The method of using a digital multimeter to determine wire and cable break points
In addition to measuring basic parameters such as voltage, current, resistance, capacitance, and transistors, digital multimeters can also be flexibly used to further expand their functions and achieve the goal of one meter for multiple purposes. Here is a method for using a digital multimeter to determine cable>wire and cable break points.
When there is a broken wire fault inside a cable or cable, the exact location of the broken wire is difficult to determine due to the wrapping of the external insulation skin. Using a digital multimeter can easily solve this problem. Specific method: Connect one end of the broken wire (cable) to the live wire of 220V mains power, and suspend the other end in the air. Pull the digital multimeter to the AC2V position, starting from the live wire connection end of the wire (cable), hold the tip of the black probe with one hand, and slowly move the red probe along the insulation of the wire with the other hand. At this time, the voltage value displayed on the display screen is about 0.445V (measured by DT890D type meter). When the red probe moves to a certain position, the voltage displayed on the display screen suddenly drops to a few tens of volts (about one tenth of the original voltage), and about 15cm forward (from the end of the live wire connection) from that position is where the wire (cable) breakpoint is located.
When using this method to check the shielding wire, if only the core wire is broken and the shielding layer is not broken, then this method is powerless.
Overview of Digital Multimeters
A digital multimeter is a small digital multimeter with a three and a half digit LCD display. It can measure AC and DC voltage, as well as AC and DC current, resistance, capacitance, transistor beta value, diode conduction voltage, and circuit short circuiting. The measurement function and range are changed by a rotating band switch, with a total of 30 levels.
