JPH03277173A - Power interruption detecting circuit - Google Patents
Power interruption detecting circuitInfo
- Publication number
- JPH03277173A JPH03277173A JP7788790A JP7788790A JPH03277173A JP H03277173 A JPH03277173 A JP H03277173A JP 7788790 A JP7788790 A JP 7788790A JP 7788790 A JP7788790 A JP 7788790A JP H03277173 A JPH03277173 A JP H03277173A
- Authority
- JP
- Japan
- Prior art keywords
- voltage
- time point
- output
- resistor
- capacitor
- 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.)
- Granted
Links
- 238000001514 detection method Methods 0.000 claims abstract description 24
- 239000003990 capacitor Substances 0.000 abstract description 18
- 230000000630 rising effect Effects 0.000 abstract description 3
- 230000003287 optical effect Effects 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 3
- 238000009413 insulation Methods 0.000 description 3
- 230000003111 delayed effect Effects 0.000 description 2
- 238000002955 isolation Methods 0.000 description 2
- 230000007423 decrease Effects 0.000 description 1
Landscapes
- Rectifiers (AREA)
- Control Of Voltage And Current In General (AREA)
- Measurement Of Current Or Voltage (AREA)
- Emergency Protection Circuit Devices (AREA)
Abstract
Description
【発明の詳細な説明】
[産業上の利用分野]
この発明は、交流電源の停電を検出する停電検出回路に
関するものである。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a power outage detection circuit that detects a power outage of an AC power supply.
[従来の技術]
第4図は従来の停電検出回路を示す回路図であり、図に
おいて、(1)は交流電源、(2)は交流電源(1)か
ら出力される交流を整流するダイオードブリッジ、(2
a)はダイオードブリッジ(2)の正極性の出力端子、
(2b)はダイオードブリッジ(2)の負極性の出力端
子、(3)は電流制限用抵抗器、(4)は光絶縁素子、
例えば、フォトカブラ、(4a)はフォトカブラ(4)
の入力側の発光ダイオード、(4b)はフォトカブラ(
4)の出力側のNPN形のフォトトランジスタ、(5)
はツェナーダイオードであり、ダイオードブリッジ(2
)の正極性の出力端子(2a)は電流制限用抵抗(3)
を介してフォトカブラ(4)の入力側の発光ダイオード
(4a)の陽極に接続されている。フォトカブラ(4)
の入力側の発光ダイオード(4a)の陰極はツェナーダ
イオード(5)の陰極に接続され、ツェナーダイオード
(5)の陽極はダイオードブリッジ(2)の負極性の出
力端子(2b)に接続されている。(6)は正極性の直
流電源ライン、(7)はフォトカブラ(4)の出力側の
フォトトランジスタ(4b)のエミッタと接地間に接続
される抵抗器である。(8)は抵抗器、(9)は抵抗器
(8)と直列に接続されるコンデンサであり、この抵抗
器(8)とコンデンサ(9)との直列体は抵抗器(8)
側の一端がフォトトランジスタ(4b)のエミッタに接
続され、コンデンサ(9)側の一端は接地されている。[Prior Art] Figure 4 is a circuit diagram showing a conventional power outage detection circuit. In the figure, (1) is an AC power supply, and (2) is a diode bridge that rectifies the AC output from the AC power supply (1). ,(2
a) is the positive output terminal of the diode bridge (2),
(2b) is the negative output terminal of the diode bridge (2), (3) is the current limiting resistor, (4) is the optical isolation element,
For example, Photocabura (4a) is Photocabra (4)
The light emitting diode (4b) on the input side of the photocoupler (
4) NPN phototransistor on the output side, (5)
is a Zener diode, and the diode bridge (2
)'s positive output terminal (2a) is the current limiting resistor (3)
It is connected to the anode of the light emitting diode (4a) on the input side of the photocoupler (4) via the photocoupler (4). Photocabra (4)
The cathode of the light emitting diode (4a) on the input side of is connected to the cathode of the Zener diode (5), and the anode of the Zener diode (5) is connected to the negative output terminal (2b) of the diode bridge (2). . (6) is a positive DC power supply line, and (7) is a resistor connected between the emitter of the phototransistor (4b) on the output side of the photocoupler (4) and ground. (8) is a resistor, (9) is a capacitor connected in series with the resistor (8), and the series body of this resistor (8) and capacitor (9) is the resistor (8).
