CN110879305A - A lightning arrester online monitoring junction box - Google Patents

Abstract

The invention relates to an electrified monitoring junction box of a lightning arrester, which comprises a box body and junction terminals, wherein an insulating plate is fixedly arranged in the box body, four junction terminals are fixedly arranged on the insulating plate, three of the four junction terminals are ABC three-phase junction terminals, the other junction terminal is a ground wire junction terminal, two junction holes are formed in the bottom of the box body, one junction hole is used for leading a lower lead of the lightning arrester into the box body and connecting the lower lead of the lightning arrester to the junction terminals, and the other junction hole is used for connecting a lead of a lightning arrester resistance current and full current tester into the box body and connecting the lower. The lightning arrester live monitoring junction box is simple in principle, convenient to install, free of influence on normal work of an original lightning arrester, and free of damage to the lightning arrester. The operation of adopting the insulator spindle overlap joint connecting wire is replaced, so that the staff is far away from the high-voltage live equipment, the lightning arrester full current and the resistive current can be safely measured, and the dangerous operation in the process of measuring the lightning arrester full current and the resistive current is avoided.

Description

A lightning arrester online monitoring junction box

technical field

The invention belongs to the field of substation operation and the field of mechanical processing, and relates to the on-line monitoring of a surge arrester, in particular to a junction box for operating a high-voltage surge arrester on-line monitoring.

Background technique

A surge arrester is an electrical appliance used to protect electrical equipment from high transient overvoltage hazards and to limit the freewheeling time and often the freewheeling amplitude. It is mainly used to protect the insulation of AC power transmission and transformation equipment from lightning overvoltage and operating overvoltage damage. The metal oxide arrester exhibits a high resistance state under normal system operating voltage, and only microampere current flows. It exhibits low resistance under the action of overvoltage and high current, thus limiting the residual voltage at both ends of the arrester. At present, the most widely used arresters are mainly zinc oxide arresters. The leakage current of zinc oxide arrester can be divided into two parts: capacitive part and resistive part.

Since MOA has good nonlinear resistance characteristics, there is no gap inside the zinc oxide arrester. It is precisely because there is no gap, the valve plate is subjected to the operation voltage of the power system for a long time in normal operation, and the internal dampness or overheating and other factors will cause the deterioration of the non-linear resistance characteristics of the valve plate. The main manifestation of this deterioration is the increase of resistive current under normal voltage, the increase of resistive current causes the increase of calorific value, the increase of the internal temperature of the arrester, and the increase of temperature accelerates the aging of the valve plate, forming a vicious circle. Finally, the MOA is damaged due to overheating, and in severe cases, it may cause the explosion of the arrester and cause a large-scale power outage. It is generally believed that the increase of the resistive current, which only accounts for 10% to 20% of the total leakage current, is the main factor causing the deterioration of the MOA. Therefore, accurately extracting the resistive current from the total leakage current is the key to judging the operating status of the MOA.

Therefore, the live monitoring of the arrester is one of the important tasks of the substation maintenance and electrical test class. Every year, the substation maintenance and electrical test class must carry out the work of detecting the resistive current of the arrester (the second work ticket).

In the multiple on-line monitoring of arresters, the joints are often in poor contact and the distance from the primary main circuit is close, which results in incorrect measurement during the resistive current detection process of the arrester, which is easy to bring danger to the measurement personnel. Therefore, the resistive current testing process of the arrester is time-consuming and labor-intensive, and there is a great danger of electric shock to the staff. At the same time, because most of the current measuring instruments are three-phase simultaneous measurement, more staff are required to participate in the measurement, and there are guardians who need to monitor multiple staff. Connecting the insulating tie rod to the lower end lead of the arrester requires complicated work steps and heavy workload, which affects work efficiency.

SUMMARY OF THE INVENTION

The purpose of the invention is to overcome the deficiencies of the prior art, to provide a lightning arrester online monitoring junction box that is easy to install and can simplify the measurement of the arrester resistive current and full current work flow, which is convenient for live detection of the arrester and avoids the contact of the arrester ground wire joint. If it is not good, keep the staff away from the live equipment during the live detection process of the arrester, reduce the risk of electric shock for the staff, reduce the wiring complexity, save manpower and improve work efficiency.

The technical scheme adopted by the present invention to solve the technical problem is:

A lightning arrester live monitoring junction box, comprising a box body, a wiring terminal, an insulating plate fixed in the box, four wiring terminals fixed on the insulating plate, three of which are ABC three-phase wiring terminals, and the other is ground wire connection Terminals, there are two wiring holes at the bottom of the box, one of which is used to introduce the lower lead of the arrester into the box and connect the wire to the terminal, and the other wiring hole is used to connect the arrester resistive current and full current The lead wire of the tester is inserted into the box and the connecting wire is connected to the terminal.

