Chapter 23 Cable Faults

According to the scope of the power outage on the drawing, the thin monkey quickly identified several switches that could be blackout, and then drove along the cement poles to move forward, and the car stopped and stopped, seeing if there was any abnormality in the wires in the air as he walked.

It didn't take long for the cement pole to disappear, and the overhead line went directly to the ground from the air and became a cable line.

"Alas, it's really bad luck today, it is estimated that it is a cable failure!" The skinny monkey scratched his head.

Cable faults are the most troublesome faults in the distribution network because the fault point is underground, and it is impossible to judge the fault point from the outside. If the fault is as silent as it is today, it can only be done in the most primitive way, power outage and trial delivery.

The so-called power outage test delivery can be simply understood in this way. For example, if the starting point of a line is point A, the middle point is point B, and the end point is point C, then if the switch at point A trips and causes the entire line to lose power, and it is suspected that the fault point is in section AB or section BC, but it is impossible to determine which section it is, point B will be stopped first, and then the switch will be closed from point A to send power. If the switch at point A will trip after power transmission, it means that the fault is within the range of AB, and if it will not trip, it means that the fault is within the range of BC.

If the main switch of the general resident's house trips, you can also use a similar method to stop the switches of the kitchen, bathroom and lighting one by one, and then send the main switch to determine where the problem is.

Generally speaking, power companies do not like to use this method to find fault points, one is the large amount of operation and time-consuming. It should be noted that many switches are not remotely operated, and they all rely on personnel to go to the site to manually operate. Running the switch back and forth on a line is quite time-consuming. Second, such multiple test deliveries may cause multiple voltage shocks to the fault point, resulting in the fault becoming more serious, and the original two-phase short circuit may become the most serious three-phase short circuit. Even some normally normal lines may be damaged by impact. The third is that this may cause many frequent power outages for some customers, such as your home is just at the lower end of point A, so every time the power is cut off, your light bulb will keep turning on, off, on, and off.

However, when the power outage is over and the line section where the fault point is located is determined, this is only the beginning of the suffering.

Just ask, if you are sure that the fault of the tripping of your main switch is a short circuit inside the line buried in the wall in the kitchen, what should you do?

If you don't say it, either break the wall and re-bury the wire, or draw the wire from the line pipe and change the line. For families, a wire costs dozens or hundreds, plus the cost of hiring a plumber, it will be done for a few hundred yuan. However, for the power grid, the cable lines are hundreds or even thousands of meters at every turn. It's unrealistic to pull them all out and replace them, even the craziest losers can't do it. It is also unrealistic to dig up all the paths of the buried cable, so the only thing that can be done is to determine the specific location of the cable fault, and then dig up, cut off the faulty part, and reconnect the two sides.

Here, the most difficult thing is to determine the fault point.

Skinny Monkey gave a few people a little popularization of the trouble level of cable failure, and then began to report the scene to the dispatcher.

A few minutes later, the dispatcher's phone called, and the preliminary judgment was that it was indeed a power outage for trial delivery.

The skinny monkey wails and starts calling people to come and help - when the power goes out, because the switches at multiple points need to be moved, it is better to send at least two groups of people to the scene to save time. When operating, a group of people must have at least two people, one to operate and one to supervise. Therefore, it is impossible to let Lao Wu and the thin monkey go to two points separately to operate. As for Chi Maoshu and the others, they only have the right to watch. For power companies, time is money. There are hundreds or thousands of households in a community, and the loss of electricity bills for one hour is terrible. Therefore, more people must be dispatched at critical moments, even if they are on vacation at home.

On the way to the other group, the thin monkey had already received the dispatch order and drove over to operate.

The first stop was a switch in a residential power distribution room a few kilometers away, and the second was a switch on a cement pole on another street.

All kinds of tosses.

By the time Master Ye rushed over with Xu Lifeng and a few others, the thin monkey had already operated three times.

The two groups cooperated, and the dispatch order was also accurate and efficient, about an hour and a half, and finally preliminarily determined, the fault point was on a certain section of cable line about 200 meters long.

