JP2008151556A - Method for correcting time in remote monitoring/controlling system - Google Patents

Method for correcting time in remote monitoring/controlling system Download PDF

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JP2008151556A
JP2008151556A JP2006337896A JP2006337896A JP2008151556A JP 2008151556 A JP2008151556 A JP 2008151556A JP 2006337896 A JP2006337896 A JP 2006337896A JP 2006337896 A JP2006337896 A JP 2006337896A JP 2008151556 A JP2008151556 A JP 2008151556A
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correction
time
computer
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error
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Takanori Mochizuki
孝紀 望月
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Meidensha Corp
Meidensha Electric Manufacturing Co Ltd
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Meidensha Electric Manufacturing Co Ltd
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Abstract

<P>PROBLEM TO BE SOLVED: To eliminate the need for an external clock and a communication means with Internet when a time is synchronized between a master station and a slave station. <P>SOLUTION: When the first correction time is inputted, the current time in a computer is stored as the first correction time (S2). A period n<SB>a</SB>required for generating an error of 1 sec in the computer is obtained from a time difference t between the first correction time and the second correction time, and an error ±s of the current time in the computer (S4). A process for correcting a clock in the computer by ±1 sec at the correction period n<SB>a</SB>is repeated (S6, S8). At the third correction time, a correction period z<SB>a</SB>is obtained by adjusting the correction value at the correction period n<SB>a</SB>in the second correction by the period n<SB>a</SB>required for generating the error of 1 sec in the computer. A process for correcting the clock in the computer is repeated at each correction period z<SB>a</SB>(S7). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

本発明は、遠方監視制御システムの時刻補正方法に関する。   The present invention relates to a time correction method for a remote monitoring control system.

遠方監視制御システムは、電力系統や水処理プラントなど、広域に分散される機器・設備の状態を各子局で監視情報(オン/オフ信号、計測情報)として収集して中央の親局に伝送し、親局では受信した多くの監視情報さらにはオペレータの操作信号を基にして生成した制御情報を各子局側に伝送し、各子局では制御情報に従って機器・設備を制御する。これら監視制御に必要な信号処理の大部分は制御用コンピュータによってディジタル的に処理される。   The remote monitoring and control system collects the status of equipment and facilities distributed over a wide area, such as power systems and water treatment plants, as monitoring information (on / off signal, measurement information) at each slave station and transmits it to the central master station Then, the master station transmits a lot of received monitoring information and control information generated based on the operation signal of the operator to each slave station, and each slave station controls equipment and facilities according to the control information. Most of the signal processing necessary for the supervisory control is digitally processed by a control computer.

ここで、各子局が収集する監視情報に時刻情報を付加して親局側に伝送する場合がある。例えば、配電系統の各区分所の負荷状況を各子局が収集して中央の管理室に伝送し、管理室ではこれらの集計などを日報として管理する場合がある。この場合、各子局では単位時間毎に負荷電力を集計し、これに時刻情報を付加して親局側に伝送する。各子局及び親局は時刻情報を基に負荷情報を集計及び管理するため、それぞれに内部時計、つまりハードウェアクロック(水晶発振器)を設けているが、この内部時計に遅れや進みがあると、正確な負荷状況の管理ができない。   Here, time information may be added to the monitoring information collected by each slave station and transmitted to the master station. For example, there are cases where each slave station collects the load status of each division in the distribution system and transmits it to a central management room, and the management room manages these summaries as daily reports. In this case, each slave station aggregates the load power every unit time, adds time information to this, and transmits it to the master station side. Each slave station and master station has an internal clock, that is, a hardware clock (crystal oscillator), for counting and managing load information based on time information. , Accurate load status management is not possible.

そこで、この種の監視制御システムでは、各子局と親局間に時刻同期装置を設け、各子局の監視信号に時刻同期を得た監視を可能にしている。この時刻同期装置は、各子局および親局のコンピュータがもつ内部時計に発生する時刻の狂い(例えば、1日当たり5秒程度)を、外部時計(FM、電波時計、GPS時刻情報)によって補正、またはインターネット上のNTPサービスのアクセスによって補正するようにしている(例えば、特許文献1参照)。
特開平7−284181号公報
In view of this, in this type of supervisory control system, a time synchronization device is provided between each slave station and the master station to enable monitoring with time synchronization obtained from the monitor signal of each slave station. This time synchronizer corrects a time lag (for example, about 5 seconds per day) generated in an internal clock of each slave station and a master station computer by an external clock (FM, radio clock, GPS time information), Alternatively, correction is performed by accessing an NTP service on the Internet (see, for example, Patent Document 1).
JP-A-7-284181

従来の外部時計による時刻補正方式では、その受信機設置と時計信号処理デバイスなどのハードウェア費用とアンテナ設置工事が必要となる。   The conventional time correction method using an external clock requires installation of the receiver, hardware costs such as a clock signal processing device, and antenna installation work.