Also, the cabinet includes a cabinet door.

Moreover, the box body is connected to the arrester structure through a hoop.

The advantages and positive effects of the present invention are:

1. This arrester live monitoring junction box solves the complex problem of operation and maintenance personnel on the live monitoring of the arrester, effectively improves the efficiency of measuring the full current and resistive current of the arrester, and can change the traditional operation that requires four people to operate. Operate for two people.

2. The junction box for live monitoring of the arrester is simple in principle and easy to install. It does not affect the normal operation of the original arrester and will not cause damage to the arrester. It replaces the operation of using insulating rods to lap the connecting wires, keeps the staff away from high-voltage live equipment, can safely measure the full current and resistive current of the arrester, and eliminates the dangerous operation in the process of measuring the full current and resistive current of the arrester.

Description of drawings

FIG. 1 is an installation structure diagram of the present invention.

Detailed ways

The present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. The following embodiments are only descriptive, not restrictive, and cannot limit the protection scope of the present invention.

A lightning arrester live monitoring junction box, comprising a box body 3, a wiring terminal 4, an insulating plate, the lower end of the arrester 1 is connected to the wiring terminal inside the box body through the lead 2, and the wiring terminal is fixed on the insulating plate. There are four, three of which are ABC three-phase terminals, and the other is the ground terminal. The insulating plate is connected to the box body by bolts. The box body contains a cabinet door. The box body is connected to the arrester structure through a hoop. The installation height from the ground should be easy to operate, generally less than 1.5m. When not in use, the cabinet door should be increased. Lock.

In order to prevent rainwater from entering, two wiring holes are made at the bottom of the box, one of which is used to introduce the lower lead of the arrester into the box and connect the wire to the terminal, and the other is used to connect the resistive current of the arrester. And the 5 leads of the full current tester are connected to the box and the connecting line is connected to the terminal, and the junction box should be well grounded.

The connection between the lead wire and the arrester, and the lead wire and the terminal is tight, which meets the requirements of the "State Grid Substation Operation Management Regulations". After installing the arrester live monitoring junction box, you can directly connect the arrester resistive current and full current tester to the three terminals in the junction box, thereby effectively improving the measurement efficiency of the arrester resistive current and full current, reducing the The time of using the insulating rod to overlap reduces the time for the staff to operate near the live equipment, making the live monitoring work of the arrester safer.

The lower lead of the arrester in the junction box for live monitoring of the arrester is reliably isolated from the ground. If the junction box for live monitoring of the arrester cannot be used due to a fault, the full current and resistive current of the arrester can also be measured in a traditional way by lap connection, without affecting the moisture absorber. The measurement of full current and resistive current increases the reliability of the measurement of full current and resistive current of the arrester.

The using method of the present invention is:

In the process of measuring the full current and resistive current of the arrester, open the junction box for live monitoring of the arrester, and connect the three-phase wiring of the test instrument to the three terminals in the box, that is, the full current and resistive current of the arrester can be measured through the terminals.

The present invention has been tested in the laboratory, fully complies with the requirements in "State Grid Substation Operation Management Regulations" and "State Grid Corporation Electric Power Safety Work Regulations (Transformation Part)", and can be applied on-site.

The above are only the preferred embodiments of the present invention. It should be pointed out that for those of ordinary skill in the art, some modifications and improvements can be made without departing from the inventive concept, which belong to the present invention. protected range.

Claims (3)

1. The utility model provides an electrified junction box that monitors of arrester, includes the box, binding post, its characterized in that: an insulating plate is fixedly arranged in a box body, four wiring terminals are fixedly arranged on the insulating plate, three wiring terminals are ABC three-phase wiring terminals, the other wiring terminal is a ground wire wiring terminal, two wiring holes are formed in the bottom of the box body, one wiring hole is used for leading a lower lead of a lightning arrester into the box body and connecting the lower lead of the lightning arrester with the wiring terminals, and the other wiring hole is used for leading a lead of a lightning arrester resistance current and full current tester into the box body and connecting the lead of the lightning arrester with the wiring terminals.

2. The live lightning arrester monitoring junction box according to claim 1, characterized in that: the box body comprises a cabinet door.

3. The live lightning arrester monitoring junction box according to claim 1, characterized in that: the box passes through the staple bolt and connects on the arrester framework.

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