2. Determination of dc resistance of winding: 1) Significance of dc resistance measurement: The dc resistance of the windings in cold state is one of the main parameters of three-phase asynchronous motors. By comparing the measured value of the resistance of the windings with the design value, it is possible to check whether the windings have broken wires and short-circuit between turns, whether the welding parts have virtual welding or open welding, whether the contact points have bad contact and other phenomena. 2) Dc resistance measurement method: Measuring the dc resistance of the motor should be done when the winding is cold. First, place the motor indoors for a period of time, and measure the temperature of the motor winding end or core with a thermometer. At this time, the measured temperature is the actual temperature of the winding in the cold state. If the temperature of the winding end or core cannot be measured, the temperature of the housing may be substituted
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