一方、インターネット上のNTPサービスを利用する場合には、プロバイダとの毎月の契約費用およびウイルス対策が必要となる。   On the other hand, when using an NTP service on the Internet, monthly contract costs with a provider and virus measures are required.

本発明の目的は、上記の外部時計やインターネットとの通信手段を不要にして内部時計の時刻補正ができる時刻補正方法を提供することにある。   An object of the present invention is to provide a time correction method capable of correcting the time of an internal clock without using the above-described external clock and communication means with the Internet.

本発明は、前記の課題を解決するため、任意のタイミングで補正時刻が入力されたとき、該補正時刻とコンピュータの内部時計の現在時刻との正負誤差分から、コンピュータに単位時間の誤差が発生するのに要した期間を求め、この期間を補正期間としてコンピュータの内部時計を単位時間ずつ補正し、この補正に際して前回の補正により生じたコンピュータの内部時計の誤差分を考慮した補正期間で補正するようにしたもので、以下の方法を特徴とする。   In order to solve the above-described problems, the present invention generates a unit time error in a computer from a positive / negative error between the correction time and the current time of the internal clock of the computer when the correction time is input at an arbitrary timing. The computer internal clock is corrected for each unit time using this period as a correction period, and the correction is performed in a correction period that takes into account the error of the computer internal clock caused by the previous correction. It features the following method.

(1)遠方監視制御システムの各子局および親局がもつコンピュータの内部時計の時刻補正方法であって、
前記コンピュータは、任意のタイミングで補正時刻が入力されたとき、該補正時刻とコンピュータの内部時計の現在時刻との正負誤差分から、コンピュータに単位時間の誤差が発生するのに要した期間を求め、この期間を補正期間としてコンピュータの内部時計を単位時間ずつ補正し、この補正に際して前回の補正により生じたコンピュータの内部時計の誤差分を調節した補正期間で補正する処理手順を有することを特徴とする。
(1) A time correction method for an internal clock of a computer possessed by each slave station and master station of a remote monitoring control system,
When the correction time is input at an arbitrary timing, the computer obtains the period required for the unit time error to occur in the computer from the correction error between the correction time and the current time of the internal clock of the computer, It is characterized by having a processing procedure for correcting the internal clock of the computer unit time by using this period as a correction period, and correcting the error by the correction period adjusted for the error of the internal clock of the computer caused by the previous correction. .

以上のとおり、本発明によれば、コンピュータがもつデータ処理機能を利用して、前回に時刻補正した補正を基に、内部時計を自己補正するようにしたため、従来の補正方法で必要な外部時計やインターネットとの通信手段を不要にして時刻補正ができる。   As described above, according to the present invention, the internal clock is self-corrected based on the previous time correction using the data processing function of the computer, so that the external clock necessary for the conventional correction method is used. And the time can be corrected without using communication means with the Internet.

しかも、補正に際して前回の補正により生じたコンピュータの内部時計の誤差分を調節した補正期間で補正するため、補正精度を高めた各子局と親局間の時刻同期が可能となる。   In addition, since correction is performed in a correction period in which the error of the internal clock of the computer caused by the previous correction is adjusted, time synchronization between each slave station and the master station with improved correction accuracy becomes possible.

図1は、本発明の実施形態を示す時刻補正処理フローであり、時刻同期を必要とする遠方監視制御システムにおける各子局および親局が搭載するコンピュータの時刻同期ソフトウェア構成として実現される。   FIG. 1 is a time correction processing flow showing an embodiment of the present invention, which is realized as a time synchronization software configuration of a computer installed in each slave station and parent station in a remote monitoring control system that requires time synchronization.

