The core of a cable is an important component of the cable, and we transmit information through it. If the cable is broken, it can bring many troubles and dangers. So, how should we check if the cable is broken? Some people may say to get a multimeter, but if it's a big project, we can't also use a multimeter? So how should we search? Don't worry, let me introduce three methods.
1： Method of energizing capacitors
Some cable factories usually use the capacitance comparison method to find the approximate location of the broken wire in this regard. The efficiency of using continuous power supply to accurately identify the cable break point is very low. It usually takes about 1.5 hours to find a breakpoint. This method is almost impossible to find broken cores for flame-retardant cables that have already completed the shielding, armor, and sheath processes. If the workmanship is poor, it will also cause the flame-retardant cables to be scrapped. This method is basically no longer used now.
2： Combination of capacitance method and induction method:
This method is used for cable core breakage, which requires that the cable core is not covered with a metal layer and there is no extruded protective layer. When searching, first use a capacitor to find the approximate location of the cable break, and then use the induced voltage method to accurately locate the break point. This method is very simple and fast, and is currently the most commonly used method. The induced voltage method is to connect 650V AC voltage to one end of the broken core of a cable, and ground the other end and other cores. Then, use an induction pen that can emit light signals for testing. When the induction pen slides past the broken core, the signal will change, which can accurately locate the cable break point.
3： Combining constant current source and bridge method
This method is used for completed cables or cable cores that have been coated with a metal layer. The method of using is to first use a constant current source to burn and breakdown the insulation at the broken core of the flame-retardant cable, and then use a bridge fault locator to accurately locate the fault point, which is also a commonly used method.