One end of the side is connected to the emitter of the phototransistor (4b), and one end of the capacitor (9) is grounded.
(10)は正極性の直流電源ライン、 (11)は電流
制限用抵抗器、(12)は電圧比較器、(12a)は電
圧比較器(12)の入力端子、(12b)は入力端子(
12a)の電圧に比べて小さい電圧が入力されると電圧
比較器(12)の出力が”1”となる電圧比較器(12
)の入力端子であり、入力端子(12alは抵抗器(8
)とコンデンサ(9)の直列体の抵抗器(8)とコンデ
ンサ(9)との接続点に接続され、入力端子(12b)
は電流制限用抵抗器(11)を介して直流電源ライン(
lO)に接続されている。(10) is the positive polarity DC power supply line, (11) is the current limiting resistor, (12) is the voltage comparator, (12a) is the input terminal of the voltage comparator (12), and (12b) is the input terminal (
When a voltage smaller than the voltage of voltage comparator (12a) is input, the output of voltage comparator (12) becomes "1".
), and the input terminal (12al is the input terminal of the resistor (8
) and the capacitor (9) connected to the connection point of the resistor (8) and the capacitor (9) in series, and the input terminal (12b)
is connected to the DC power line (
lO).
次に動作について第5図により説明する。115図にお
いて(5A)は交流電源mから出力される交流が全波整
流された波形としてのグイオードブリッジ(2)の出力
端子(2a)、(2b)間の電圧波形である。f501
1はツェナーダイオード(5)のツェナー電圧と発光ダ
イオード【4a)の順方向電圧の和の電圧を示し、この
電圧(501)を電圧波形(5^)が越えたとき発光ダ
イオード(4a)に電流が流れる。(5B)は発光タイ
オード(4a)に流れる電流に同期してフォトトランジ
スタ(4b)が導通し、フォトトランジスタ(4b)が
導通した結果、抵抗器(7)の両端に現われる電圧波形
を示している。 (5C)は電圧波形(5B)が抵抗器
(7)の両端に現われているときのコンデンサ(9)の
両端に現われる電圧波形であり、(502)は直流電源
ライン(lO)の電圧を示している。Next, the operation will be explained with reference to FIG. In FIG. 115, (5A) is a voltage waveform between the output terminals (2a) and (2b) of the guiode bridge (2) as a waveform obtained by full-wave rectification of the AC output from the AC power supply m. f501
1 indicates the voltage that is the sum of the Zener voltage of the Zener diode (5) and the forward voltage of the light emitting diode (4a), and when the voltage waveform (5^) exceeds this voltage (501), a current flows through the light emitting diode (4a). flows. (5B) shows the voltage waveform that appears across the resistor (7) as a result of the phototransistor (4b) becoming conductive in synchronization with the current flowing through the light emitting diode (4a) and the phototransistor (4b) becoming conductive. . (5C) is the voltage waveform appearing across the capacitor (9) when the voltage waveform (5B) appears across the resistor (7), and (502) indicates the voltage of the DC power line (lO). ing.
(5D)は電圧比較器(12)の出力電圧波形であり、
電圧波形(5C)が直流電源ライン(lO)の電圧(5
02)より大きいときは′l″ルベルが出力され、電圧
波形(5C)が直流電源ライン(lO)の電圧(502
)より小さいときは“0”レベルが出力されている。(5D) is the output voltage waveform of the voltage comparator (12),
The voltage waveform (5C) is the voltage (5C) of the DC power line (1O).
02), the 'l'' level is output, and the voltage waveform (5C) becomes the voltage (502) of the DC power line (lO).
), a "0" level is output.