本実施形態では、任意のタイミングで補正時刻が入力されたとき、コンピュータの内部時計が刻む現在時刻(PC時刻)を1回目の補正時刻として記憶しておき、この補正時刻から2回目の補正時刻までの時間差(t)とコンピュータの現在時刻(PC時刻)がもつ正負誤差分(±s)とから、コンピュータに1秒の誤差が発生するのに要した期間(na)を求め、この補正期間(na)毎にコンピュータの内部時計を正負1秒ずつ補正する処理を繰り返してゆき、3回目の補正時刻では2回目の補正における補正期間(na)での補正値(正負1秒)に、コンピュータに1秒の誤差が発生するのに要した期間(na)を調整した補正期間(za)を求め、この補正期間(za)毎にコンピュータの内部時計を正負1秒ずつ補正する処理を繰り返し、4回目以降の補正時刻では、3回目の補正と同じに過去に調整した補正を基に時刻補正を繰り返す。 In this embodiment, when the correction time is input at an arbitrary timing, the current time (PC time) recorded by the internal clock of the computer is stored as the first correction time, and the second correction time from this correction time. The period (n a ) required for the computer to generate an error of 1 second is obtained from the time difference (t) up to and the positive / negative error (± s) of the current computer time (PC time), and this correction is performed. The process of correcting the internal clock of the computer by 1 second for each period (n a ) is repeated, and the correction value (positive / negative 1 second) in the correction period (n a ) in the second correction time at the third correction time. Then, a correction period (z a ) obtained by adjusting a period (n a ) required for generating an error of 1 second in the computer is obtained, and the internal clock of the computer is incremented by 1 second for each correction period (z a ). Repeat the correction process. Returns, in the fourth and subsequent correction time, repeat the time correction based on the third correction and the same correction has been adjusted in the past.

図2は、図1の補正方法による時刻補正の具体例を示し、以下、図1と図2を参照してコンピュータの時刻補正動作を処理手順(S1)〜(S10)に分けて説明する。   FIG. 2 shows a specific example of time correction by the correction method of FIG. 1, and the time correction operation of the computer will be described below by dividing it into processing procedures (S1) to (S10) with reference to FIG. 1 and FIG.

(S1)任意のタイミングで1回目の補正時刻(現在時刻)を入力する。この補正時刻は、例えば、保守員が予め数値(年月日、時分秒)を設定しておき、テレビやラジオから発信される時報に合わせて入力操作する。または、保守員が電波時計などの受信機能をもつ時計を携帯している場合はその時刻を利用することでもよい。   (S1) The first correction time (current time) is input at an arbitrary timing. For example, maintenance personnel set numerical values (year / month / day, hour / minute / second) in advance and perform an input operation in accordance with a time signal transmitted from a television or radio. Alternatively, when a maintenance person carries a clock having a reception function such as a radio clock, the time may be used.

(S2)上記の(S1)では1回目の補正時刻入力になり、この補正時刻とコンピュータの現在時刻との誤差(±s)を算出し、補正時刻はコンピュータ時刻に補正後、今回補正時刻としてメモリ等に格納しておく。   (S2) In the above (S1), the first correction time is input, and an error (± s) between this correction time and the current computer time is calculated. Store in memory.

図2の例では、1回目の補正時刻「2005年1月8日、10時0分0秒」が入力され、このときのコンピュータ時刻が「2005年1月8日、10時3分0秒」とすると、誤差は「−3分」となる。また、今回補正時刻は「2005年1月8日、10時3分0秒」とする。   In the example of FIG. 2, the first correction time “January 8, 2005, 10:00:00” is input, and the computer time at this time is “January 8, 2005, 10:30:30”. ", The error is" -3 minutes ". The correction time this time is “January 8, 2005, 10: 3: 0”.

(S3)前回補正入力ありか否かをチェックする。この段階では、1回目の補正時刻入力のため、前回の補正入力なし(N)となり、以下の(S9)にジャンプし、今回補正時刻を前回補正時刻にセットし、続いて(S10)により次の時刻補正入力を待つ。   (S3) It is checked whether or not there is a previous correction input. At this stage, since the first correction time is input, the previous correction input is not performed (N), the process jumps to (S9) below, the current correction time is set to the previous correction time, and then the next correction is performed by (S10). Wait for the time correction input.

図2の例では、「2005年1月8日、10時3分0秒」が前回補正時刻として、補正周期の演算に供される。   In the example of FIG. 2, “January 8, 2005, 10: 3: 0” is used as the previous correction time for the calculation of the correction cycle.

(S4)2回目の補正時刻入力がなされたとき(S1)、上記の(S2)によって誤差(±s)の算出と、コンピュータ時刻を今回補正時刻として格納し、(S3)では前回補正入力あり(Y)になる。   (S4) When the second correction time is input (S1), the calculation of the error (± s) and the computer time are stored as the current correction time in (S2), and the previous correction input is present in (S3). (Y).

