NTP It is necessary for time synchronization server to apply hospital information system
NTP It is necessary for time synchronization server to apply hospital information system
1.1.1. System Overview
For hospitals 、 campus 、 The clock system products of traffic engineering must be accurate 、 Security 、 reliable . On the basis of summing up the experience of clock system production in the company and its counterparts at home and abroad for many years , We adopt the design ideas of system theory and process theory , Apply the advanced communication and computer technology in the world , Distributed architecture , Designed with distributed control 、 Dual hot backup 、 Automatic switching protection 、 It has high accuracy and reliability , Advanced technology 、 High quality large area slave clock system . All the equipment provided in this technical proposal are self-developed products of the company , Components and components used in system equipment （ except CUP Beyond the individual components of the chip ）, The vast majority of equipment and components are selected from domestic well-known brands , In soft 、 The design of hardware follows the principle of both advanced and reliable , Consider the complex environmental conditions of each site , In the product design, the environmental differences between the South and the north and the architectural styles are fully considered , The design and internal and external protection of products are fully prepared and considered , In particular, the appearance design of the bell is in harmony with the decoration design style on site , To achieve the perfect combination of function and perception .
Clock system is an indispensable and important part of engineering system , Its main function is to provide a standard and unified time information for system staff and people , At the same time, it provides a unified standard time signal for other relevant operation system equipment of each department to synchronize with the system , So as to realize the time standard unification of the Department and its whole network . It plays an important role in the service quality of the system .
The principle of clock system is to receive by master clock GPS/ Time information of Beidou satellite , The master clock and NTP Ethernet interface provides unified standard time signal for other systems , Make network other communication system equipment and LAN server 、 Computer workstation and clock system time synchronization , Thus, the unified time standard of the whole network can be realized .
1.1.2. Key points of system design
① All the equipment in this system can meet the requirements of daily 24 Hours of uninterrupted continuous operation .
② The system can be monitored , By setting the monitoring computer in the campus control center, it can real-time monitor the running state of the main equipment of the clock system and the synchronization of the campus clock .
③ The system design adopts distributed structure , The system consists of a master clock （Zigbee Wireless interface 、 Multi channel serial output interface device 、NTP Network timing interface ） Slave clock and transmission channel etc . The campus clock is independent of the upper network , The slave clock time can be controlled independently , Again NTP The server can also be independent of the upper network and can provide standard time signals to the network .
④ The network master clock receives the upper network standard time or the local station GPS/ Beidou satellite standard time signal , Time code generation . use Zigbee The wireless communication interface communicates with the slave clock of the station and other systems . In order to ensure that the whole network system time and the upper network or satellite standard time strictly synchronized .
⑤ Green environmental protection design concept promotion and whole process control 、 Selection and use of low energy consumption components 、 Application of low energy and long life luminescent materials 、 The use of new durable materials 、 Introduction and application of advanced VLSI technology , The overall energy consumption of the clock system is greatly reduced , It improves the service life of the clock system , And reduce the cost of use .
⑥ In order to improve the reliability of the system , The system adopts closed-loop control , Implement isolation technology 、 Power down protection 、 Software self diagnosis measures, etc , The software and hardware design adopts large redundancy .
⑦ The design of this system follows the mature 、 accurate 、 Simple 、 reliable 、 Easy to expand 、 The principle of easy management , To ensure the safety of long-term operation 、 Reliable and low cost . At the same time, it is easy to manage and expand , And maintained the advanced nature in a certain period .
⑧ The design of this system fully considers the characteristics of high-speed rail traffic , Special attention is paid to the interference of electromagnetic wave generated by electromagnetic motor on clock system , Anti electromagnetic 、 Electrical interference resistant equipment and cables , And take the necessary protective measures .
⑨ The system can be easily extended and upgraded , Changes to the campus master clock system of each node will not affect the whole system .