ここで、抵抗器(8)、コンデンサ(9)の直列体の時
定数、抵抗器(7)、抵抗器(8)、コンデンサ(9)
の直列体の時定数、および、直流電源ライン(lO)の
電圧(502) 、の値を選ぶことにより、交流電源f
l)が正常な交流電圧を出力し、電圧波形(5B)が等
間隔のパルス波形になっているときは電圧比較器(12
)の出力を“1′″レベルを保ち、交流電源(])に停
電が発生したり、出力電圧が低下し、電圧波形(5B)
におけるパルスが発生しなくなったとき、もしくは等間
隔のパルスに欠落が生じたとき“0”レベルを出力する
ように構成することができる。Here, the time constant of the series body of resistor (8), capacitor (9), resistor (7), resistor (8), capacitor (9)
By selecting the time constant of the series body of and the voltage (502) of the DC power supply line (lO), the AC power supply f
When the voltage comparator (12) outputs a normal AC voltage and the voltage waveform (5B) is a pulse waveform with equal intervals
) is maintained at the "1'" level, and if a power outage occurs in the AC power supply (]) or the output voltage decreases, the voltage waveform (5B)
It can be configured to output a "0" level when pulses no longer occur, or when pulses at equal intervals are missing.
このとき、交流電源(11が正常時には“l”レベルを
出力し、停電もしくは電圧低下時には“0′″レベルを
出力する停電および電圧低下を検出する停電検出回路と
して動作することになる。At this time, when the AC power supply (11) is normal, it outputs the "L" level, and when there is a power outage or voltage drop, it outputs the "0'' level. It operates as a power outage detection circuit that detects power outages and voltage drops.
第4図に示される停電検出回路においては、第5図に示
され電圧波形(5C)は電圧波形(5B)におけるパル
スの立下り時点+503)より抵抗器(7)、抵抗器(
8)、およびコンデンサ(9)の直列体としての時定数
回路の時定数にもとづくコンデンサ(9)の両端の電圧
の立下り曲線(5041が直流電源ライン(lO)の電
圧(5021と交わる時点(505)までの時間内に再
び電圧波形(5^)が電圧(501)を越えないと停電
を検出するように構成されているので、電圧波形(5B
)におけるパルスの立上り時点(506)以降電圧波形
(5A)の電圧がOVになる近傍の時点(507)まで
の間に停電が発生しても、停電検出時点は、停電がない
場合において次に続いて発生するパルス波形の立下り時
点+508)以上に早くならない[発明が解決しようと
する課題]
従来の停電検出回路は以上のように構成されているので
、交流を整流した電圧波形(5A)が所定のレベルを越
えたときパルスが出力されるパルス波形としての電圧波
形(5B)の立下り時点(503)以降において、停電
が検出されるのは停電が発生しなかったとした時、次に
続(べきパルス波形の立下り時点(508)を過ぎた所
定の時点(SO5)に限られるので、特に停電発生時点
が上述の立下り時点(503)から電圧波形(5A)の
電圧がOVになる近傍の時点(507)の間のとき、停
電が発生してから停電検出信号が出力されるまでの時間
遅れが大きい。In the power failure detection circuit shown in FIG. 4, the voltage waveform (5C) shown in FIG. 5 is connected to the resistor (7) and the resistor (
8), and the falling curve of the voltage across the capacitor (9) based on the time constant of the time constant circuit as a series body of the capacitor (9) (the point at which 5041 intersects the voltage (5021) of the DC power supply line (lO)) If the voltage waveform (5^) does not exceed the voltage (501) again within the time until the voltage waveform (505), a power outage is detected.
Even if a power outage occurs between the time when the pulse rises (506) in [Problem to be solved by the invention] Since the conventional power failure detection circuit is configured as described above, the voltage waveform (5A) obtained by rectifying AC A power outage is detected after the falling point (503) of the voltage waveform (5B) as a pulse waveform in which a pulse is output when the voltage exceeds a predetermined level.Assuming that no power outage had occurred, then This is limited to a predetermined point (SO5) after the falling point (508) of the pulse waveform (508), so the power outage occurs especially when the voltage of the voltage waveform (5A) reaches OV from the falling point (503) mentioned above. When the time 507 is in the vicinity of , there is a large time delay from when a power outage occurs until the power outage detection signal is output.
