CN100372251C - E1/T1 interface for implementing backup through using relay - Google Patents

E1/T1 interface for implementing backup through using relay Download PDF

Info

Publication number
CN100372251C
CN100372251C CNB2004100075926A CN200410007592A CN100372251C CN 100372251 C CN100372251 C CN 100372251C CN B2004100075926 A CNB2004100075926 A CN B2004100075926A CN 200410007592 A CN200410007592 A CN 200410007592A CN 100372251 C CN100372251 C CN 100372251C
Authority
CN
China
Prior art keywords
relay
interface
card
standby
analog signal
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related
Application number
CNB2004100075926A
Other languages
Chinese (zh)
Other versions
CN1661937A (en
Inventor
张耀文
李振亚
项能武
谢寿波
涂君
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Huawei Technologies Co Ltd
Original Assignee
Huawei Technologies Co Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Huawei Technologies Co Ltd filed Critical Huawei Technologies Co Ltd
Priority to CNB2004100075926A priority Critical patent/CN100372251C/en
Publication of CN1661937A publication Critical patent/CN1661937A/en
Application granted granted Critical
Publication of CN100372251C publication Critical patent/CN100372251C/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Images

Landscapes

  • Electronic Switches (AREA)

Abstract

The present invention relates to an E1/T1 interface for realizing backup by a relay. In order to solve the problems that the analog part and the digital part of the existing E1/T1 interface are not separated, and E1/T1 interface backup is not supported, the digital circuit and the active circuit of the interface are integrated on a front inserting plate in the present invention, and the analog circuit and the passive circuit of the interface are integrated on a back inserting plate; a backup scheme is adopted for the digital part and the active part of the interface, which are the most easily damaged; once the main front inserting plate of the interface is damaged, the backup front inserting plate of the interface automatically takes over operation so as to enhance the reliability of the interface and greatly enhance system stability. The design philosophy of the separation between analog and digital is adopted, and passive devices such as protective devices, transformers, etc. are arranged on the back inserting plate, and are generally not damaged; therefore, the back inserting plate doesn't need to be replaced in general, and only the front inserting plate needs to be replaced, so bound cables can not be influenced. Besides, the automatic main/backup switching mode greatly enhances the lightning proof performance of the whole interface so as to avoid major accidents such as a breakdown, etc. and reduce maintenance cost at the same time.

