JPS63290978A - Diagnostic device for two-out-of-four circuit - Google Patents

Diagnostic device for two-out-of-four circuit

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Publication number
JPS63290978A
JPS63290978A JP62125901A JP12590187A JPS63290978A JP S63290978 A JPS63290978 A JP S63290978A JP 62125901 A JP62125901 A JP 62125901A JP 12590187 A JP12590187 A JP 12590187A JP S63290978 A JPS63290978 A JP S63290978A
Authority
JP
Japan
Prior art keywords
opening
closing means
circuit
signal
contacts
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.)
Pending
Application number
JP62125901A
Other languages
Japanese (ja)
Inventor
Setsuo Arita
節男 有田
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.)
Hitachi Ltd
Original Assignee
Hitachi 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 Hitachi Ltd filed Critical Hitachi Ltd
Priority to JP62125901A priority Critical patent/JPS63290978A/en
Publication of JPS63290978A publication Critical patent/JPS63290978A/en
Pending legal-status Critical Current

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  • Safety Devices In Control Systems (AREA)

Abstract

PURPOSE:To evaluate the soundness of contacts constituting a two-out-of-four circuit by providing a current detecting means to the two-out-of-four circuit, applying a test signal to the contacts successively, and deciding the output result of the current detecting means. CONSTITUTION:Signal processors 17-20 input and process signals from sensors A1-N1, A2-N2, A3-N3, and A4-N4 which are made redundant and output driving signals (a)-(d) for scramming a plant to an output circuit 16 when processing results exceed a prescribed value. A diagnostic device 25 assigns the signals (a)-(d) to specific logic, outputs the test signal 26 to switches 21-24, and evaluates the soundness of contacts 2-9 with a current detection result signal 27 as the output result of the current detecting means at this time.

Description

【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、冗長化装置に係り、特に、冗長化装置の出力
信号、あるいは、入力信号の多数決を組む2アウトオブ
4回路の健全性を評価する診断装置に関する。
[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a redundancy device, and in particular, to the soundness of a 2-out-of-4 circuit that makes a majority decision on output signals or input signals of the redundancy device. The present invention relates to a diagnostic device for evaluation.

〔従来の技術〕[Conventional technology]

高信頼化が要求される制御系では、制御装置を冗長化す
る方法が採用される。このような冗長化システムでは、
例えば、保守のために一つの制御装置をとりはずしても
制御システムとしては多数決が組めるようになっている
ことが要求される場合がある。例えば、原子カブラン1
〜における安全保護システムはその代表例であり、シス
テムとして2アウトオブ4論理が構成される。これは一
つの保護装置をとりはずしても2アウトオブ3論理と組
んで常に多数決が組めるようにしている。例えば、原子
カバン1〜ブツク、昭和51年、p263p267には
各保護装置からの出力を選択する各種の多数決回路の構
成方法が述べられている。これらの方法のうち2アウト
オブ4回路は具体的には第2図に示すように構成してい
る。これは、接点2〜9によってスクラム弁11の励磁
コイル10に印加する交流電圧を制御する2アウトオブ
4回路である。信号a −dは開閉手段である接点2〜
9を制御するための駆動信号であり、通常は、接点2〜
9が閉状態となるように論理″1′″ (信号ありの状
態)なる信号を出力している。原子炉をスクラムすると
きには駆動信号を論理“017(信号なしの状態)なる
信号を出力して各接点を開放状態にする。このような論
理としているのは安全側動作(例えば信号ケーブルが切
れてもスクラムできる)を優先させているからである。
In control systems that require high reliability, a method of making control devices redundant is adopted. In such a redundant system,
For example, even if one control device is removed for maintenance, the control system may be required to be able to perform majority voting. For example, atomic kabulan 1
The safety protection system in ~ is a typical example, and the system is configured with 2 out of 4 logic. This combines with the 2-out-of-3 logic to ensure that even if one protection device is removed, there is always a majority vote. For example, Atomic Bag 1-Book, 1976, p263, p267 describes how to configure various majority circuits for selecting outputs from each protection device. Among these methods, the 2-out-of-4 circuit is specifically constructed as shown in FIG. This is a 2-out-of-4 circuit that controls the AC voltage applied to the excitation coil 10 of the scram valve 11 by contacts 2-9. Signals a to d are contacts 2 to 2, which are opening/closing means.
This is a drive signal for controlling contacts 9, and is normally used for controlling contacts 2 to 9.
9 is in a closed state, a signal of logic "1" (signal present state) is output. When scramming the reactor, the drive signal outputs a logic "017 (no signal state)" signal to open each contact.This logic is used to ensure safe operation (for example, if the signal cable is cut). This is because Scrum can also be used) as a priority.