この発明は上記のような課題を解決するためになされた
もので、停電検出時点が特定の時点f5051に限られ
ることなく、停電が発生してから停電検出信号が出力さ
れるまでの時間遅れの小さい停電検出回路を得ることを
目的とする。This invention was made in order to solve the above-mentioned problems, and the power outage detection point is not limited to a specific time point f5051, but the time delay from when a power outage occurs to when a power outage detection signal is output is fixed. The purpose is to obtain a small power failure detection circuit.
[S題を解決するための手段〕
この発明に係る停電検出回路は、交流を整流する整流器
と、この整流器の出力電圧に基づき入力電圧が供給され
る第1光絶縁素子とを有し、この第1光絶縁素子の入力
電流により制御される第1光絶縁素子の出力電流が所定
値以下となる状態が所定時間を越えたときに警報を出力
する停電検出回路において、
第1光絶縁素子の入力電流の少くとも一部が出力電流と
して流れ、第1光絶縁素子の出力電流の少くとも一部が
入力電流として流れる第2光絶縁素子を備えるようにし
たものである。[Means for Solving Problem S] A power outage detection circuit according to the present invention includes a rectifier that rectifies alternating current, and a first optical isolation element to which an input voltage is supplied based on the output voltage of the rectifier. In a power failure detection circuit that outputs an alarm when the output current of the first photo-insulating element, which is controlled by the input current of the first photo-insulating element, remains below a predetermined value for a predetermined time, The device includes a second photo-insulating element through which at least a part of the input current flows as an output current, and at least a part of the output current of the first optical-insulating element flows as an input current.
この発明に係る停電検出回路は、交流を整流する整流器
と5この整流器の出力電圧に基づき第1光絶縁素子の入
力電流が供給され、この入力電流の少くとも一部が出力
電流として流れ、第1光絶縁素子の出力電流の少くとも
一部が入力電流として流れる第2光絶縁素子を設けるこ
とにより、第1光絶縁素子は、停電がないときにおいて
非導通になる時点が遅延されるとともに停電発生時には
直ちに非導通になる。The power failure detection circuit according to the present invention includes a rectifier for rectifying alternating current, and an input current of the first photoinsulating element is supplied based on the output voltage of the rectifier, at least a part of this input current flows as an output current, and By providing the second opto-insulating element through which at least a part of the output current of the first opto-isolating element flows as an input current, the time point at which the first opto-insulating element becomes non-conducting is delayed when there is no power outage, and the point in time when the first opto-insulating element becomes non-conducting is delayed when there is no power outage. When this occurs, it immediately becomes non-conductive.
[発明の実施例〕
以下、この発明の一実施例を第1図により説明する。第
1図は第2光絶縁素子としての第2フオトカブラが追加
され、時定数を変えるため等の理由から抵抗器(7)、
抵抗器(8)、コンデンサ(9)の値を変えている他は
従来例を示す第4図と同一である。第1図において、(
4)は第1フオトカブラ、(40)は第2フオトカブラ
、f40a)は第2フオトカブラ(40)の入力側の発
光ダイオード、(40b)は第2フオトカブラ(40)
の出力側のフォトトランジスタであり、発光ダイオード
(40a)は、抵抗器(7)と抵抗器(8)の接続点と
第1フオトカブラ(4)のエミッタ間に、陽極が第1フ
オトカブラ(4)のエミッタに、陰極が抵抗器(7)お
よび抵抗器(8)の接続点にそれぞれ接続された状態で
挿入されている。また、フォトトランジスタf40b)
のコレクタはツェナーダイオード(5)の陰極に、エミ
ッタはツェナーダイオード(5)の陽極に接続されてい
る。[Embodiment of the Invention] An embodiment of the invention will be described below with reference to FIG. In Fig. 1, a second photocoupler as a second photoinsulating element is added, and for reasons such as changing the time constant, a resistor (7),
It is the same as FIG. 4 showing the conventional example except that the values of the resistor (8) and capacitor (9) are changed. In Figure 1, (
4) is the first photocoupler, (40) is the second photocoupler, f40a) is the light emitting diode on the input side of the second photocoupler (40), and (40b) is the second photocoupler (40).
