be lower (the cold start). This behavior will not persist once the drain motor got past the warm up period, as seen from Figure 3.f-2 on page 28, the drain motor reached a more consistent maximum temperature level after approximately 1,250 seconds or twenty minutes into the wash cycle. As the drain motor, its operating temperatures were within the range of 143° F to 150° F that occurs at the very end of the drain cycle that spread throughout the entire wash cycle. Created by Phie Theng Lee Michigan Technological University 27 Clothes Washer, Wet Test, Temperature Measurement Thermocouple Located at here Figure 3.f-1, Thermocouple was attached to the drain motor housing. Regular wash cycle @ 64 Hz sample rate Fast spin speed Medium spin speed Slow spin speed Temperature, degree Fahrenheit 160 150 140 130 120 110 100 0 500 1000 1500 2000 Time, second 2500 3000 3500 Figure 3.f-2, Drain motor temperature measurement for Regular wash cycle. Created by Phie Theng Lee Michigan Technological University 28 Clothes Washer, Wet Test, Temperature Measurement (3.g) Drive/Spin Motor Temperature Measurement Two different types of thermocouples were used to measure the clothes washer’s drive motor’s core temperature level. The thermocouples were attached at two different locations of the drive/spin motor’s coil. The measurement was conducted simultaneously with the other measurements (from laser tachometer, load cell and tri-axial accelerometer). The data acquisition device began collecting data before the clothes washer began operating. The total acquisition time was 3,120 seconds (entire wash cycle), using 64 Hz measurement sample rate. The clothes washer contained two lbs (dry weight) of test clothes, with high water level and a warm water temperature setting. As shown in Figure 3.g-1 on page 30, both of the thermocouples were attached to two different copper coils that were located at different spots of the stator. The main reason for placing two different types of thermocouples at two different spots of the stator is to distinguish any observable differences in temperature level by using two different thermocouples with different thicknesses. If both of the thermocouples were properly calibrated, and if both of the thermocouples were measuring the temperature level of the same object, then the temperature level obtained should be approximately the same, as shown in Figure 3.g-2 on page 30 and Figure 3.g-3 on page 31. The temperature level as measured during the clothes washer was cycle at Fast spin speed was relatively higher then the rest of the cycles as shown in Figure 3.g-2 on page 30 and Figure 3.g-3 on page 31. This was due to the drive motor requiring higher amount of energy in order to spin up to the higher spin speed. It was approximately the same for the Medium and Slow spin speed. The stator is the internal component of the clothes washer’s drive motor, the stator is fixed and does not rotate. The stator is the white plastic piece as shown in the middle of Figure 3.g-1 on page 30. Created by Phie Theng Lee Michigan Technological University 29 Clothes Washer, Wet Test, Temperature Measurement Thermocouples Figure 3.g-1, Thermocouples attached to the clothes washer’s copper coil. Regular wash cycle @ 64 Hz sample rate, Thermocouple # 1 Fast spin speed Medium spin speed Slow spin speed Temperature, degree Fahrenheit 180 160 140 120 100 80 0 500 1000 1500 2000 Time, second 2500 3000 3500 Figure 3.g-2, Drive/spin motor temperature measurement for Regular wash cycle with thermocouple # 1. Created by Phie Theng Lee Michigan Technological University 30 Clothes Washer, Wet Test, Temperature Measurement Regular wash cycle @ 64 Hz sample rate, Thermocouple # 2 Fast spin speed Medium spin speed Slow spin speed Temperature, degree Fahrenheit 180 160 140 120 100 80 0 500 1000 1500 2000 Time, second 2500 3000 3500 Figure 3.g-3, Drive/spin motor temperature measurement for Regular wash cycle with thermocouple # 2. Created by Phie Theng Lee Michigan Technological University 31