JPH0767247A - No-load protective relay circuit - Google Patents
No-load protective relay circuitInfo
- Publication number
- JPH0767247A JPH0767247A JP5210039A JP21003993A JPH0767247A JP H0767247 A JPH0767247 A JP H0767247A JP 5210039 A JP5210039 A JP 5210039A JP 21003993 A JP21003993 A JP 21003993A JP H0767247 A JPH0767247 A JP H0767247A
- Authority
- JP
- Japan
- Prior art keywords
- contact
- protection relay
- load
- load protection
- circuit
- 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
Links
Landscapes
- Control Of Ac Motors In General (AREA)
- Keying Circuit Devices (AREA)
- Protection Of Generators And Motors (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、無負荷保護リレーによ
り主回路の不足電流を検出したときに電磁接触器を引き
外し動作させて電動機の無負荷保護をする無負荷保護リ
レー回路に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a no-load protection relay circuit for tripping an electromagnetic contactor to operate a no-load protection of an electric motor when an under-current protection relay detects an undercurrent in a main circuit.
【０００２】[0002]
【従来の技術】例えばコントロールセンタは、電動機の
運転と停止制御及び保護を目的とした単位装置を多数収
納し、発電所や一般産業の補機の集中制御に用いられ
る。図２にこの種の単位装置の一般的な回路図を示す。
図２において、負荷である電動機２が接続された主回路
には、電源母線側から順に配線用遮断器３、電磁接触器
４過電流継電器５及び電流検出器６が設けられている。
配線用遮断器３の負荷側と電磁接触器４の電源側との間
の２相間には操作変圧器７が接続されている。操作変圧
器７の二次側は操作回路用電源として、母線８，９に印
加される。2. Description of the Related Art For example, a control center accommodates a large number of unit devices for the purpose of operating and stopping control and protection of electric motors, and is used for centralized control of auxiliary equipment in power plants and general industries. FIG. 2 shows a general circuit diagram of this type of unit device.
In FIG. 2, the main circuit to which the electric motor 2 as a load is connected is provided with a circuit breaker 3, a magnetic contactor 4, an overcurrent relay 5, and a current detector 6 in order from the power source bus side.
An operation transformer 7 is connected between the two phases between the load side of the wiring breaker 3 and the power source side of the electromagnetic contactor 4. The secondary side of the operating transformer 7 is applied to the buses 8 and 9 as a power source for the operating circuit.
【０００３】この母線８にこれを一方の電源線として、
起動操作スイッチ１０、電磁接触器４の接点１２ａ1 、
瞬停再始動リレー１３の接点１３ａ、表示灯１４，１５
に直列接続された電磁接触器４の接点１２ｂ，１２ａ
3 、無負荷保護リレー１８の接点１８ａ、無負荷保護リ
レー１８の各一端が接続され、起動操作スイッチ１０、
電磁接触器４の接点１２ａ1 、瞬停再始動リレー１３の
接点１３ａの各他端は並列接続される。This bus bar 8 is used as one power source line,
Start operation switch 10, contact 12a 1 of electromagnetic contactor 4,
Contact 13a of instantaneous power failure restart relay 13 and indicator lights 14 and 15
Contacts 12b, 12a of the electromagnetic contactor 4 connected in series to the
3 , the contact 18a of the no-load protection relay 18, each end of the no-load protection relay 18 is connected, the start operation switch 10,
The other ends of the contact 12a 1 of the electromagnetic contactor 4 and the contact 13a of the instantaneous power failure restart relay 13 are connected in parallel.