Description

A kind of E1/T1 Interface that adopts relay to realize backup
Technical field
The present invention relates to be used for the E1/T1 Interface (expression E1 interface or T1 interface) of the communications field, more particularly, relate to a kind of E1/T1 Interface that adopts relay to realize backup.
Background technology
E1 and T1 are respectively the abbreviations to three kinds of different systems PCM30, PCM24 of basic group in PCM (pulse code modulation) digital system.Wherein, the nominal rate of E1 is 2048kbit/s, and the nominal rate of T1 is 1544kbit/s, and detailed definition can be with reference to ITU-T standard G.703/G.704.
In traditional design, adopt the subrack design of inserting before being applicable to, and the numerical portion and the modulus part of E1 or T1 interface all is integrated on the veneer.Veneer itself is outgoing interface not, but interface is placed on the backboard, and adopts the SMB outlet method.This is a kind of comparatively ancient outlet method, no longer adopts in general new product; Its shortcoming is can't intensive outlet, does not analog-and digital-ly separate, and does not support the E1/T1 Interface backup.
In a kind of comparatively novel outlet method that more generally adopts at present, the numerical portion of E1/T1 Interface and modulus part all are integrated on the veneer.Outgoing interface on the panel of veneer, outlet method is a lot, can adopt the SMB outlet method, also can adopt outlet methods such as DB100, DB50, DB25.Insert before being applicable to or the slotting subrack design in front and back.The shortcoming of this outlet method is that its simulation part is not separated with numerical portion, and does not support the E1/T1 Interface backup.
Summary of the invention
At the above-mentioned defective of prior art, the present invention will solve the E1/T1 Interface backup is not separated and do not supported to the simulation part that has E1/T1 Interface now with numerical portion problem.
For solving its technical problem, the invention provides a kind of E1/T1 Interface that adopts relay to realize backup, wherein, the numeral of described E1/T1 Interface, active circuit are integrated on the front card, and simulation, passive circuit then are integrated on the back card/back board; Described front card comprises can realize identical function, active and standby master with relation uses front card and standby front card each other; At each the root analog signal line that needs on the described back card/back board to be connected with front card, being respectively equipped with one can optionally use the analog signal line of back card/back board and current operate as normal main or the analog signal selection circuit of the corresponding analog signal line connection of standby front card by relay.
Among the present invention, also be provided with the control Driver Circuit that to send the controlling and driving signal according to the relay of control signal in described analog signal selection circuit that the master uses or standby front card is exported of current operate as normal.During specific design, described analog signal selection circuit is located on the described back card/back board; Described control Driver Circuit comprises main control Driver Circuit and the standby control Driver Circuit used, and primary, spare control Driver Circuit can be located on the described back card/back board simultaneously, also can be located at main with on front card and the standby front card respectively.Can adopt triode, metal-oxide-semiconductor or Darlington transistor as driver in the described primary, spare control Driver Circuit.
In a preferred version of the present invention, described relay adopts solid-state relay, each root analog signal line of described back card/back board is connected to active/standby corresponding analog signal line with front card by an active/standby pair of contact with solid-state relay at least, and described active/standby control end with solid-state relay is connected to described active/standby output with control Driver Circuit.The control signal that described master exports with front card is connected to the base stage of a triode Q1, and the emitter of triode Q1 is to main control end output controlling and driving signal with solid-state relay; The control signal of described standby front card output is connected to the base stage of another triode Q2, and the emitter of triode Q2 is to the control end output controlling and driving signal of standby solid-state relay.
In another preferred version of the present invention, described relay adopts time pulse relay, each root analog signal line of described back card/back board is connected to active/standby corresponding analog signal line with front card by an active/standby pair of contact with time pulse relay at least, and described active/standby control end with time pulse relay is connected to described active/standby output with control Driver Circuit.Also can adopt the time pulse relay that to accept positive and negative pulse simultaneously as a primary, spare time pulse relay of analog signal line; Described main controlling and driving holding wire with control Driver Circuit is connected with the control end of described time pulse relay and to described time pulse relay output direct impulse controlling and driving signal, the controlling and driving holding wire of described standby control Driver Circuit is connected with the control end of described time pulse relay and exports reverse impulse controlling and driving signal to described time pulse relay; The corresponding analog signal line of described primary, spare front card is connected respectively to the forward and reverse input contact of described time pulse relay, and is connected to corresponding analog signal line on the back card/back board through same output contact.