The light emitting diode (40a) is a phototransistor on the output side of the photocoupler (4), and the anode is connected between the connection point of the resistor (7) and the resistor (8) and the emitter of the first photocoupler (4). The cathode is inserted into the emitter of the resistor (7) and the resistor (8) with the cathode connected to the connection point of the resistor (7) and the resistor (8), respectively. Also, phototransistor f40b)
The collector is connected to the cathode of the Zener diode (5), and the emitter is connected to the anode of the Zener diode (5).
次に、動作について第2図により説明する。第2図にお
いて(2^)は従来例として第5図に示された電圧波形
(5^)と同じである。(2B)は従来例として第5図
に示された電圧波形(5B)に相当する電圧波形であり
、電圧波形(5B)に比べて立上り時点は同一であり、
立下り時点が電圧波形(2A)の電圧がOV近くまで低
下したときになっている。第2図に示される電圧波形(
2B)の立下り時点が電圧波形(2A)の電圧がO■近
(に低下したときになっている理由は、第1フオトカブ
ラ(4)のフォトトランジスタ(4b)が−度導通する
と第2フオトカブラ(40)の発光ダイオードf40a
)に電流が流れ、フォトトランジスタ(40blが導通
し、ツェナーダイオード(5)が短絡されダイオードブ
リッジ(2)の出力端子(2a) 、 (2b)間の電
圧が小さくても発光ダイオード(4a)に電流が流れ、
第1フオトトランジスタ(4)の導通状態が維持される
ためである。(2C)は従来例として第5図に示された
電圧波形(5C)に相当する電圧波形であり、f203
1は第5図に示される曲線(504)に相当するコンデ
ンサ(9)の両端の電圧の立下り曲線である。曲線f2
031の立下りが曲線[504)に比べて急峻になって
いる理由は、コンデンサ(9)の放電開始時点f202
1が従来例における時点(5031より遅れた時点であ
るにもかかわらずコンデンサ(9)の両端の電圧が直流
電源ライン〔lO)の電圧(5021と等しくなる時点
(505)を同一時点にすればよいためである。(2D
)は第5図に示される電圧波形(5D)に相当する電圧
波形である。Next, the operation will be explained with reference to FIG. In FIG. 2, (2^) is the same as the voltage waveform (5^) shown in FIG. 5 as a conventional example. (2B) is a voltage waveform corresponding to the voltage waveform (5B) shown in FIG. 5 as a conventional example, and the rising point is the same as that of the voltage waveform (5B),
The falling point is when the voltage of the voltage waveform (2A) drops to near OV. The voltage waveform shown in Figure 2 (
The reason why the falling point of 2B) is when the voltage of the voltage waveform (2A) drops to near 0 is that when the phototransistor (4b) of the first photocoupler (4) conducts -degree, the second photocoupler (40) light emitting diode f40a
), current flows through the phototransistor (40bl), the Zener diode (5) is short-circuited, and even if the voltage between the output terminals (2a) and (2b) of the diode bridge (2) is small, the light emitting diode (4a) current flows,
This is because the conductive state of the first phototransistor (4) is maintained. (2C) is a voltage waveform corresponding to the voltage waveform (5C) shown in FIG. 5 as a conventional example, and f203
1 is a falling curve of the voltage across the capacitor (9), which corresponds to the curve (504) shown in FIG. curve f2
The reason why the fall of curve 031 is steeper than that of curve [504] is because the discharge start point of capacitor (9) is f202.
Even though 1 is later than the time point (5031) in the conventional example, if the time point (505) at which the voltage across the capacitor (9) becomes equal to the voltage (5021) of the DC power supply line [1O] is the same time point, then It is for good. (2D
) is a voltage waveform corresponding to the voltage waveform (5D) shown in FIG.