なお、端子1には常時交流電圧が印加されている。Note that an alternating current voltage is constantly applied to the terminal 1.

〔発明が解決しようとする問題点〕[Problem that the invention seeks to solve]

システム全体の高信頼化を達成するには、第2図に示し
た2アウトオブ4回路が動作すべきときに動作するか否
か、つまり、健全であるか否かを判定できるようにする
ことが要求される。しかし、2アウトオブ4回路を構成
する接点の、健全性を評価する手段がなかった。
In order to achieve high reliability of the entire system, it is necessary to be able to determine whether or not the 2-out-of-4 circuit shown in Figure 2 operates when it should, that is, whether it is healthy or not. is required. However, there was no means to evaluate the soundness of the contacts that make up the 2-out-of-4 circuit.

本発明の目的は、オンラインで、2アウトオブ4回路を
構成する接点の、健全性を評価できる診断装置を提供す
ることにある。
An object of the present invention is to provide a diagnostic device that can evaluate the health of contacts forming a 2-out-of-4 circuit online.

〔問題点を解決するための手段〕[Means for solving problems]

上記目的は、2アウトオブ4回路において並列回路を構
成する部分に電流検出手段を設け、2アウトオブ4回路
を構成する接点にテスト信号を順次印加し、電流検出手
段の出力結果を判定することによって達成できる。
The above purpose is to provide a current detection means in a part that constitutes a parallel circuit in a 2-out-of-4 circuit, sequentially apply a test signal to the contacts that constitute the 2-out-of-4 circuit, and judge the output result of the current detection means. This can be achieved by

〔作用〕[Effect]

以上のようにして2アウトオブ4回路を診断することに
よって2アウトオブ4回路の接点の健全性をオンライン
で判断できる。
By diagnosing the 2 out of 4 circuit as described above, the health of the contacts in the 2 out of 4 circuit can be determined online.

〔実施例〕〔Example〕

第1図は、本実施例の回路構成であり、第2図の2アウ
トオブ4回路をオンラインで診断するための回路構成図
である。図においては、一つの信号処理装置、一つのス
イッチ(例えば、信号処理装置17.スイッチ21−)
から成る信号処理系統を四系統もっている。信号処理装
置17はセンサA1〜N1に、信号処理装置18はセン
サA2〜N2に、信号処理装置19はセンサA3〜N8
に、信号処理装置20はセンサA4〜N4に接続されて
いる。
FIG. 1 shows the circuit configuration of this embodiment, and is a circuit configuration diagram for diagnosing the 2-out-of-4 circuit shown in FIG. 2 online. In the figure, one signal processing device and one switch (for example, signal processing device 17, switch 21-)
It has four signal processing systems consisting of: The signal processing device 17 is connected to the sensors A1 to N1, the signal processing device 18 is connected to the sensors A2 to N2, and the signal processing device 19 is connected to the sensors A3 to N8.
In addition, the signal processing device 20 is connected to the sensors A4 to N4.