1.1.3. System composition
126.96.36.199. System structure diagram
188.8.131.52. system function
Synchronous proofreading function :
The network master clock receives from the upper network （ Master clock ） Clock source standard time （ Main external clock source ） Or this site set up GPS/ Beidou time code signal （ Standby external clock source ）, To calibrate its own internal clock accuracy , With the upper network standard time and this site GPS/ Beidou standard time keeps in sync . Network master clock in the upper network and GPS/ After the Beidou signal fails at the same time , The master clock automatically switches to the master clock which is stable in height .
Time to show ：
The master clock is on time ： branch ： Show time in seconds ; The digital slave clock is ： branch ： Second display （ Or you can choose to display with date ）. Date display ：
The master clock can show the year 、 month 、 Japan 、 week 、 when 、 branch 、 Second and other full time scale time information , It can display the operation information of the loaded slave clock .
Provide standard time signal for other systems ：
The master clock is equipped with NTP Ethernet interface output interface , Ethernet (NTP agreement ) Interface signal to other system equipment .
System hot backup function ：
The master clock is owned by the master 、 Standby master clock consists of , With hot backup function , When the master clock fails , The system can immediately detect and automatically switch to the standby master clock , The standby master clock completely replaces the main master clock , When the master and master clocks return to normal , The standby master clock switches back to the main master clock immediately .
Network master clock function ：
The main and standby signal processing unit of network master clock is the central part of the whole campus clock system , The stability of its work largely determines the reliability of the whole system , So it's mainly designed 、 Dual system mode of standby machine configuration , Lord 、 The standby machine has the function of self check and mutual check , And 、 Automatic or manual switching between standby machines can be realized . The output of network master clock is digital signal , In line with industry standards and ITU （ITU） Relevant specifications .
⑴ Network master clock can display year 、 month 、 Japan 、 week 、 when 、 branch 、 Second and other full time scale time information .
The network master clock panel indicator displays the following information ：
ⅰ.GPS/ Effective number of Beidou data
ⅱ. The upper network data is valid indication
ⅲ. Power condition
ⅳ. With YY-MM-DD（ year - month - Japan ） Format displays the date of the clock output
ⅴ. With HH-MM-SS（ when - branch - second ） The format shows the output time of the clock device , Can be found in 12 Hours and 24 Hour switching between the two formats .
ⅵ Local fault alarm indicator
The network master clock has the following alarm output ,
ⅰ.GPS/ Beidou signal failure
ⅱ. BITS Fault signal
ⅲ. Output failure
ⅳ. Power failure
Ⅴ. Subsystem failure
⑵ Network master clock and GPS/ Beidou or upper network standard time keeps synchronization .
⑶ The network master clock can realize the unified adjustment of time through the keyboard set on the front panel with lock .
⑷ Network master clock can receive aquatic seedlings and GPS/ Beidou time signal . But when the external clock source fails or the time signal is interrupted , The fax democratic master clock enters immediately after judgment and confirmation “ Free running ” Pattern , The process of judging the effectiveness of an external clock source does not exceed 5 Second . When in free running mode , The master clock is based on the last received upper network or GPS/ Beidou signal is used to generate time information for reference time , During an external signal interruption , The network master clock continues to work independently , The time signal produced by its own highly stable crystal oscillator is used as the time reference , With “ Independent operation ” mode , Keep its own and its subsidiary systems continuous . At the same time, it will send alarm to clock system maintenance terminal and dispatching center of Wuhan Guangzhou line .
⑸ The network master clock has a unified adjustment of the start time 、 Change the clock speed function .
⑹ Through the data channel provided by the transmission cable, the network master clock receives the operation status information from the campus master clock and its slave clock through the shunt output interface box .
⑺ The network master clock has the function of setting summer time and timing switching , This function mainly considers the need of implementing daylight saving time in the future , It's usually closed , It can be activated immediately when needed , To avoid human intervention .
⑻ The network master clock can detect the frequency fluctuation of the power grid in real time , When the frequency fluctuates too much , An alarm can be sent to remind the equipment manager to take necessary measures .