【０００４】また停止操作スイッチ１１、オンディレー
タイマ１７の接点１７ａ、電磁接触器４の励磁コイル１
２は起動操作スイッチ１０と直列に接続され、励磁コイ
ル１２と瞬停再始動リレー１３とは並列に接続されてい
る。無負荷保護リレー１８の接点１８ａには、直列接続
された電磁接触器４の接点１２ａ2 およびオフディレー
タイマ１６と、直列接続されたオフディレータイマ１６
の接点１６ａおよびオンディレータイマ１７との並列回
路が接続される。母線９には、励磁コイル１２、瞬停再
始動リレー１３、表示灯１４，１５、オフディレータイ
マ１６、オンディレータイマ１７、無負荷保護リレー１
８の各一端が接続される。Further, the stop operation switch 11, the contact point 17a of the on-delay timer 17, the exciting coil 1 of the electromagnetic contactor 4
2 is connected in series with the startup operation switch 10, and the exciting coil 12 and the instantaneous power failure restart relay 13 are connected in parallel. The contact 18a of the no-load protection relay 18 includes a contact 12a 2 of the electromagnetic contactor 4 and an off-delay timer 16 connected in series, and an off-delay timer 16 connected in series.
A parallel circuit with the contact point 16a and the on-delay timer 17 is connected. Exciting coil 12, instantaneous power failure restart relay 13, indicator lights 14, 15, off-delay timer 16, on-delay timer 17, and no-load protection relay 1 are provided on bus bar 9.
Each one end of 8 is connected.
【０００５】無負荷保護リレー１８の接点１８ａは通常
時には電磁接触器４の接点１２ａ2およびオフディレー
タイマ１６に接続される。不足電流検出時は無負荷保護
リレー１８の接点１８ａが切り替わり、オフディレータ
イマ１６の接点１６ａおよびオンディレータイマ１７に
接続される。オンディレータイマ１７が励磁されると、
一定時間後、電磁接触器４の励磁コイル１２がオンディ
レータイマ１７の接点１７ａの開路により消磁となり、
主回路１の電磁接触器４が引き外され、電動機２が不足
電流（無負荷）から保護される。The contact 18a of the no-load protection relay 18 is normally connected to the contact 12a 2 of the electromagnetic contactor 4 and the off-delay timer 16. When the undercurrent is detected, the contact 18a of the no-load protection relay 18 is switched and connected to the contact 16a of the off-delay timer 16 and the on-delay timer 17. When the on-delay timer 17 is excited,
After a certain time, the exciting coil 12 of the electromagnetic contactor 4 is demagnetized by opening the contact 17a of the on-delay timer 17,
The electromagnetic contactor 4 of the main circuit 1 is pulled out, and the electric motor 2 is protected from undercurrent (no load).
【０００６】停止表示の表示灯１４は電磁接触器４の開
路により接点１２ｂを介して点灯され、運転表示である
表示灯１５は電磁接触器４の閉路により接点１２ａ3 を
介して点灯される。The stop indicator light 14 is illuminated via the contact 12b when the electromagnetic contactor 4 is open, and the operation indicator light 15 is illuminated via the contact 12a 3 when the electromagnetic contactor 4 is closed.
【０００７】[0007]
【発明が解決しようとする課題】ところで、このような
電動機の無負荷運転を保護する無負荷保護リレー回路に
おいて、無負荷保護リレー１８の接点１８ａが振動等で
チャタリングすると、電磁接触器４が開閉を繰り返すた
め、負荷である電動機２も運転と停止を繰り返し、イン
チング運転を行う問題があった。また無負荷保護リレー
１８の接点１８ａの動作状態を確認できない欠点があっ
た。By the way, in such a no-load protection relay circuit for protecting the no-load operation of the electric motor, when the contact 18a of the no-load protection relay 18 chatters due to vibration or the like, the electromagnetic contactor 4 opens and closes. Therefore, there is a problem in that the inching operation is performed by repeating the operation and stop of the electric motor 2 which is the load. Further, there is a drawback that the operating state of the contact 18a of the no-load protection relay 18 cannot be confirmed.