ここで同じアルファベットで示した四つのセンサ(例え
ば、A、 1 、 A 21 A a 、 A a )
は近接して配置されており、原子カプラントの同じ状態
量を測定する。本実施例では一つの状態量に対して」二
連のように四つのセンサを設けたが、一つのセンサを設
けてこのセンサの出力信号を信号処理装置17〜20に
それぞれ入力してもよい。信号処理装置17〜20は冗
長化したセンサA1〜N1.AX〜NZ、、A8〜N8
、及びA4−N4から出力された信号をそれぞれ取込ん
で演算処理を行い、その処理結果が規定値を越える場合
にはプラントをスクラムさせるための駆動信号a −d
を出力回路16に出力する。出力回路16は、前述のよ
うに、四つの信号a −dの多数決(2アウトオブ4)
をとってスクラム弁11を制御する。この出力回路16
には、接点に流れる電流を検出するための電流検出手段
30〜35を設けている。この電流検出手段は1例えば
、変圧器などによって実現できる。
Four sensors indicated here with the same alphabet (e.g. A, 1, A21 Aa, Aa)
are placed in close proximity and measure the same state quantity of the atomic couplant. In this embodiment, four sensors are provided in two series for one state quantity, but it is also possible to provide one sensor and input the output signal of this sensor to each of the signal processing devices 17 to 20. . The signal processing devices 17-20 include redundant sensors A1-N1. AX~NZ,,A8~N8
, and the signals output from A4-N4, respectively, and perform arithmetic processing, and if the processing result exceeds a specified value, drive signals a - d are used to scram the plant.
is output to the output circuit 16. As mentioned above, the output circuit 16 is a majority decision (2 out of 4) of the four signals a to d.
to control the scram valve 11. This output circuit 16
are provided with current detection means 30 to 35 for detecting the current flowing through the contacts. This current detection means can be realized by, for example, a transformer.

接点2〜9から成る2アウトオブ4回路に電流検出手段
を直接接続したくない場合には、例えば、オシロスコー
プのカレントプローブ等に用いられている電流変成器を
利用すればよい。
If it is not desired to directly connect the current detection means to the 2-out-of-4 circuit consisting of contacts 2 to 9, a current transformer used in, for example, a current probe of an oscilloscope may be used.

診断装置25は、信号a −dを表1に示す論理にすべ
て、テスト信号26をスイッチ21〜24に出力し、こ
のときの電流検出手段の出力結果である電流検出結果信
号27で接点2〜9の健全性を評価する。具体的には表
1に示すパターンで各接点の健全性を判断する。
The diagnostic device 25 outputs all the signals a to d according to the logic shown in Table 1, the test signal 26 to the switches 21 to 24, and the current detection result signal 27, which is the output result of the current detection means at this time, to the contacts 2 to 2. Evaluate the soundness of 9. Specifically, the health of each contact is determined based on the pattern shown in Table 1.

診断装置25は、まず、駆動信号a −dをすべて論理
“1″ (全接点を閉の状態にする)にするテスト信号
を出力する。このとき、各接点は閉状態になるから、す
べての電流検出手段30〜35は、これら接点に電流が
流れていること(電流検出手段の出力は論理LL I 
II )を検出する。ところが、電流検出手段の出力が
すべて論理rr I IIにならなければ、各接点のい
ずれかが開状態に縮退故障していることがわかる。例え
ば、電流検出手段30.31,33..34のうちいず
れかの出力のみが論理“O”であれば、それに対応する
接点が開状態になっていると判断できる。また、電流検
出手段32の出力のみが論理II OIIであれば接点
4、あるいは5が開状態になっていると判断でき、電流
検出手段35の出力のみが論理II OIIであれば接
点8あるいは9が開状態になっていると判断できる。し
かし、全電流検出手段の出力がすべて論理II OF+
である場合には、全接点2〜9が開状態になっているの
ではなく、信号処理装置17〜20からスクラム弁11
を動作すべく信号が出力されていると判定する。なぜな
らば、接点2〜9すへてが同時に開状態に縮退故障する
ことは確率的に極めて低いからである。
The diagnostic device 25 first outputs a test signal that sets all of the drive signals a to d to logic "1" (all contacts are closed). At this time, since each contact is in a closed state, all current detection means 30 to 35 detect that current is flowing through these contacts (the output of the current detection means is a logic LL I
II). However, if all the outputs of the current detection means do not become the logic rr III, it is known that one of the contacts has a stuck-at-open fault. For example, the current detection means 30, 31, 33. .. If only one of the outputs of 34 is logic "O", it can be determined that the corresponding contact is in an open state. Further, if only the output of the current detecting means 32 is logic II OII, it can be determined that contact 4 or 5 is in the open state, and if only the output of the current detecting means 35 is logic II OII, contact 8 or 9 is in the open state. It can be determined that the is in the open state. However, all the outputs of the total current detection means are logic II OF+
In this case, all the contacts 2 to 9 are not in the open state, but the signal processing devices 17 to 20 are connected to the scram valve 11.
It is determined that a signal is being output for operation. This is because the probability that all contacts 2 to 9 will simultaneously become stuck in the open state is extremely low.

