A new way to determine the breakpoint of a harness

In addition to measuring the basic parameters such as voltage, current, resistance, capacitance, and transistor, the digital multimeter can also be used through modification to further expand its function and reach the purpose of multi-purpose. A method for judging breakpoints of wire harnesses (wire and cable) using a digital multimeter is given.

When a wire breakage occurs inside the wire harness, the exact position of the wire break is not easily determined due to the wrapping of the external insulation sheath. Using a digital multimeter can easily solve this problem. specific method:

(1) Connect one end of the wire harness (wire and cable) with a breakpoint to the live line of 220V commercial power, and the other end is left unconnected.

(2) Pull the digital multimeter to AC2V, and start from the hot wire terminal of the wire harness (wire and cable). Hold the black stylus tip with one hand and slowly move the red lead along the insulation of the wire. The voltage value displayed on the display is approximately 0.445V (measured on the DT890D meter).

(3) Move the red pen. When the red pen moves to a certain place, the voltage displayed on the screen suddenly drops to a few tenths of a volt (approximately one tenth of the original voltage).

(4) About 15cm from this position forward (FireWire access point) is where the wire harness (wire and cable) breaks.

In addition, the expert cautioned that when using this method to inspect the shielded wire, if only the core wire is broken and the shielding layer is not broken, this method is powerless.