なお、電圧波形(2B)において、非停電時におけるパ
ルス波形の立上り時点(201)と立下り時点(202
1に相当する時点の間で停電が発生し、ダイオードブリ
ッジ(2)の出力端子(2a)、(2b)間の電圧が十
分小さ(なり、第1フオトカブラ(4)のフォトトラン
ジスタ(4b)が非導通状態になると、直ちに電圧波形
(2B)は立下り、コンデンサ(9)の両端の電圧は曲
線[203) と同じ傾斜の曲線を描いて下降する。In addition, in the voltage waveform (2B), the rising time (201) and the falling time (202) of the pulse waveform during non-power outage are shown.
1, the voltage between the output terminals (2a) and (2b) of the diode bridge (2) becomes sufficiently small (that is, the phototransistor (4b) of the first photocoupler (4) Immediately after becoming non-conductive, the voltage waveform (2B) falls, and the voltage across the capacitor (9) falls along a curve with the same slope as the curve [203].
従って、この場合時点(505)以前にコンデンサ(9
)の両端の電圧は直流電源ライン(]0)の電圧(50
2)と等しくなり、時点(5051より早い時点で停電
検出信号が出力される。Therefore, in this case, before the time (505), the capacitor (9
) is the voltage (50
2), and a power outage detection signal is output at a point earlier than the time point (5051).
なお、第1図においては、第1フオトカブラ(4)のフ
ォトトランジスタ(4b)が導通を開始するダイオード
ブリッジ(2)の出力端子(2al 、 f2b1間の
電圧の限界値はツェナーダイオード(5)のツェナー電
圧と発光ダイオード(4a)の順方向電圧の和の電圧で
あったが、第3図に示されるように、第1図におけるツ
ェナーダイオード〔5)の代りに抵抗器(13)を用い
、発光ダイオード(4a)の両端に抵抗器(14)を接
続し、抵抗器(3)、抵抗器(13)、および抵抗器(
14)の抵抗値を選択することにより上述の限界値を設
定するようにしてもよい。In FIG. 1, the limit value of the voltage between the output terminals (2al and f2b1) of the diode bridge (2) at which the phototransistor (4b) of the first photocoupler (4) starts conducting is determined by the voltage limit of the Zener diode (5). The voltage was the sum of the Zener voltage and the forward voltage of the light emitting diode (4a), but as shown in FIG. 3, a resistor (13) was used instead of the Zener diode [5] in FIG. A resistor (14) is connected to both ends of the light emitting diode (4a), and a resistor (3), a resistor (13), and a resistor (
The above-mentioned limit value may be set by selecting the resistance value of 14).
[発明の効果]
以上のように、この発明によれば停電検出回路を整流器
の出力電圧に基づき第1光絶縁素子の入力電流が供給さ
れ、この入力電流の少くとも一部が出力電流として流れ
、第1光絶縁素子の出力型流の少くとも一部が入力電流
として流れる第2光絶縁素子を設けることにより、第1
光絶縁素子は停電のないときは非導通になる時点が遅延
されるとともに停電発生時には直ちに非導通になるので
、停電発生後停電検出信号を発生するまでの時間遅れの
少いものが得られる効果がある。[Effects of the Invention] As described above, according to the present invention, the input current of the first opto-insulating element is supplied to the power failure detection circuit based on the output voltage of the rectifier, and at least a part of this input current flows as an output current. , by providing a second opto-insulating element through which at least a part of the output current of the first opto-insulating element flows as an input current,
Optical insulation elements delay the point at which they become non-conductive when there is no power outage, and immediately become non-conductive when a power outage occurs, so the effect is that there is less time delay until a power outage detection signal is generated after a power outage occurs. There is.