次に、診断装置25がa== 1107+とするテスト
信号を出力すると、これに応じて接点が正常に動作すれ
ば表1に示すパターンの電流検出結果が得られる。検出
結果がこのパターンと異なれば接点2、あるいは、4の
故障が検出できる。同様に、順次b=“O”、C=“0
”、d=”O”となるようテスト信号を印加して各電流
検出手段の出力である電流検出結果信号27の結果を表
1に対応させて評価することにより、各接点の健全性を
評価できる。この判定で、全電流検出手段の出力が論理
LL OITである場合には、前述と同様、信号処理装
置17〜20からスクラム弁1]、を動作すべく信号が
出力されていると判定し、誤診断を防止する。なお、信
号a −dを論理di □ IIにする具体的方法は診
断装置25からテスト信号26をスイッチ21〜24に
与え、スイッチの接点を接地側に切換えることによって
達成できる。また、信号a −dを“1”にすることは
、スイッチ21〜24を接地側に切換えないことによっ
て達成できる。
Next, when the diagnostic device 25 outputs a test signal such that a==1107+, if the contacts operate normally in response to this, a current detection result of the pattern shown in Table 1 will be obtained. If the detection result differs from this pattern, a failure of contact 2 or 4 can be detected. Similarly, sequentially b="O", C="0"
The soundness of each contact is evaluated by applying a test signal so that ", d = "O" and evaluating the results of the current detection result signal 27, which is the output of each current detection means, in accordance with Table 1. In this determination, if the output of the total current detection means is the logic LL OIT, it is determined that a signal is being output from the signal processing devices 17 to 20 to operate the scram valve 1, as described above. This prevents misdiagnosis.The specific method for converting the signals a-d to logic di□II is to apply the test signal 26 from the diagnostic device 25 to the switches 21 to 24 and switch the contacts of the switches to the ground side. Furthermore, setting the signals a to d to "1" can be achieved by not switching the switches 21 to 24 to the ground side.

診断装置25は各種の構成方法が考えられるが基本的に
は次の機能をもっておればよい。まず、信号a −dを
“1”にできること(具体的にはスイッチ21〜24を
接地側に切換えないこと)、次に、信号a、b、c、d
を順次論理tL OIIにできること。そして、」二記
いずれの場合にも、電流検出手段30〜35のすへての
出力が論理11011(接点2〜9に電流が流れていな
いこと)であれば、信号処理装置17〜20からトリッ
プ信号(スクラム弁11を動作させる信号)が出力され
たと判定できること。さらに、テスト信号に対して取込
んだ電流検出パターンを表1と比較して、接点2〜9の
健全性を判断できること。また、この結果を表示、ある
いは、出力できること。
The diagnostic device 25 can be configured in various ways, but basically it is sufficient if it has the following functions. First, the signals a, b, c, and d must be able to be set to "1" (specifically, the switches 21 to 24 must not be switched to the ground side).
can be made into logical tL OII sequentially. In either case, if all the outputs of the current detection means 30 to 35 are logic 11011 (no current flows through the contacts 2 to 9), the signal processing devices 17 to 20 It can be determined that a trip signal (a signal for operating the scram valve 11) has been output. Furthermore, the soundness of the contacts 2 to 9 can be determined by comparing the current detection pattern taken in response to the test signal with Table 1. Also, be able to display or output the results.

