測定電機各部分溫度的方法：

       一、溫度計法：

       此法用溫度計直接測定溫度，Z為簡便。但用溫度計僅能接觸到電機各部分的表面;所測得的僅為表面溫度。用溫度計無法測出電機內部的Z高溫度。

       二、電阻法：

       此法只能用以測定繞組的平均溫度，原理如下。

       在電機運轉以前，我們先測得繞組的冷態電阻r1，．即當繞組溫度等于冷卻介質溫度t1時的電阻。設電機運轉以后繞組的濕度升高至t2， 繞組的電阻便增加至r2。加溫度用攝氏來量度，則對銅線繞組有下列關系：r1/r2=（235+t1）/（235+t2） .由上式可知，如r1、r2和t1為已知，便可求解t2。t1-t2，便是該繞組對冷卻介質的溫升。對子鋁線繞組，將上式中常數235改為225。

       三、疊加法(雙橋帶電測溫法)：

       在不中斷交變的負載電流的情況下，在負載電流上疊加一微弱直流電流，以測量繞組直流電阻隨溫度而發生的變化從而確定交流繞組的溫升。電機各部分的溫升限度與所用絕橡材料的級別有關，與冷卻介質的溫度有關，也與測量溫度的方法有關。絕緣材料的壽命決定于它在遠行時的絕對溫度，而不決定于溫升。從冬季到夏季，從北方到南方，環境溫度的變化很大。當環境溫度較低時，電機的溫升限度可以提高，而當環境溫度較高時，電機的溫升限度必須降低。為了明確起見，在規定電機各部分的溫升限度時，必須同時規定冷卻介質的標準溫度。我國電工技術標準規定冷卻介質的標準溫度為4Q℃。依據此規定，電機各部分的溫升，應用不同的絕緣材料以及用不同測溫方法，有不同的溫升限度。     四、埋量檢溫計法：

       較大的電機，在裝配時，常在估計到可能有較高溫度的各點，埋置檢溫計。檢溫元件有熱電偶及電阻溫度計等。檢溫計的受熱端，可以埋在槽的深處，例如導體與橫底之間、上下層導體之間。檢溫計的引出端引至外面，接至測量儀表，借以讀出溫度。應用的檢溫計愈多，則所測得的溫度愈有可能接近于Z熱點的溫度。

Methods of measuring the temperature of each part of the motor:

       1. Thermometer method:

       This method uses a thermometer to directly measure the temperature, which is the simplest method. However, the thermometer can only touch the surface of each part of the motor; what is measured is only the surface temperature. The maximum temperature inside the motor cannot be measured with a thermometer.

       2. Resistance method:

       This method can only be used to determine the average temperature of the winding, and the principle is as follows.

       Before the motor runs, we first measure the cold resistance r1 of the winding. That is, the resistance when the winding temperature is equal to the cooling medium temperature t1. Assuming that the humidity of the winding increases to t2 after the motor is running, the resistance of the winding increases to r2. The temperature is measured in Celsius, and the following relationship exists for the copper wire winding: r1/r2=(235+t1)/(235+t2). From the above formula, we can see that if r1, r2 and t1 are known, it can be solved t2. t1-t2 is the temperature rise of the winding to the cooling medium. For the aluminum wire winding, change the constant 235 in the above formula to 225.

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       3. Superposition method (double bridge live temperature measurement method):

       Without interrupting the alternating load current, a weak direct current is superimposed on the load current to measure the change in the DC resistance of the winding with temperature to determine the temperature rise of the AC winding. The temperature rise limit of each part of the motor is related to the grade of the insulating rubber material used, the temperature of the cooling medium, and the method of measuring the temperature. The life of the insulating material is determined by its absolute temperature during long travel, not by the temperature rise. From winter to summer, from north to south, the environmental temperature varies greatly. When the ambient temperature is low, the temperature rise limit of the motor can be increased, and when the ambient temperature is high, the temperature rise limit of the motor must be lowered. For the sake of clarity, when specifying the temperature rise limit of each part of the motor, the standard temperature of the cooling medium must be specified at the same time. my country's electrical engineering standards stipulate that the standard temperature of the cooling medium is 4Q℃. According to this regulation, the temperature rise of each part of the motor, the application of different insulating materials and the use of different temperature measurement methods, have different temperature rise limits. 4. Buried quantity thermometer method:

       For larger motors, when assembling, thermometers are often embedded at points where it is estimated that there may be a higher temperature. The temperature detection components include thermocouples and resistance thermometers. The heated end of the thermometer can be buried in the depth of the groove, for example, between the conductor and the bottom, and between the upper and lower conductors. Lead the leading end of the thermometer to the outside and connect it to a measuring instrument to read the temperature. The more thermometers are used, the more likely the measured temperature will be close to the hottest temperature.