【０００８】そこで本発明の第１の目的は、無負荷保護
リレーの接点のチャタリングによる電動機のインチング
運転を防止することのできる無負荷保護リレー回路を提
供することにある。本発明の第２の目的は、第１の目的
に加えて無負荷保護リレーの接点の動作状態を確認でき
る無負荷保護リレー回路を提供することにある。Therefore, a first object of the present invention is to provide a no-load protection relay circuit capable of preventing the inching operation of the electric motor due to chattering of the contacts of the no-load protection relay. A second object of the present invention is to provide a no-load protection relay circuit capable of confirming the operating state of the contacts of the no-load protection relay in addition to the first object.
【０００９】[0009]
【課題を解決するための手段】本発明による無負荷保護
リレー回路は、電動機が接続された主回路に電磁接触器
及び電流検出器を設け、電流検出器で主回路の不足電流
を検出すると、無負荷保護リレーを動作させて電磁接触
器を引き外し動作させ、電動機の無負荷運転を保護する
無負荷保護リレー回路において、電磁接触器を引き外す
タイマ又は補助リレーの接点を無負荷保護リレーの接点
と並列に接続したバイパス回路を設けたことを特徴とす
る（請求項１）。加えて無負荷保護リレーの接点に表示
灯をそれぞれ直列に接続して無負荷保護リレーの動作状
態を表示する回路を設けたことを特徴とする（請求項
２）。In the no-load protection relay circuit according to the present invention, an electromagnetic contactor and a current detector are provided in a main circuit to which an electric motor is connected, and when an undercurrent of the main circuit is detected by the current detector, In the no-load protection relay circuit that operates the no-load protection relay to trip the magnetic contactor to protect the motor's no-load operation, the contact of the timer or auxiliary relay that disconnects the magnetic contactor is connected to the no-load protection relay. A bypass circuit connected in parallel with the contact is provided (Claim 1). In addition, a circuit for connecting the indicator lights to the contacts of the no-load protection relay in series and displaying the operating state of the no-load protection relay is provided (claim 2).
【００１０】[0010]
【作用】電動機が無負荷運転になると、主回路に不足電
流が流れ、主回路に設けた電流検出器で検出される。す
ると、無負荷保護リレーが動作して電磁接触器を引き外
し動作させ主回路を開路するので、電動機は無負荷運転
から保護される。このとき、無負荷保護リレーの接点が
チャタリングしてもバイパス回路で確実に電磁接触器を
引き外し動作させ主回路を開路させる（請求項１）。ま
た無負荷保護リレーの接点動作状態を表示することがで
きる（請求項２）。When the motor is in no-load operation, an undercurrent flows in the main circuit and is detected by the current detector provided in the main circuit. Then, the no-load protection relay operates and the electromagnetic contactor is tripped and operated to open the main circuit, so that the electric motor is protected from no-load operation. At this time, even if the contact of the no-load protection relay chatters, the bypass circuit reliably trips the electromagnetic contactor to operate and opens the main circuit (claim 1). Further, the contact operating state of the no-load protection relay can be displayed (claim 2).