これらの機能を実現する診断装置の構成を第3図に示す
。これはマイクロプロセッシングユニットによって達成
される。この装置は、上記処理の手続きを格納している
ROM251と、その手続きを実行するCPU252と
、演算結果等を一次的に格納するRAM23、ステト信
号26を出力するテスト信号出力回路254と電流検出
結果信号27を取込む入力回路255と、診断結果を表
示、出力する診断結果出力回路256から成っており、
257はアドレスバス、258はデータバスである。
FIG. 3 shows the configuration of a diagnostic device that realizes these functions. This is achieved by a microprocessing unit. This device includes a ROM 251 that stores the above processing procedure, a CPU 252 that executes the procedure, a RAM 23 that temporarily stores calculation results, etc., a test signal output circuit 254 that outputs a STAT signal 26, and a current detection result. It consists of an input circuit 255 that takes in the signal 27, and a diagnostic result output circuit 256 that displays and outputs the diagnostic results.
257 is an address bus, and 258 is a data bus.

第4図ないし第7図は、ROM251に格納されている
命令に従ってCPU252が実行する処理をフローチャ
ート(一周期分)として示したものであり、診断装置2
5の処理機能である。第4図ないし第7図に示された同
じ符号(Q、R,S、T、U及びV)同士は、つながっ
ている。
4 to 7 are flowcharts (for one cycle) of the processing executed by the CPU 252 in accordance with the instructions stored in the ROM 251, and the diagnostic device 2
This is the processing function No. 5. The same symbols (Q, R, S, T, U, and V) shown in FIGS. 4 to 7 are connected to each other.

なお、第1図の実施例では、出力回路16を一個設けた
場合を示したが、これを複数個設け、それぞれ信号a 
−dによって駆動されるようにする場合には、各出力回
路に設ける電流検出手段からの電流検出結果信号を診断
装置で取込み、これが各回路毎に表1に示すパターンと
一致しているか否か判定して、各出力回路を構成する接
点の健全性をオンラインで判断できる。
Although the embodiment shown in FIG. 1 shows the case where one output circuit 16 is provided, a plurality of output circuits 16 are provided, and each output circuit 16 receives a signal a.
-d, the current detection result signal from the current detection means provided in each output circuit is taken in by a diagnostic device, and each circuit is checked to see if it matches the pattern shown in Table 1. The health of the contacts that make up each output circuit can be determined online.

本実施例では原子炉保護系を対象としたが、本発明はこ
れに限定されるものではなく、広く一般の冗長系に適用
できることは言うまでもない。
Although this embodiment deals with a nuclear reactor protection system, it goes without saying that the present invention is not limited thereto, and can be applied to a wide range of general redundant systems.

また、本発明の実施例の接点はリレー等の接点ばかりで
なく、トランジスタ接点(トランジスタのオン・オフの
機能)等の半導体素子であってもよいことは言うまでも
ないことである。
It goes without saying that the contacts in the embodiments of the present invention are not limited to contacts such as relays, but may also be semiconductor elements such as transistor contacts (transistor on/off function).

〔発明の効果〕〔Effect of the invention〕

本発明によれば、オンラインで2アウトオブ4回路を構
成する接点の健全性を判断することができる。
According to the present invention, it is possible to judge the health of contacts forming a 2-out-of-4 circuit online.

【図面の簡単な説明】[Brief explanation of drawings]

第1図は、本発明の一実施例の系統図、第2図は従来例
の系統図、第3図は診断装置の具体的構成図、第4図な
いし第7図はこの診断装置の処理フローチャートである
。 2〜9・・・接点、25・・・診断装置、26・・テス
ト信号、27・・電流検出結果信号、30〜35・・電
流検出手段。
Fig. 1 is a system diagram of an embodiment of the present invention, Fig. 2 is a system diagram of a conventional example, Fig. 3 is a specific configuration diagram of a diagnostic device, and Figs. 4 to 7 are processing diagrams of this diagnostic device. It is a flowchart. 2-9...Contact, 25...Diagnosis device, 26...Test signal, 27...Current detection result signal, 30-35...Current detection means.