The present invention is to the numeral of easy damage, active part adopt backup scenario in E1 or the T1 interface, in case the master of E1 interface damages with front card, its standby front card can be devoted oneself to work automatically, thereby has strengthened the reliability of E1 interface, has promoted the stability of system greatly.Because the design philosophy that has adopted modulus to separate, passive devices such as protection device, transformer are placed on the back card/back board, generally can not damage, so back card/back board generally need not change, and only need to change front card, so the cable of tying up can be not influenced.In addition, this active and standby mode with automatic switchover improves the anti-thunderbolt performance of whole E1 interface greatly, has avoided major accidents such as paralysed machine, has reduced maintenance cost simultaneously.
Description of drawings
The invention will be further described below in conjunction with drawings and Examples, in the accompanying drawing:
Fig. 1 is the catenation principle figure between primary, spare front card and the monolithic back card/back board among the present invention;
Fig. 2 is the catenation principle figure between primary, spare front card and two back card/back boards among the present invention;
Fig. 3 is the schematic diagram of solid-state relay used in the embodiment of the invention one;
Fig. 4 is the analog signal line annexation schematic diagram between primary, spare front card and the back card/back board in the embodiment of the invention one;
Fig. 5 is the control signal wire annexation schematic diagram between primary, spare front card and the back card/back board in the embodiment of the invention one;
Fig. 6 is the schematic diagram of time pulse relay used in the embodiment of the invention two;
Fig. 7 is the analog signal line annexation schematic diagram between primary, spare front card and the back card/back board in the embodiment of the invention two;
Fig. 8 is the control signal wire annexation schematic diagram between primary, spare front card and the back card/back board in the embodiment of the invention two.
Embodiment
For ease of describing, below only be that example describes, but all schemes are all applicable to the T1 interface with E1.
According to the information of Market Feedback, the E1 interface damages and belongs to one of ratio soprano in the single board default.Because the E1 interface damages, and not only needs to spend a large amount of maintenance costs, even bring great accident may for office side.If there is veneer to damage, general treating method is to change plate, but changing plate must influence the E1 cable of having tied up, and all is inadvisable from engineering and reliability angle.
For improving its reliability, adopt among the present invention that mutually redundant mode designs the E1 interface between plate, in case certain piece E1 interface single plate damages, do not change under the prerequisite of distribution in assurance, system can be with E1 interface auto switching to standby interface single plate, thereby strengthen the reliability of E1 interface, greatly the stability of elevator system.
For the E1 interface, what spoilage was the highest is the numerical portion of interface, and the spoilage of passive devices such as transformer, protection device is much smaller relatively.So, the theory that the present invention separates according to modulus, the E1 interface is divided into two parts, as shown in Figure 1, wherein numeral, active part are integrated into front card, and simulation, passive part then are integrated into back card/back board, and only numeral, active part are established primary and backup veneer, that is to say, be provided with a main front card 11 and the standby front card 12 used.The circuit of primary, spare front card and structure all are identical, can finish identical functions, but in use by corresponding setting and active and standby each other with relation, that is to say that arbitrary in two front cards can be as main usefulness, and another piece is then as standby.Be main with front card 11 work under the normal condition, standby front card 12 is not worked; When the master is broken down with front card, just replace its work by standby front card.During specific design, can primary, spare front card be set by toggle switch or alternate manner separately, and start or stop the work of standby front card by interconnective holding wire, as shown in Figure 5, when the master is broken down with front card 11, to send a corresponding active and standby signal to standby front card 12, standby front card is started working; Recover just often with front card 11 when main, will send a corresponding active and standby signal, standby front card is quit work to standby front card 12.
As for back card/back board, as shown in Figure 1, simulation, active part can be integrated on the same veneer, promptly have only a back card/back board 2.For with the respective outer side edges of two front cards 11,12, also simulation, passive part can be located at respectively on two back card/back boards 21,22, as shown in Figure 2, but this is a kind of physical division of back card/back board, not active and standby between two back card/back boards 21,22, but work simultaneously to finish a total function with relation.
As can be seen, the connecting line between primary, spare front card and the back card/back board comprises the analog signal line (i.e. two-way hollow arrow line among the figure) of E1 interface and is used for realizing the control signal wire (i.e. the unidirectional filled arrows line of figure) of primary, spare selection from Fig. 1 and Fig. 2.
Wherein, E1 interface analog signal line is provided to back card/back board respectively by primary, spare front card: if between front card and the back card/back board N road E1 interface is arranged, then need 4*N bar line; Correspondingly, every back card/back board is connected with primary, spare two front cards respectively, supports 2*N road E1 interface, needs 8*N bar line.
Control signal wire is also provided to back card/back board respectively by primary, spare front card, specifically is that front card by current operate as normal provides control signal to back card/back board, with the master that selects to connect current operate as normal with front card or standby front card.The quantity of control signal wire is different and different according to design.