⑼ Network master clock passed standard RS232/422 The interface is connected with the maintenance terminal of the dispatching center or the centralized alarm network management of the monitoring center of the Ministry of railways , In order to realize the monitoring of the main equipment and components of the clock system .
⑽ Network master clock through 10 Road standard RS422/485 Interface , To the operational organization 、 Passenger transport management department 、 Campus and signals 、 Business phone system 、 Private telephone system 、 Wireless systems 、 broadcasting system 、AFC System 、 Recording system 、PIS System 、 signalling system 、MCS Systems and SCADA The system and other subsystems that need to unify time send the full time scale time signal , In order to realize the strict unification of the time of each communication subsystem .
⑾ Network master clock through the master 、 Cycle self check and mutual check of working state of standby master clock , When the fault is found, the master clock can be realized immediately 、 Automatic conversion of standby machine , Ordinary Lord 、 The standby master clock can also be converted manually .
⑿ System working time ：25 year ×365 God ×24 Work continuously for hours . Without amplifier and relay, the common five categories are adopted UTP transmission , The limit line distance of the driving sub clock of the campus master clock is 1500 rice （ Fiber optic transmission is not limited by distance ）.
The slave clocks of each network pass through NTP Interface , Direct cable is used to connect to the campus master clock in a point to multipoint manner , Receive the synchronous time signal sent by the campus master clock , Calibrate your own internal clock , Direct time information to staff and passengers . The slave clock receives the standard time signal , Send back its working status to the campus master clock .
The slave clock is not directly connected to the campus power supply system, which is provided by the campus master clock in a point-to-point manner 220V The ac power . Each sub clock lights up the... On the clock panel LED Indicator light , Indicates that the correct control data has been received , And has been synchronized with the campus master clock .
When the slave clock receives an effective control signal from the local campus master clock , Its time error with the campus master clock should not exceed 10 subtle .
All sub clocks have independent timing function , Track the work of campus master clock . When the campus master clock fails or for other reasons , When the synchronous time signal is not received , The slave clock can still work on its own crystal oscillator , And pass RS422 The interface sends alarm information to the upper network or campus master clock .
When the signal is interrupted , The bell will enter “ Free running ” Pattern ,LED The light goes out . After receiving valid control data again , The slave clock will be calibrated automatically . The digital slave clock is calibrated in 1 seconds , The longest time tracking distance of analog slave clock is 6 Hours （ It's possible to turn forward and reverse ）, Press 60 Double speed requires 6 Minutes to complete the chase . Unless the slave clock fails , No manual adjustment of display time is required .
The slave clock used in this project is digital slave clock and analog slave clock. All embedded slave clocks are embedded in the guiding screen of campus platform and station hall , Open a window on it according to the size given by the clock system , The slave clock is embedded in the window as a closed independent module , The power line and signal line are introduced separately .
All slave clocks have a memory function , Built in real-time clock IC and rechargeable battery , Real time data can be kept for ten years after power failure , After the call, the digital slave clock will automatically refresh and display the correct time , The analog slave clock automatically enters the time tracking program , Automatically calculate and select the shortest path to dial or reverse , With 60 Speed up to the right time and then run normally .
Under all kinds of light conditions （ For example, strong direct sunlight ）, All the slave clocks are clearly visible .
The shell of the slave clock is made of stainless steel or aluminum , See the appearance drawing for the design effect of bell shield , The design meets the requirements of the specification , Fully consider the visual impact of the slave clock and the slave clock box in the campus . The chassis design also takes into account the ergonomic factors and the overall coordination with the campus design .
The color selection range of the bell cover is unlimited , It can be made according to the color code required by the owner . The color selection will be decided by the owner during the design liaison .
All bell guards are equipped with shatter proof 、 Anti reflective glass or hemp panel .
