Using a multimeter, how do you measure a broken wire?
You can turn the multimeter or other meter to resistance and then put the pens on the two ends of the wire to measure (note that the measurement is made with the power off).
1, if there is MΩ or KΩ that means the line is not working, broken.
2, if there are a few Ω or zero a few Ω, it means that the line is open, no disconnection. (Of course, the specific value according to the length of your line thickness varies, the above is for reference only)
Measured by electric pen
If the family line, the measurement of the two ends of the dark line is basically unrealistic, you can use the electric pen to detect (measured under power), the zero line is not electric, the electric pen does not light, the fire line is electric pen light, attention! At this time you can change the position of the fire line zero line connected, and then go to measure the original zero line, see if the pen is now bright, bright, then the original zero line is not broken, not bright, then, broken line.
This situation is often encountered in the installation and maintenance, let's start with a single-stranded wire, close to the multimeter can be used in the beeper file on the side of the measurement, if it is a long distance, the needle can not reach ah! Connect a line side measure; if the site does not have a ready-made line, the side measure of the wire to the power supply, must be a firewire, with 1000 ~ 500V gear, the side of the other end of the power, if the side of the voltage difference with the junction is too much or zero is clear that the middle of the wire there is a place of poor contact or with the circuit breakers! If it is a multi-stranded wire (cable) side amount according to the above method side amount is much more convenient!
Want to side to get which place is broken, need a digital display of the test pen, wire power (do not connect electrical appliances) in the wire on the outside can be sensed in the place of the break, there is a display of 110V, no power shows 0 or does not show (according to your digital display of the test pen, not the same as the same may not be the same)! Use electricity to pay attention to safety!
1, with a multimeter resistance block
2, with a multimeter wind chirp block
3, use the multimeter's voltage block
With the above 1, 2 methods, the red and black pens are connected to both ends of the wire, you can test the on-off
The third method should be connected to the power supply, the two wires were connected to zero, fire, with a red and black pens, respectively, there is no broken voltage, no voltage wire is broken!
Multimeter to determine a variety of line summary, 1 break no sound 2 break no resistance 3 break no voltage 4 break no current 5 break no signal 6 break no loop