【００１１】[0011]
【実施例】図１は本発明の一実施例を示す回路図であ
る。１は負荷である電動機２に電源を供給する三相の主
回路で、この主回路１には、配線用遮断器３、電磁接触
器４、過電流継電器５、主回路電流を検出する電流検出
器６が主回路器具として介在されている。配線用遮断器
３の負荷側と電磁接触器４の電源側との間の２相間には
操作変圧器７が接続され、その二次側は操作回路用電源
として母線８と９に印加される。この母線８にこれを一
方の電源線として起動操作スイッチ１０、電磁接触器４
の接点１２ａ1 、瞬停再始動リレー１３の接点１３ａ、
無負荷保護リレー１８の接点１８ａ、無負荷保護リレー
１８の接点１８ａのバイパス接点であるオンディレータ
イマ１７の接点１７ｂ、無負荷保護リレー１８の各一端
が接続され、起動操作スイッチ１０、電磁接触器４の接
点１２ａ1 、瞬停再始動リレー１３の接点１３ａの各他
端は並列接続されている。FIG. 1 is a circuit diagram showing an embodiment of the present invention. Reference numeral 1 is a three-phase main circuit that supplies power to a motor 2 that is a load. The main circuit 1 includes a circuit breaker for wiring 3, an electromagnetic contactor 4, an overcurrent relay 5, and a current detection for detecting the main circuit current. The device 6 is interposed as a main circuit device. An operation transformer 7 is connected between two phases between the load side of the circuit breaker 3 for wiring and the power source side of the electromagnetic contactor 4, and the secondary side thereof is applied to buses 8 and 9 as a power source for an operation circuit. . This bus bar 8 uses this as one power supply line for a start operation switch 10, an electromagnetic contactor 4
Contact 12a 1 , contact 13a of the instantaneous power failure restart relay 13,
A contact 18a of the no-load protection relay 18, a contact 17b of an on-delay timer 17 that is a bypass contact of the contact 18a of the no-load protection relay 18, and one end of each of the no-load protection relay 18 are connected, and a start operation switch 10 and an electromagnetic contactor are connected. The other ends of the contact 12a 1 of No. 4 and the contact 13a of the restart relay 13 are connected in parallel.
【００１２】また停止操作スイッチ１１、オンディレー
タイマ１７の接点１７ａ、電磁接触器４の励磁コイル１
２は起動操作スイッチ１０と直列に接続され、励磁コイ
ル１２と瞬停再始動リレー１３とは並列に接続されてい
る。無負荷保護リレー１８の接点１８ａは電磁接触器４
の接点１２ａ2 とオフディレータイマ１６の直列回路
と、オフディレータイマ１６の接点１６ａとオンディレ
ータイマ１７の直列回路とに切り替え可能に接続され
る。無負荷保護リレー１８の接点１８ａは通常時には電
磁接触器４の接点１２ａ2 およびオフディレータイマ１
６と直列に接続される。不足電流検出時は無負荷保護リ
レー１８の接点１８ａの切り替え動作によりオフディレ
ータイマ１６の接点１６ａおよびオンディレータイマ１
７と直列に接続される。運転表示である表示灯１５はオ
フディレータイマ１６と並列に接続され、停止表示であ
る表示灯１４は無負荷保護リレー１８の接点１８ａと直
列に接続され、且つ接点１６ａおよびオンディレータイ
マ１７と並列に接続されている。Further, the stop operation switch 11, the contact point 17a of the on-delay timer 17, the exciting coil 1 of the electromagnetic contactor 4
2 is connected in series with the startup operation switch 10, and the exciting coil 12 and the instantaneous power failure restart relay 13 are connected in parallel. The contact 18a of the no-load protection relay 18 is the electromagnetic contactor 4
A switch 12a 2 and a series circuit of the off-delay timer 16 and a series circuit of the contact 16a of the off-delay timer 16 and the on-delay timer 17 are switchably connected. Normally, the contact 18a of the no-load protection relay 18 is the contact 12a 2 of the electromagnetic contactor 4 and the off-delay timer 1
6 is connected in series. When an undercurrent is detected, the contact 18a of the no-load protection relay 18 is switched to change the contact 16a of the off-delay timer 16 and the on-delay timer 1.
7 is connected in series. The operation indicator lamp 15 is connected in parallel with the off-delay timer 16, the stop indicator lamp 14 is connected in series with the contact 18a of the no-load protection relay 18, and in parallel with the contact 16a and the on-delay timer 17. It is connected to the.
【００１３】母線９には、励磁コイル１２、瞬停再始動
リレー１３、表示灯１５、オフディレータイマ１６、オ
ンディレータイマ１７、表示灯１４、無負荷保護リレー
１８の各一端が接続されている。To the bus bar 9, one ends of an exciting coil 12, an instantaneous power failure restart relay 13, an indicator lamp 15, an off-delay timer 16, an on-delay timer 17, an indicator lamp 14, and a no-load protection relay 18 are connected. .