The thin monkey breathed a long sigh of relief and muttered, "It's really a toss." By the way, the people from the cable maintenance team will come over to find out the specific fault point, so you can take the opportunity to take a closer look. ”

It didn't take long for another orange tool cart to drive over, and Yan Yunchao jumped out of the car first and asked, "Hou Qing, what's the situation?" ”

As soon as the thin monkey Balabala spoke, another young man who was not tall but very energetic also stepped down from the tool cart, stopped for a while, and asked, "Are you sure this is this cable?" Then we'll start experimenting. ”

He first took a smaller box, took out an instrument with a probe, clamped the probe to the cable head, tinkered with it for a long time, and said, "There is indeed a cable fault." ”

"This is an insulation resistance detector, and the dispatch is only a preliminary conclusion that this cable is faulty, and it can only be really determined after it has been tested with an insulation resistance detector." Skinny Monkey explained.

Subsequently, the little man measured it with a multimeter and said: "High-resistance fault, troublesome, on the current impact!" ”

Several men struggled to remove a large and heavy creature from the back of the car, and then began wiring from the big creature to one end of the faulty cable. Then, the little young man took out an aluminum box from the car and carefully opened it - it was something similar to a headphone.

The little young man put this particular earphone on his head entirely, and his ears were wrapped in two sponge-like things.

Then he fiddled around with the big machine, got up, and walked down the path where the cable had been buried.

"What's the principle?" Chi Maoshu hurriedly asked Yan Yunchao: "Squad leader, explain to us." ”

"It's probably to add a current to this faulty cable, and the fault point is because the cable sheath must be damaged, and when there is current, it will crackle, and then walk over the cable path, use that headphone-like thing, you can hear the ring, and then you can confirm the fault point." Yan Yunchao said casually.

"However, the machine is too cumbersome to debug, and most people can't handle it. The squad leader of the cable maintenance class, that is, the little man, named Zheng Minzhao, can handle it. "Skinny Monkey added on the side.

There's electricity, so can't I show my skills, buddy?

Chi Maoshu was overjoyed and said, "Squad leader, my hearing is as good as my eyesight, why don't we go over and listen to it?" ”

"Haha, you kid is really, okay, let you try. But I advise you not to get your hopes up, if you can hear it with your ears, then what do you need this hundreds of thousands of machines for? Yan Yunchao smiled.

"Some people just love to show off, and they don't look at when it is, and they know that they are causing chaos!" A voice came from the side, but it was Xu Lifeng.

"If you don't like to see it, you can stop going, no one will force you!" Lian Tianpeng frowned and said, then hooked Chi Maoshu's shoulder and walked forward.

"That kid has a hole in his head, I didn't mess with him, why do you trouble me every day!" Chi Maoshu said: "Sooner or later, clean him up!" ”

"He's just jealous, he thinks he's amazing, and no one looks down on him."

The big machine sent the current down the faulty cable, Chi Maoshu took a few steps, and opened the pupil of Thor to take a look. Due to the large amount of electricity, Thor's pupils could see clearly with very little effort, and the light flashed under the cable path.

"Here it is!" The little man Zheng Minzhao suddenly shouted.

Several people hurriedly rushed over, only to hear Zheng Minzhao say: "There is an obvious discharge sound here, and the fault point is here." ”

Chi Maoshu Thunder God's pupils looked at it, hey, it's really, the brilliance here is obviously much brighter, and it's not purely streamlined, but a big mess.

Behind them, hired migrant workers rushed over with steel drills, ready to pry open the cement cover.

Over there, Chi Maoshu continued to walk forward curiously, and after walking less than thirty meters, he subconsciously opened the pupil of the thunder god and took a look, I rub it, how can there be a cloud of brilliance here, but it is much smaller than the one just now.

Could it be that there is still a fault here?

Chi Maoshu hurriedly rushed back and asked, "Squad Leader Zheng, you say, will there be multiple fault points at the same time?" ”

"It's not impossible, but it's very unlikely!" Zheng Minzhao is a person who is purely technical, and he is very cautious in his speech, and he will not say death.