Maintain terminal functions
Clock system monitoring management for each campus PC The machine is the maintenance terminal , System performance management can be carried out 、 Configuration Management 、 fault management 、 security management . Monitoring software uses VisualBasic6.0 Made up of , To run on WINDOWS XP HOME operating system . The monitoring interface is displayed in Chinese 、 Drop down menu mode , It has a friendly man-machine interface 、 Good openness and extensibility . It is convenient to add, delete and change the number of master clocks and slave clocks that need to be monitored . It passes the standard RS232/422 The interface is connected to the upper network , It has centralized maintenance and self diagnosis function .
The maintenance terminal can detect the operation status of the main equipment of the railway campus level clock system in real time , The working state of the system 、 The fault status is displayed 、 Print 、 The archive , And can control the whole line clock point to point , The main monitoring and display contents include ：
⑴ The upper net and GPS/ Receiving status of Beidou signal
⑵ Working state of signal processing unit
⑶ Campus clock 、 The working state of each slave clock
⑷ Output the working state of the interface
⑸ The working state of the transmission channel
⑹ Control of the whole line clock system
⑺ The working state of the power supply
⑻ Basic troubleshooting principles, etc
The monitoring terminal can also print and record the fault status and time . When the system fails, it can send out sound and light alarm , Indicate the fault location . meanwhile , Fault information can be transmitted to the centralized alarm terminal of customer service information platform , In order to manage with customer service information system （ Through the network card to achieve ）. in addition , It can also realize remote network alarm , Timely transfer the relevant information to the communication tools of the equipment management personnel who are not at the fault site .
NTP Server function
Network time protocol （Network Time Protocol） Is a synchronous time protocol that serves computer clocks over the Internet . It provides a synchronous time mechanism , It can adjust the time allocation with the speed of light in the large and complex Internet . It uses a returnable time design , Its characteristics are ： The time server is a distributed subnet , Can self organize and operate 、 Hierarchical management configuration , After wired or wireless synchronization, the logic clock reaches the national standard time . Besides , Through the local routing algorithm and time background program , The server can reallocate the standard time .
NTP Design has brought three products — Clock offset 、 Time delay and difference , All three are associated with the specified reference clock . Clock offset represents the number of offsets caused by adjusting the local clock to match the reference clock ; Time delay represents the delay time between sending a message within a specified time and the reference clock ; The difference represents the maximum offset error of the local clock relative to the reference clock . Because most host time servers are synchronized through other peer time servers , So each of these three products has two components ： One is the part determined by reciprocity , This part is relative to the reference source of the original standard time ; The second is the part measured by the host , This part is relative to equivalence . Each part is independently maintained in the agreement , This makes it easy to control errors and manage the subnet itself . They not only provide precise measurements of offset and delay , And it provides a clear maximum error range , This way, the user interface can not only determine the time , And it can determine the accuracy of the time .
Adopt industrial standards ,19 Inch standard rack type , By receiving the satellite's standard time signal , Synchronize your internal clock first , And then through 10M/100M The Ethernet card synchronizes the computer equipment in the LAN , The specific hardware configuration is as follows ：
1、 Input signal ： Time code Time code：BNC or DB9
2、 The output signal ：10BaseT/100BaseT Ethernet interface /RJ45 be used for NTP
Time code Time code：BNC or DB9
3、 Management port ：10BaseT/100BaseT Ethernet interface /RJ45 Used to manage
RS-232： The terminal interface is used to configure
4、 Network time synchronization accuracy ：TCP/IP On the network NTP-1-10ms
5、 Environmental requirements ： working temperature ：0～＋50℃;
6、 Power supply ： Alternating current (ac) 220V±25%,50Hz±5%;
7、 Power frequency ：50Hz±5%.