Claims (1)

【特許請求の範囲】 1、第一の開閉手段と第二の開閉手段と第三の開閉手段
と第四の開閉手段を直列に接続し、第五の開閉手段と第
六の開閉手段と第七の開閉手段と第への開閉手段を直列
に接続し、前記第一の開閉手段と前記第二の開閉手段と
の接続点と前記第五の開閉手段と前記第六の開閉手段と
の接続点を接続し、前記第二の開閉手段と前記第三の開
閉手段の接続点と前記第六の開閉手段と前記第七の開閉
手段の接続点を接続し、前記第一の開閉手段と前記第六
の開閉手段の未接続点を互いに接続し、前記第四の開閉
手段と前記第への開閉手段の未接続点を互いに接続し、
かつ、前記第一の開示手段と前記第三の開閉手段に四つ
の駆動信号のうち第一の駆動信号を印加し、前記第二の
開閉手段と前記第七の開閉手段に第二の駆動信号を印加
し、前記第四の開閉手段と前記第五の開閉手段に第三の
駆動信号を印加し、前記第六の開閉手段と前記第への開
閉手段に第四の駆動信号を印加する2アウトオブ4回路
において、 前記第一の開閉手段、前記第二の開閉手段、前記第三の
開閉手段及び前記第四の開閉手段のいずれか一方、前記
第五の開閉手段、前記第六の開閉手段、前記第七の開閉
手段の開閉手段及び前記第への開閉手段のいずれか一方
に流れる電流を検出する手段を設け、各電流検出手段の
出力信号と開閉手段に順次印加するテスト信号とを比較
して開閉手段の健全性を判断する診断装置を設けたこと
を特徴とする2アウトオブ4回路の診断装置。
[Claims] 1. The first opening/closing means, the second opening/closing means, the third opening/closing means, and the fourth opening/closing means are connected in series, and the fifth opening/closing means, the sixth opening/closing means, and the third opening/closing means are connected in series. A seventh opening/closing means and a second opening/closing means are connected in series, and a connection point between the first opening/closing means and the second opening/closing means and a connection between the fifth opening/closing means and the sixth opening/closing means. a connecting point between the second opening/closing means and the third opening/closing means, a connecting point between the sixth opening/closing means and the seventh opening/closing means, and a connecting point between the first opening/closing means and the seventh opening/closing means; connecting the unconnected points of the sixth opening/closing means to each other, and connecting the unconnected points of the fourth opening/closing means and the third opening/closing means to each other;
and applying a first drive signal among the four drive signals to the first opening/closing means and the third opening/closing means, and applying a second driving signal to the second opening/closing means and the seventh opening/closing means. 2, applying a third drive signal to the fourth opening/closing means and the fifth opening/closing means, and applying a fourth driving signal to the sixth opening/closing means and the third opening/closing means. In the out-of-four circuit, any one of the first opening/closing means, the second opening/closing means, the third opening/closing means, and the fourth opening/closing means, the fifth opening/closing means, or the sixth opening/closing means. means for detecting a current flowing through either the opening/closing means of the seventh opening/closing means and the opening/closing means for the seventh opening/closing means, and an output signal of each current detection means and a test signal sequentially applied to the opening/closing means. A 2-out-of-4 circuit diagnostic device, characterized in that it is provided with a diagnostic device that compares and determines the soundness of the opening/closing means.
JP62125901A 1987-05-25 1987-05-25 Diagnostic device for two-out-of-four circuit Pending JPS63290978A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP62125901A JPS63290978A (en) 1987-05-25 1987-05-25 Diagnostic device for two-out-of-four circuit

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP62125901A JPS63290978A (en) 1987-05-25 1987-05-25 Diagnostic device for two-out-of-four circuit

Publications (1)

Publication Number Publication Date
JPS63290978A true JPS63290978A (en) 1988-11-28

Family

ID=14921711

Family Applications (1)

Application Number Title Priority Date Filing Date
JP62125901A Pending JPS63290978A (en) 1987-05-25 1987-05-25 Diagnostic device for two-out-of-four circuit

Country Status (1)

Country Link
JP (1) JPS63290978A (en)

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