このとき、補正周期の演算は、前回補正時刻と今回補正時刻との時間差(t)と誤差(±s)より、1秒の誤差が生じるに要した期間(na)を補正期間として求める。すなわち、na=|t÷s|の演算を行う。また、誤差(±s)が負であれば補正値(nh)は「−1秒」、正であれば「+1秒」とする。 At this time, in the calculation of the correction cycle, a period (n a ) required for generating an error of 1 second is obtained as a correction period from the time difference (t) between the previous correction time and the current correction time and the error (± s). That is, the calculation of n a = | t ÷ s | is performed. If the error (± s) is negative, the correction value (n h ) is “−1 second”, and if it is positive, it is “+1 second”.

図2の例では、2回目の補正時刻が「2005年2月8日、10時10分10秒」に入力され、このときのコンピュータ時刻が「2005年2月8日、10時8分0秒」とすると、誤差(±s)は「+130秒」、1回目と2回目の補正時刻の時間差(t)は「2678880秒」となり、期間(na)は「20606秒」、補正値(nh)は「+1秒」となる。また、今回の補正時刻は「2005年2月8日、10時8分0秒」となる。 In the example of FIG. 2, the second correction time is input at “February 8, 2005, 10:10:10”, and the computer time at this time is “February 8, 2005, 10: 08: 0”. Assuming “second”, the error (± s) is “+130 seconds”, the time difference (t) between the first and second correction times is “2678880 seconds”, the period (n a ) is “20606 seconds”, and the correction value ( n h ) is “+1 second”. In addition, the correction time this time is “February 8, 2005, 10: 8: 0”.

(S5)前々回補正入力があるか否かをチェックする。この段階では、2回目の補正時刻入力のため、前々回の補正入力なし(N)となり、以下の(S6)にジャンプする。   (S5) It is checked whether or not there is a correction input last time. At this stage, since the correction time is input for the second time, there is no correction input two times before (N), and the process jumps to (S6) below.

(S6)今回算出した補正期間(na)を補正周期(za)とし、補正値(nh)を補正値(zh)として(S8)にジャンプし、(S8)では補正周期(za)毎に補正値(zh)=±1秒の時刻補正をする。 (S6) The correction period (n a ) calculated this time is set as the correction period (z a ), the correction value (n h ) is set as the correction value (z h ), and the process jumps to (S8). In (S8), the correction period (z a ) Correction time (z h ) = ± 1 second is corrected every time.

図2の例では2回目の補正時刻入力で求めた補正期間(na)=「20606秒」毎に、補正値(nh)=「+1秒」でコンピュータの時計時刻を補正し、コンピュータの内部時計の遅れを進めていく。 In the example of FIG. 2, the computer clock time is corrected with the correction value (n h ) = “+ 1 second” every correction period (n a ) = “20606 seconds” obtained by the second correction time input. Advance the delay of the internal clock.

(S7)3回目の補正時刻が入力された場合、(S2)、(S4)の処理が実行され、3回目での誤差(±s)および補正期間(na)が求められる。さらに、(S5)では前々回補正入力ありになる。この段階では、(S6)で置換された現在の補正周期(za)での補正値(zh)に、今回求められた補正期間(na)を以下の演算により調節する。 (S7) When the third correction time is input, the processes of (S2) and (S4) are executed, and the error (± s) and correction period (n a ) at the third time are obtained. Further, in (S5), there is a correction input two times before. At this stage, the correction period (n a ) obtained this time is adjusted to the correction value (z h ) in the current correction cycle (z a ) replaced in (S6) by the following calculation.

w=|na÷za|×zh+nh、za=na÷w
この調節は、前回と今回の補正期間の比率|na÷za|に2回目の補正値(zh)を乗じたもので今回の補正値(nh)を調節した誤差分(w)を求め、この誤差分(w)で今回の補正期間(na)を除したものを補正期間(za)とし、誤差分(w)が負であれば補正値(zh)は−1秒、正であれば+1秒とする。
w = | n a ÷ z a | × z h + n h , za = n a ÷ w
This adjustment is the ratio of the previous and current correction period | n a ÷ z a | error amount adjusted to the second correction value (z h) the current in multiplied by the correction value (n h) (w) The correction period (z a ) is obtained by dividing the current correction period (n a ) by this error (w), and if the error (w) is negative, the correction value (z h ) is −1. Second, if positive, +1 second.

