CN2387651Y

CN2387651Y - Isolating distributing frame protector

Info

Publication number: CN2387651Y
Application number: CN 99229027
Authority: CN
Inventors: 陈晓宁
Original assignee: Individual
Current assignee: Individual
Priority date: 1999-07-29
Filing date: 1999-07-29
Publication date: 2000-07-12
Anticipated expiration: 2009-07-29

Abstract

The utility model provides an isolating distribution frame protector, which is especially used for data transmission lines. The utility model has the overvoltage and overcurrent protecting functions. The utility model comprises a discharge tube, a circuit board, a protector plug, an earthing strip, a casing. The utility model is characterized in that a data transmission line is connected in series with an isolating transformer; a discharge tube GDT is connected in parallel between lines a, b on the front side of the isolating transformer; a line a' and a line b' on the rear side of the isolating transformer are respectively connected in parallel with a surge suppressor TVS towards the ground.

Description

Isolated form distributing frame protector

The utility model relates to a kind of isolated form distributing frame protector, is applicable to that all carry out the overvoltage of the terminal equipment of transfer of data, the protection of overcurrent by telephone line.

The distributing frame protector cooperates distributing frame security personnel row to use usually, has the protection function of telephone line, can prevent the harm that overvoltage, overcurrent cause communication equipment, protection communication equipment safety.In recent years, along with increasing of non-talk business, make telephone line except original voice communication; also transmit lot of data information; to also putting on agenda of data terminal equipment, existing protector can not satisfy the needs of defencive function, the reasons are as follows:

One, for voiceband facility, its transmission signals peak value is a bell signal, be generally and exchange 75V stack-48V direct current signal, its crest voltage is about 150V, for making line transmissions interference-free, the operation voltage of protector should be higher than this voltage, and therefore, the protector operation voltage is generally adjusted and is 180V-230V.And for data transmission set, the signal of its transmission is generally the AC signal of several volts to tens volt, and withstand voltage only tens volts of some equipment interface chip adopt traditional distributing frame protector obviously improper.

Two, some user not only will prevent atmospheric over-voltages such as thunderbolt, also will prevent power-frequency overvoltages such as earth potential liter.When earth fault occurring as electric power system; it is gone into the electric current formed earth potential of ground short circuit and raises and can cause counterattack to communication equipment; its overvoltage is the amplitude height not only; and longer duration (is determined by relay protection device; be generally the hundreds of millisecond); traditional distributing frame protector mostly adopts amplitude limit type over-voltage protector, and its power frequency withstand level obviously can't be reached.

The purpose of this utility model is to avoid above-mentioned weak point of the prior art and a kind of isolated form distributing frame protector that is exclusively used in data transmission link that has overvoltage, overcurrent protection function concurrently is provided.

The purpose of this utility model can reach by following measure:

A kind of isolated form distributing frame protector, comprise discharge tube, wiring board, protector plug, earthing strip, housing, it is characterized in that on data transmission link, being in series with isolating transformer, before isolating transformer, be parallel with discharge tube GDT between a, b line, be parallel with surge suppressor TVS over the ground respectively at isolating transformer rear side a ' line and b ' line.

The purpose of this utility model can also reach by following measure:

The protector housing adopts universal protector housing, in wiring board (pcb board) is housed, isolating transformer, discharge tube GDT and surge suppressor TVS are housed on the plate, and link to each other with internal and external line by the protector plug, by earthing strip and protection link to each other.

Fig. 1 is the utility model circuit theory diagrams.

Fig. 2 is the utility model shape assumption diagram.

Below in conjunction with accompanying drawing the utility model is further described:

Isolated form distributing frame protector is made up of isolating transformer 1, discharge tube GDT2, surge suppressor TVS3, housing 7, pcb board 4 and protector plug 5, earthing strip 6.Isolating transformer 1, discharge tube GDT2, surge suppressor TVS3 are welded on the pcb board 4, are assembled in then in the housing 7, and link to each other with internal and external line by protector plug 5, link to each other with protection ground by earthing strip 6, constitute and isolate the distributing frame protector.

This protector first order protective circuit is made up of discharge tube GDT2, and when circuit generation transverse over voltage, discharge tube GDT2 conducting makes a, b line equipotential, is not damaged with the elementary winding of protection isolating transformer.

Protector second level protective circuit is made of isolating transformer 1, and this isolating transformer 1 is series on a, the b line, and its former and deputy limit umber of turn equates, between the winding of former and deputy limit, insulating between winding and iron core is enhanced, can bear 5KV voltage and does not damage.

Third level protective circuit is made of surge suppressor TVS3; surge suppressor TVS3 is parallel between a ', b ' line and the protection ground; further limit the voltage of coming on the one hand by isolating transformer 1 coupling; on the other hand; when the earth potential rising that electric power system earth fault causes; surge suppressor TVS3 makes a, b line and ground equipotential with the response of ns step velocity, and its high voltage is born by isolating transformer 1.

Discharge tube GDT2 is the diarcs discharge tube among the figure, and nominal voltage is that hundreds of Hz to tens thousand Hz, surge suppressor TVS3 nominal voltage can be adjusted according to transmission requirement and be a few V to tens V greater than 70V, isolating transformer transmission rate.

After adopting isolated form distributing frame protector; because the effect of isolating transformer 1; make that circuit and station equipment are kept apart from circuit outside the communication station; communication station equipment and outside-the station equipment are got in touch by the electromagnetic coupled mode; the atmospheric over-voltage that thunder and lightning causes all or the overwhelming majority act between the isolating transformer 1 former and deputy limit winding in the insulation; owing to do not have direct current circuit with the outer circuit in station, thereby avoid the damage equipment insulation, the protection device security.Equally, the power-frequency overvoltage that above earth potential raises and causes, owing to be equiped with surge suppressor TVS3 at earth-return, but the moment conducting makes a, b line all press with ground transient state, on its overvoltage still acts on and insulate between the isolating transformer 1 former and deputy limit winding, can guarantee equally apparatus insulatedly not to be damaged support equipment safety.

The utility model is compared with traditional distributing frame protector has following advantage:

1, the utility model is the protector that is exclusively used in data transmission link, fast response time, deboost Low, protective value is superior.

2, adopt miniature isolating transformer to make, can directly be inserted in the protection gang for distribution frame easily, overcome Traditional isolating transformer volume big, use inconvenient shortcoming.

3, can not only prevent lightning surge to the harm of equipment, also have the mistake that above earth potential raises and causes The protective capacities of voltage.

Claims

1, a kind of isolated form distributing frame protector, comprise discharge tube, wiring board, protector plug, earthing strip, housing, it is characterized in that on data transmission link, being in series with isolating transformer, before isolating transformer, be parallel with discharge tube GDT between a, b line, be parallel with surge suppressor TVS over the ground respectively at isolating transformer rear side a ' line and b ' line.

2, isolated form distributing frame protector according to claim 1; it is characterized in that the protector housing adopts universal protector housing; in wiring board is housed; isolating transformer, discharge tube GDT and surge suppressor TVS are housed on the plate; and link to each other with internal and external line by the protector plug, by earthing strip and protection link to each other.