8、 power ：≤15W
9、 Mean time between failures （MFBF）：≥7 Thousands of hours
184.108.40.206. Equipment configuration and performance index
Equipment performance index ：
Network master clock
* Power supply ： Alternating current (ac) 220V±15%,50Hz±5%
* Synchronization accuracy ： Normal reception GPS/ Beidou / When the upper network signals , With the upper network /GPS/ The time error of Beidou signal does not exceed ≤±1 Microsecond
* Can take ≤120 Taiwan Level 2 master clock , It can be equipped with pointer and digital slave clock 4200 Noodles
* Synchronization error with slave clock ≤10ms
*NTP The server ≤2ms,BITS The server ≤2ns
* Scalable NTP Server function
* Free running accuracy is better than ：
ⅰ. After an hour of operation , The accuracy is 99.998%
ⅱ. After a week of operation , The accuracy is 99.9997%
*GPS/ When the Beidou signal is restored, the completion time will be automatically calibrated ：5 second
* The precision of the crystal oscillator itself ：1×10－8 second / God
* Output interface ： standard RS422 Interface /NTP Interface
* Clock load mode ： Point to many
* transmission distance ： Standard communication distance of network cable
* Power waste ： Less than 10W
* ambient temperature : -10℃～+65℃
* Relative humidity : 5％～95％
GPS/ Beidou receiving device
* Tracking satellites ：≥6 Satellites tracking at the same time
* Timing accuracy ：0.1 second / year
* The interface way ： standard RS-422 Interface
* Antenna feeder length ：30 rice
* The antenna ： With lightning protection device , waterproof 、 Anticorrosive , The protection level is not lower than IP65
* Signal transmission distance ：100 rice
* Power supply ：AC220V±20%,50Hz±5%
Single side digital slave clock
* Display minutes and seconds 、 Specific date 、 The week is optional .
* Support synchronous public 、 The private network NTP Time server .
* Support countdown display time .
* Remote software can turn off the clock display , Reduce energy consumption .
* The brightness of each display module is adjustable , Make sure the layout is displayed LED The brightness is even .
* The clock switches the master automatically 、 To prepare NTP Time server address .
* Clock software can be updated online .
* Digital tube pen failure automatic scanning alarm .
* Support networked batch management
* Timing accuracy ：0.5 second / God
* Working power supply ：AC 220V 50Hz
* working temperature ：-20~70℃
* Dimensions ：70*30*5cm;70*19*5cm;
*LED Display unit luminous intensity ：≥200cd/㎡
* Contrast ：≥10：1
*LED The visual angle of the screen ：≥±65º
*LED display MTBF：≥50000 Hours
* Independent timing accuracy ：≤±0.5 second / God
* Environmental requirements ： working temperature -40～＋50℃
NTP Network time server
* Input signal ： Time code Time code：BNC or DB9
* The output signal ：10BaseT/100BaseT Ethernet interface /RJ45 be used for NTP
Time code Time code：BNC or DB9
* Management port ：10BaseT/100BaseT Ethernet interface /RJ45 Used to manage
RS-232： The terminal interface is used to configure
* Network time synchronization accuracy ：TCP/IP On the network NTP：1-10ms
* Environmental requirements ： working temperature ：0～＋50℃;
* Power supply ： Alternating current (ac) 220V±25%,50Hz±5%;
* Power frequency ：50Hz±5%.
* power ：≤15W
* Mean time between failures （MFBF）：≥7 Thousands of hours
Detailed description of equipment configuration
In each network communication control room （ Computer room ） Set up one NTP The clock server is in the cabinet , In the halls of other departments 、 corridor 、 The display screen of slave clock is set in eye-catching places such as passageway and inpatient house ;NTP The clock server device includes NTP Ethernet output interface 、GPS/ Beidou signal receiving processor and network interface signal for synchronization of slave clock display screen .
The detailed description is as follows ：
The product name
Brand and model
GPS Network master clock
use GPS Satellites as clock sources , Output 4 road NTP Network interface (RJ45) For computer network clock synchronization ,2 road RS232 Serial port , The accuracy is up to 1-10ms, Dual power redundancy backup , Rack design ,30 Meter antenna , Client software , Antenna bracket and other accessories ;
Network clock screen
5 Inch digital tube \ Power module \ Display minutes and seconds \ Network module
Network clock screen
2.3 and 5 Inch digital tube \ Power module \ Show day, month, week, hour, minute, second \ Network module