図2の例では、3回目の補正時刻入力が「2005年3月3日、12時12分30秒」で、このときのコンピュータ時刻が「2005年3月3日、12時12分40秒」の場合、前回の補正時刻との時間差(t)=「1994550秒」で誤差(±s)=−10秒のため、「199455秒」周期で1秒進んだことになる。この周期で1秒戻しが必要になる前回の補正では「199455秒」周期当たり「9.68秒」の進み補正を行っているので、これを考慮すると今回では「8.68秒」の進みとすればよい。つまり、2回目と3回目の補正を考慮し、「22978秒」周期で1秒の進み補正をする。   In the example of FIG. 2, the third correction time input is “March 3, 2005, 12:12:30”, and the computer time at this time is “March 3, 2005, 12:12:40”. In the case of “,” the time difference (t) from the previous correction time = “1994550 seconds” and the error (± s) = − 10 seconds, so that the period of “1994455 seconds” is advanced by 1 second. In the previous correction that requires a 1 second return in this cycle, the advance correction of “9.68 seconds” per “1994455 seconds” cycle is performed. do it. In other words, taking the second and third corrections into consideration, the lead correction is performed for 1 second with a period of “22978 seconds”.

(S8)上記の(S6)または(S7)で求めた補正周期(za)毎に補正値(zh)でコンピュータの内部時計を時刻補正する。この補正は、図3に示す処理フローで実現され、補正周期(za)に時限設定されたタイマがタイムアップしたとき(S11)、補正値(zh)の正負をチェックし(S12)、負であればコンピュータの内部時計を1秒進め(S13)、正であればV1秒遅らせ(S14)、タイマの次回のタイムアップを待つ(S15)。 (S8) The time of the internal clock of the computer is corrected with the correction value (z h ) at every correction cycle (z a ) obtained in (S6) or (S7) above. This correction is realized by the processing flow shown in FIG. 3, and when the timer set for the time limit in the correction cycle (z a ) times out (S11), the correction value (z h ) is checked for positive / negative (S12), If it is negative, the internal clock of the computer is advanced by 1 second (S13). If it is positive, it is delayed by V1 seconds (S14), and the next time-up of the timer is awaited (S15).

(S9)補正時刻入力がなされたときに、今回補正時刻を前回補正時刻としてセットしておく。   (S9) When the correction time is input, the current correction time is set as the previous correction time.

(S10)次の時刻補正入力を待つ。   (S10) Wait for the next time correction input.

以上までに説明した本実施形態において、補正周期毎に±1秒の補正をする場合を示すが、システム構成に応じて±0.5秒など他の単位時間に適宜変更することができる。   In the present embodiment described above, a case where correction is performed for ± 1 second every correction cycle is shown, but it can be appropriately changed to other unit time such as ± 0.5 second depending on the system configuration.

本発明の実施形態を示す時刻補正処理フロー。The time correction processing flow which shows embodiment of this invention. 実施形態の補正方法による時刻補正の具体例。A specific example of time correction by the correction method of the embodiment. 実施形態におけるコンピュータの内部時計の時刻補正処理フロー。The time correction processing flow of the internal clock of the computer in the embodiment.

Claims (1)

遠方監視制御システムの各子局および親局がもつコンピュータの内部時計の時刻補正方法であって、
前記コンピュータは、任意のタイミングで補正時刻が入力されたとき、該補正時刻とコンピュータの内部時計の現在時刻との正負誤差分から、コンピュータに単位時間の誤差が発生するのに要した期間を求め、この期間を補正期間としてコンピュータの内部時計を単位時間ずつ補正し、この補正に際して前回の補正により生じたコンピュータの内部時計の誤差分を調節した補正期間で補正する処理手順を有することを特徴とする遠方監視制御システムの時刻補正方法。
A time correction method for an internal clock of a computer possessed by each slave station and master station of a remote monitoring control system,
When the correction time is input at an arbitrary timing, the computer obtains the period required for the unit time error to occur in the computer from the correction error between the correction time and the current time of the internal clock of the computer, It is characterized by having a processing procedure for correcting the internal clock of the computer unit time by using this period as a correction period, and correcting the error by the correction period adjusted for the error of the internal clock of the computer caused by the previous correction. Time correction method for remote monitoring control system.
JP2006337896A 2006-12-15 2006-12-15 Method for correcting time in remote monitoring/controlling system Pending JP2008151556A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2015014536A (en) * 2013-07-05 2015-01-22 三菱電機株式会社 Client device

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2015014536A (en) * 2013-07-05 2015-01-22 三菱電機株式会社 Client device

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