Among the present invention, needing control signal wire to select the E1 interface analog signal line of corresponding front card, is the HDB3 sign indicating number because E1 interface analog signal line walks, and common selector can't satisfy its functional requirement.Use solid-state relay or time pulse relay as selector switch among the present invention, describe respectively below in conjunction with specific embodiment.
One, adopt solid-state relay to realize backup
The theory structure of solid-state relay as long as add certain controlling and driving signal at A, B end, just can be controlled " leading to " and " breaking " between C, the D two ends during work as shown in Figure 3, realizes the function that switch is selected; Because the application of optical coupler, the required power of its control signal extremely low (but surplus in the of about ten milliwatt just operate as normal).
1, E1 interface analog signal line
As shown in Figure 4, in the present embodiment, adopting solid-state relay to control the break-make between the corresponding analog signal line on the front card each root analog signal line and primary, spare on the back card/back board 2.
When the master used front card 11 operate as normal, standby front card 12 was not worked, and main control signal with front card 11 outputs makes relay J 11, J12 closure; Standby front card 12 is not exported control signal, or the output control signal disconnects relay J 21, J22.Thereby make main analog signal form a loop, thereby the analog signal line of back card/back board 2 is connected with main corresponding analog signal line with front card 11 through J11, T1, J12 with front card.
When the master is broken down with front card 11, will devote oneself to work by standby front card 12, the control signal of standby front card 12 outputs makes relay J 21, J22 closure; The master does not export control signal with front card 11, or the output control signal disconnects relay J 11, J12.Thereby make the analog signal of standby front card form a loop, thereby the analog signal line of back card/back board 2 and the corresponding analog signal line of standby front card 12 are connected through J21, T1, J22.
As seen, active and standby selection circuit shown in Figure 4 can realize that back card/back board 2 is connected with selection between the primary, spare front card 11,12.What illustrate among the figure is the schematic diagram that single channel E1 receives (perhaps sending) holding wire, needs 4 solid-state relays altogether.
2, control signal wire
In the present embodiment, control signal adopts the triode drive scheme, and the triode driver is placed on the front card.As shown in Figure 5, because the driving force of triode is relatively large, an available triode drives a plurality of solid-state relays.This programme is fit to the various density outlet schemes of E1 interface.
When the master used front card 11 operate as normal, main control signal with front card 11 outputs made triode Q1 conducting, drives relay J 11, J12 closure again; This moment, standby front card 12 was not worked, and relay J 21, J22 are off-state.
When the master is broken down with front card 11, will devote oneself to work by standby front card 12, the control signal of standby front card 12 outputs makes triode Q2 conducting, drives relay J 21, J22 closure again; Relay J 11, J12 are off-state at this moment.
In addition, the driver among Fig. 5 can be selected common triode driver for use, also can select for use metal-oxide-semiconductor, Darlington transistor etc. as driver; And, also driver can be placed on the back card/back board.
Two, adopt time pulse relay to realize backup
The theory structure of used time pulse relay when when A, B end adds a direct impulse controlling and driving signal, can make between C11 and D1, C12 and the D2 and connect as shown in Figure 6 in the present embodiment; When A, B end adds a reverse impulse controlling and driving signal, can make between C21 and D1, C22 and the D2 and connect, realize the function that switch is selected.
1, E1 interface analog signal line
As shown in Figure 7 and Figure 8, in the present embodiment, adopting time pulse relay to control the break-make between the corresponding analog signal line on the front card each root analog signal line and primary, spare on the back card/back board 2.
When the master used front card 11 operate as normal, standby front card 12 was not worked, and main direct impulse control signal with front card 11 outputs makes between C11 and D1, C12 and the D2 to be connected; Thereby the analog signal line of back card/back board 2 is connected with main corresponding analog signal line with front card 11.
When the master is broken down with front card 11, will devote oneself to work by standby front card 12, the reflected impulse control signal of standby front card 12 outputs makes between C21 and D1, C22 and the D2 to be connected; Thereby the analog signal line of back card/back board 2 and the corresponding analog signal line of standby front card 12 are connected.
As seen, active and standby selection circuit shown in Figure 7 can realize that back card/back board 2 is connected with selection between the primary, spare front card 11,12.
2, control signal wire
In the present embodiment, control signal adopts the triode drive scheme, and the triode driver is placed on the front card.As shown in Figure 5, because the driving force of triode is relatively large, available a pair of triode drives a plurality of time pulse relays.This programme is fit to the various density outlet schemes of E1 interface.
When the master used front card 11 operate as normal, main control signal with front card 11 outputs made triode Q11, Q12 conducting, thereby to time pulse relay output direct impulse controlling and driving signal, made between C11 and D1, C12 and the D2 and connect.
When the master is broken down with front card 11, to devote oneself to work by standby front card 12, the control signal of standby front card 12 outputs makes triode Q21, Q22 conducting, thereby to time pulse relay output reverse impulse controlling and driving signal, makes between C21 and D1, C22 and the D2 and connect.
In addition, the driver among Fig. 8 can be selected common triode driver for use, also can select for use metal-oxide-semiconductor, Darlington transistor etc. as driver; And, also driver can be placed on the back card/back board.

