Resistance measurement can be applied in many places. In the electrical line maintenance, the resistance measurement method can also quickly find out the circuit failure. Generally, we use resistance measurement methods such as voltmeter-amperometry, resonance method, ohmmeter method, DC bridge method, digital ohmmeter method, etc., and the most commonly used method for measuring resistance in electrical circuit control failure is the method of measuring resistance. 

First, the resistance measurement method to determine the continuity of the line
We know that there are many reasons for line faults. Usually we use the exclusion method to check. Before we use the resistance measurement method to find the fault point, we first disconnect the two ends of the control circuit from the control power supply, and then put the multimeter in R ́10 or R ́100 file to measure. The segmentation measurement method is generally used to check whether the line is faulty. The long segmentation method is used to measure the on-off condition of a branch; the short segmentation method is used to measure the on-off condition of one or several components in the branch. Our normal resistance measurement should be 0Ω. If the measured resistance value is infinite, it indicates that the section is broken. At this time, we should consider repairing this circuit. 
 
2. Resistance measurement method to detect DC resistance values of other electronic components
The problem of faults in the line is usually also reflected in an electronic component. If one of the electronic components is damaged, the circuit will also malfunction. At this time we are going to test the resistance measurement method in the electric drive control circuit. Our commonly used components are capacitors, various relays, fuses, control buttons and so on. When testing, we refer to the parameters and time of use of the relevant devices for testing, and record the DC contactor coils used in the circuit and the DC resistance of various relay coils, so that we can judge when the electrical equipment is overhauled. 

Usually, we can quickly find the control circuit in the resistance measurement method. There is a problem with the circuit or the electronic components are damaged, so that we can follow up the repair in time to restore the control circuit. However, when we use the resistance measurement method, we need to pay attention to the fact that it can be used in any situation. We also need to use different detection methods according to different situations.