CN201699407U

CN201699407U - Two-stage lightening protection device of multiple-branch electric bridge

Info

Publication number: CN201699407U
Application number: CN2010202392438U
Authority: CN
Inventors: 秦亚明; 郭平
Original assignee: TIEDA TELECOMMUNICATION EQUIPMENT CO Ltd SHANGHAI
Current assignee: SHANGHAI TIEDA ELECTRONIC AND INFORMATION TECHNOLOGY CO., LTD.
Priority date: 2010-06-25
Filing date: 2010-06-25
Publication date: 2011-01-05
Anticipated expiration: 2020-06-25

Abstract

The utility model relates to a lightening protection device which is used in a railway signal system and reduces and prevents electromagnetic effect generated in the space to be protected, and particularly to a two-stage lightening protection device of multiple-branch electric bridge with branch circuits which share one main circuit at a state with multiple signal inputs. The lightning protection is divided into two stages. The first stage is gas discharge tubes FD1-FD5, and the second stage is TVS tube. Decoupling resistors R2-R5 which reduces the impact caused by surge to two-stage electric bridge and TVS tube are provided between the first stage and the second stage. The two-stage lightening protection device of multiple-branch electric bridge according to the utility model has the following advantages: improving impact throughflow capacity of lightning protection product, adoption of series connection of diode and TVS tube, capacity for reducing capacitance between two signal wires, increased communication bandwidth, reduced signal insertion loss, reduced number of components, adoption of standard interface, convenient mounting and use, low cost, convenient maintenance and improved product reliability.

Description

Multiple branch circuit electric bridge two-stage thunderstorm electricity protective device

Technical field:

The utility model relates to and is used for railway signal system, reduce and prevent the lightning protection device of lightning current galvanomagnetic effect that produces in the need protective zone, especially be under the situation of multiple signals input the multiple branch circuit electric bridge two-stage thunderstorm electricity protective device of a shared main circuit.

Background technology:

Lightning protection device is indispensable a kind of device in the electronic equipment lightning protection; its effect is that the instantaneous overvoltage of invading a power line, signal transmssion line is limited in the voltage range that equipment or system can bear; or powerful lightning current let out the inflow place, protect protected equipment or system not to be hit and damage.

The utility model content:

Concrete technical scheme of the present utility model is: a kind of multiple branch circuit electric bridge two-stage thunderstorm electricity protective device, and lightning protection divides two-stage, and one-level is gas discharge tube FD1～FD5, and secondary is the TVS pipe; Between a secondary, be provided with and reduce surge and move back lotus root resistance R 2～R5 what secondary electric bridge and TVS pipe impacted.

Further, owing to impact the big TVS of discharge capacity, its Rong Yeda that economize on electricity, it is strong and to insert loss little to reach protective capacities, can reduce the appearance of economizing on electricity greatly with diode and TVS series connection.

Further, the equivalent capacity of electric bridge is compared the economize on electricity Rong Yuanxiao of single TVS, and equivalent capacity equals the economize on electricity of single diode to be held, and holds irrelevant with the economize on electricity of TVS.This structure can greatly improve communication bandwidth.

The beneficial effects of the utility model are:

1. propose following of multiple signals input condition and need shared TVS pipe, can realize the differential mode protection between all holding wires.

2. constitute dual-electrode protecting circuit by gas discharge tube and TVS pipe, protective capacities is strong.

3. the utility model device has improved the impact discharge capacity of lightning-protected product, use the series connection of diode and TVS pipe, can reduce the electric capacity between two signal line, improve the bandwidth of communication, reduce signal and insert loss, and reduced component number, adopt standard interface, easy to install, cheap, be convenient to simultaneously safeguard, improve product reliability.

Description of drawings:

Fig. 1: the utility model principle of device schematic diagram;

Fig. 2: the utility model bridge circuit schematic diagram;

Fig. 3: the utility model electric bridge equivalent capacity schematic diagram.

Embodiment:

The utility model proposes multiple branch circuit electric bridge two-stage thunderstorm electricity protective device, be applicable to the protection of railway microelectronic device port, use this lightning protection device can minimizing equipment to avoid the overvoltage that thunder and lightning, industrial interference etc. cause and the damage of overcurrent.

A kind of multiple branch circuit electric bridge two-stage thunderstorm electricity protective device, its principle schematic as shown in Figure 1.

Lightning protection divides two-stage, and one-level is gas discharge tube FD1～FD5, can bear bigger lightning current, can carry out elementary protection to equipment in this one-level.Because one-level protection through-current capacity is big, but limit voltage ratio is higher, and response speed is slow, can only reach the effect of thick protection, for reaching meticulous protection to electronic equipment, the TVS pipe that application limitations voltage is low, through-current capacity is big, response speed is fast in the secondary protection.Between a secondary, move back lotus root resistance R 2～R5, can effectively reduce the impact of surge secondary electric bridge and TVS.

Owing to impact the big TVS of discharge capacity, its Rong Yeda that economize on electricity, it is strong and to insert loss little to reach protective capacities, can reduce the appearance of economizing on electricity, circuit such as Fig. 2 greatly with diode and TVS series connection.The economize on electricity that the equivalent capacity of electric bridge is compared single TVS is held out and away little, its equivalent capacity such as Fig. 3, the economize on electricity of suppose diode hold equal and C2=C3=C4=C5＜＜C1 of TVS, then the equivalent capacity of electric bridge is calculated as follows:

Equivalent capacity=C2//C3+C4//C5=C2.

Be the economize on electricity appearance that equivalent capacity equals single diode, hold irrelevant with the economize on electricity of TVS.This structure can greatly improve communication bandwidth.

Under multiple branch circuit protection situation, utilize Fig. 1 circuit, only need a TVS can realize that the differential mode between all holding wires protects, and then whole signal port is formed full mould protection, reach best protection effect, provide cost savings simultaneously, reduced the insertion loss.

Claims

1. a multiple branch circuit electric bridge two-stage thunderstorm electricity protective device is characterized in that lightning protection divides two-stage, and one-level is gas discharge tube FD1～FD5, and secondary is the TVS pipe; Between a secondary, be provided with and reduce surge and move back lotus root resistance R 2～R5 what secondary electric bridge and TVS pipe impacted.

2. multiple branch circuit electric bridge two-stage thunderstorm electricity protective device according to claim 1 is characterized in that, diode and TVS series connection.

3. multiple branch circuit electric bridge two-stage thunderstorm electricity protective device according to claim 1 is characterized in that, equivalent capacity equals the economize on electricity of single diode and holds.