Claims (9)

1. an E1/T1 Interface that adopts relay to realize backup is characterized in that,
The numeral of described E1/T1 Interface, active circuit are integrated on the front card, and simulation, passive circuit then are integrated on the back card/back board;
Described front card comprises can realize identical function, active and standby master with relation uses front card and standby front card each other;
Wherein, at each the root analog signal line that needs on the described back card/back board to be connected with front card, being respectively equipped with one can optionally use the analog signal line of back card/back board and current operate as normal main or the analog signal selection circuit of the corresponding analog signal line connection of standby front card by relay.
2. employing relay according to claim 1 is realized the E1/T1 Interface of backup, it is characterized in that, wherein also be provided with the control Driver Circuit that to send the controlling and driving signal according to the relay of control signal in described analog signal selection circuit that the master uses or standby front card is exported of current operate as normal.
3. employing relay according to claim 2 is realized the E1/T1 Interface of backup, it is characterized in that described analog signal selection circuit is located on the described back card/back board, and described control Driver Circuit comprises main with control Driver Circuit and standby control Driver Circuit.
4. employing relay according to claim 3 is realized the E1/T1 Interface of backup, it is characterized in that described primary, spare control Driver Circuit can be located on the described back card/back board simultaneously, also can be located at main with on front card and the standby front card respectively.
5. employing relay according to claim 4 is realized the E1/T1 Interface of backup, it is characterized in that, adopts triode, metal-oxide-semiconductor or Darlington transistor as driver in the described primary, spare control Driver Circuit.
6. according to the E1/T1 Interface of claim 4 or 5 described employing relays realization backups, it is characterized in that described relay is a solid-state relay,
Each root analog signal line of described back card/back board is connected to main corresponding analog signal line with front card by a master with the pair of contact of solid-state relay at least, and described main control end with solid-state relay is connected to the described main output of using control Driver Circuit;
Each root analog signal line of described back card/back board is connected to the corresponding analog signal line of standby front card at least by the pair of contact of a standby solid-state relay, the control end of described standby solid-state relay is connected to the output of described standby control Driver Circuit.
7. employing relay according to claim 6 is realized the E1/T1 Interface of backup, it is characterized in that, the control signal that described master exports with front card is connected to the base stage of a triode driver Q1, and the emitter of triode Q1 is to main control end output controlling and driving signal with solid-state relay; The control signal of described standby front card output is connected to the base stage of another triode driver Q2, and the emitter of triode Q2 is to the control end output controlling and driving signal of standby solid-state relay.
8. employing relay according to claim 4 is realized the E1/T1 Interface of backup, it is characterized in that described relay is a time pulse relay,
Each root analog signal line of described back card/back board is connected to main corresponding analog signal line with front card by a master with the pair of contact of time pulse relay at least, and described main control end with time pulse relay is connected to the described main output of using control Driver Circuit;
Each root analog signal line of described back card/back board is connected to the corresponding analog signal line of standby front card at least by the pair of contact of a standby time pulse relay, the control end of described standby time pulse relay is connected to the output of described standby control Driver Circuit.
9. employing relay according to claim 8 is realized the E1/T1 Interface of backup, it is characterized in that, at each root analog signal line of described back card/back board, adopt the time pulse relay that to accept positive and negative pulse simultaneously as a primary, spare time pulse relay of analog signal line;
Described main controlling and driving holding wire with control Driver Circuit is connected with the control end of described time pulse relay and to described time pulse relay output direct impulse controlling and driving signal, the controlling and driving holding wire of described standby control Driver Circuit is connected with the control end of described time pulse relay and exports reverse impulse controlling and driving signal to described time pulse relay; The corresponding analog signal line of described primary, spare front card is connected respectively to the forward and reverse input contact of described time pulse relay, and is connected to corresponding analog signal line on the back card/back board through same output contact.
CNB2004100075926A 2004-02-25 2004-02-25 E1/T1 interface for implementing backup through using relay Expired - Fee Related CN100372251C (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CNB2004100075926A CN100372251C (en) 2004-02-25 2004-02-25 E1/T1 interface for implementing backup through using relay

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CNB2004100075926A CN100372251C (en) 2004-02-25 2004-02-25 E1/T1 interface for implementing backup through using relay

Publications (2)

Publication Number Publication Date
CN1661937A CN1661937A (en) 2005-08-31
CN100372251C true CN100372251C (en) 2008-02-27