第1図はこの発明の一実施例による停電検出回路の接続
図、第2図は第1図に示される停電検出回路の動作タイ
ムチャート、第3図はこの発明の他の実施例による停電
検出回路の接続図である。
第4図は従来の停電検出回路の接続図、第5図は第4図
に示される停電検出回路の動作タイムチャートである。
(2)は整流器、(4)は第1光絶縁素子、(40)は
第2光絶縁素子。
なお、図中、同一符号は同一、または相当部分を示す。FIG. 1 is a connection diagram of a power failure detection circuit according to an embodiment of the present invention, FIG. 2 is an operation time chart of the power failure detection circuit shown in FIG. 1, and FIG. 3 is a power failure detection according to another embodiment of the present invention. It is a connection diagram of a circuit. FIG. 4 is a connection diagram of a conventional power failure detection circuit, and FIG. 5 is an operation time chart of the power failure detection circuit shown in FIG. (2) is a rectifier, (4) is a first optical insulation element, and (40) is a second optical insulation element. In addition, in the figures, the same reference numerals indicate the same or equivalent parts.
Claims (1)
き入力電流が供給される第1光絶縁素子とを有し、この
第1光絶縁素子の入力電流により制御される上記第1光
絶縁素子の出力電流が所定値以下となる状態が所定時間
を越えたときに警報を出力する停電検出回路において、 上記第1光絶縁素子の入力電流の少くとも一部が出力電
流として流れ、上記第1光絶縁素子の出力電流の少くと
も一部が入力電流として流れる第2光絶縁素子を備えた
ことを特徴とする停電検出回路。[Claims] The above-mentioned device comprises a rectifier that rectifies alternating current, and a first photo-insulating element to which an input current is supplied based on the output voltage of the rectifier, and is controlled by the input current of the first photo-insulating element. In a power failure detection circuit that outputs an alarm when the output current of the first photo-insulating element remains below a predetermined value for a predetermined period of time, at least a part of the input current of the first photo-insulating element is used as an output current. A power failure detection circuit comprising: a second photo-insulating element through which at least a part of the output current of the first photo-insulating element flows as an input current.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2077887A JP2546019B2 (en) | 1990-03-27 | 1990-03-27 | Power failure detection circuit |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP2077887A JP2546019B2 (en) | 1990-03-27 | 1990-03-27 | Power failure detection circuit |
Publications (2)
Publication Number | Publication Date |
---|---|
JPH03277173A true JPH03277173A (en) | 1991-12-09 |
JP2546019B2 JP2546019B2 (en) | 1996-10-23 |
Family
ID=13646586
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP2077887A Expired - Lifetime JP2546019B2 (en) | 1990-03-27 | 1990-03-27 | Power failure detection circuit |
Country Status (1)
Country | Link |
---|---|
JP (1) | JP2546019B2 (en) |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN113252966A (en) * | 2021-06-04 | 2021-08-13 | 广东福德电子有限公司 | Single-phase alternating current power supply signal detection circuit |
CN113433481A (en) * | 2021-06-04 | 2021-09-24 | 广东福德电子有限公司 | Circuit for rapidly detecting single-phase alternating current power supply signal |
Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS51129163A (en) * | 1975-05-06 | 1976-11-10 | Toshiba Corp | Wave form rectification circuit |
JPS602347U (en) * | 1983-06-15 | 1985-01-09 | 富士通機電株式会社 | Power outage detection circuit |
-
1990
- 1990-03-27 JP JP2077887A patent/JP2546019B2/en not_active Expired - Lifetime
Patent Citations (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS51129163A (en) * | 1975-05-06 | 1976-11-10 | Toshiba Corp | Wave form rectification circuit |
JPS602347U (en) * | 1983-06-15 | 1985-01-09 | 富士通機電株式会社 | Power outage detection circuit |
Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN113252966A (en) * | 2021-06-04 | 2021-08-13 | 广东福德电子有限公司 | Single-phase alternating current power supply signal detection circuit |
CN113433481A (en) * | 2021-06-04 | 2021-09-24 | 广东福德电子有限公司 | Circuit for rapidly detecting single-phase alternating current power supply signal |
Also Published As
Publication number | Publication date |
---|---|
JP2546019B2 (en) | 1996-10-23 |
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