Family

ID=35011040

Family Applications (1)

Application Number Title Priority Date Filing Date
CNB2004100075926A Expired - Fee Related CN100372251C (en) 2004-02-25 2004-02-25 E1/T1 interface for implementing backup through using relay

Country Status (1)

Country Link
CN (1) CN100372251C (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN100440845C (en) * 2006-05-26 2008-12-03 华为技术有限公司 Method and system for reversing main-equipment with interconnected single-board
CN100479341C (en) * 2006-07-21 2009-04-15 华为技术有限公司 A device and method for the E1/T1 interface backup
CN101146144B (en) * 2007-10-11 2010-06-23 中兴通讯股份有限公司 E1/T1 interface circuit and E1/T1 interface circuit device with master/slave structure

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4328577A (en) * 1980-06-03 1982-05-04 Rockwell International Corporation Muldem automatically adjusting to system expansion and contraction
EP1133197A1 (en) * 2000-03-08 2001-09-12 Tenovis GmbH & Co. KG Switching device
CN2517181Y (en) * 2001-11-27 2002-10-16 北京格林威尔科技发展有限公司 Optical transmission device with multi-data interface
CN1409560A (en) * 2001-09-27 2003-04-09 阿尔卡塔尔加拿大公司 System for providing structure movement exchanging control in communication system

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4328577A (en) * 1980-06-03 1982-05-04 Rockwell International Corporation Muldem automatically adjusting to system expansion and contraction
EP1133197A1 (en) * 2000-03-08 2001-09-12 Tenovis GmbH & Co. KG Switching device
CN1409560A (en) * 2001-09-27 2003-04-09 阿尔卡塔尔加拿大公司 System for providing structure movement exchanging control in communication system
CN2517181Y (en) * 2001-11-27 2002-10-16 北京格林威尔科技发展有限公司 Optical transmission device with multi-data interface

Also Published As

Publication number Publication date
CN1661937A (en) 2005-08-31

Similar Documents

Publication Publication Date Title
DK0749663T3 (en) Telecommunication switch with improved redundancy
CN100372251C (en) E1/T1 interface for implementing backup through using relay
US6603736B1 (en) Communication device for transmitting message signals
CN100353680C (en) Device of implementing backup for communication equipment in multistage and method of rearranging main and standby devices
EP0332199A2 (en) Transmission line switching system
CN203117691U (en) An intelligent power module and a high-voltage power switch
KR101125685B1 (en) Reliable DC power supply
CN100479341C (en) A device and method for the E1/T1 interface backup
CN201315486Y (en) Module for redundancy logical switch in direct current power transmission system
CN101335458B (en) Periphery module and periphery system for an automation system
CN100440845C (en) Method and system for reversing main-equipment with interconnected single-board
CN101170780B (en) Method for dual mode terminal to prevent from current backflow between two radio modules
CN101521503A (en) Circuit and method for signal voltage transmission within driver of power semiconductor switch
WO2003081941A3 (en) Optical switching station and connection method for the same
CN100514877C (en) Spare system, method and its back board of relay interface
CN1471243A (en) Two-way optical communication apapratus capable of automatically realizing main-backup change
CN216086256U (en) Automatic power switching system
CN102694719A (en) Micro telecommunication computing architecture (micro TCA) system, carrier hub module and port configuration method of peripheral component interconnect (PCI)-E exchanger
CN101188437B (en) A method for realizing switching status inquiry upon channel switching based on hardware
KR200346342Y1 (en) AC/DC Power switching apparatus for mobile communication repeater
CN204928135U (en) A distributed control device for high -pressure active filter
CN115694439A (en) Automatic starting circuit and control method thereof
CN113608488A (en) Control assembly for discharging device
JP4471188B2 (en) Control signal output circuit from computer system
JPH07177225A (en) Backup system for switch package

Legal Events

Date Code Title Description
C06 Publication
PB01 Publication
C10 Entry into substantive examination
SE01 Entry into force of request for substantive examination
C14 Grant of patent or utility model
GR01 Patent grant
CF01 Termination of patent right due to non-payment of annual fee

Granted publication date: 20080227

CF01 Termination of patent right due to non-payment of annual fee