【００１４】次に上記構成の作用について説明する。起
動操作スイッチ１０をＯＮすると励磁コイル１２が励磁
され電磁接触器４を閉路するので、電動機２が運転され
る。停止操作スイッチ１１がＯＦＦされると励磁コイル
１２が消磁され電磁接触器４を開路するので、電動機２
が停止される。電動機２が正常運転のときは、無負荷保
護リレー１８の接点１８ａが電磁接触器４の接点１２ａ
2 を介してオフディレータイマ１６を常時励磁してお
り、運転表示である表示灯１５が点灯されている。電動
機２が無負荷運転になると、主回路１に不足電流が流れ
電流検出器６により不足電流が検出される。すると、無
負荷保護リレー１８が動作してその接点１８ａが切り替
わり、オンディレータイマ１７がオフディレータイマ１
６の接点１６ａを介して励磁される。オンディレータイ
マ１７の接点１７ａは一定時間後に開動作して励磁コイ
ル１２を消磁するので、電磁接触器４は開路され電動機
２の無負荷運転の保護を行う。この場合電磁接触器４が
開路すると、オンディレータイマ１７の接点１７ｂは閉
動作し、オフディレータイマ１６の接点１６ａをバイパ
スする回路を構成するので、無負荷保護リレー１８の接
点１８ａが振動等でチャタリングしても確実に電磁接触
器４を開路できる。またオンディレータイマ１７の接点
１７ｂの閉動作により停止表示である表示灯１４が点灯
される。Next, the operation of the above configuration will be described. When the start operation switch 10 is turned on, the exciting coil 12 is excited and the electromagnetic contactor 4 is closed, so that the electric motor 2 is operated. When the stop operation switch 11 is turned off, the exciting coil 12 is demagnetized and the electromagnetic contactor 4 is opened.
Is stopped. When the electric motor 2 is operating normally, the contact 18a of the no-load protection relay 18 is the contact 12a of the electromagnetic contactor 4.
The off-delay timer 16 is constantly excited via 2 and the indicator lamp 15 which is an operation display is turned on. When the electric motor 2 is in a no-load operation, an undercurrent flows in the main circuit 1 and the undercurrent is detected by the current detector 6. Then, the no-load protection relay 18 operates to switch its contact 18a, and the on-delay timer 17 turns off-delay timer 1
It is excited through the contact 16a of the No. 6 terminal. The contact 17a of the on-delay timer 17 opens after a certain period of time to demagnetize the exciting coil 12, so that the electromagnetic contactor 4 is opened to protect the motor 2 from no-load operation. In this case, when the electromagnetic contactor 4 is opened, the contact point 17b of the on-delay timer 17 is closed and a circuit that bypasses the contact point 16a of the off-delay timer 16 is formed, so that the contact point 18a of the no-load protection relay 18 is vibrated. Even if chattering occurs, the electromagnetic contactor 4 can be surely opened. Further, the closing operation of the contact point 17b of the on-delay timer 17 turns on the indicator light 14 which is a stop display.
【００１５】このように、操作スイッチ１０，１１で電
磁接触器４の開閉を行うと共に無負荷保護も行うが、こ
の場合、無負荷保護リレー１８の接点１８ａが振動等で
チャタリングしても確実に電磁接触器４を開路でき、電
動機２のインチング運転を防止できる。また無負荷保護
リレー１８の接点１８ａを介して表示灯１４，１５が点
灯されるので、無負荷保護リレー１８の接点動作も確認
できる。尚、上記実施例のオンディレータイマ１７を補
助リレーで構成しても上記実施例と同様の効果を得るこ
とができる。As described above, the operation switches 10 and 11 open and close the electromagnetic contactor 4 as well as provide no-load protection. In this case, even if the contact 18a of the no-load protection relay 18 chatters due to vibration or the like, the contact is surely performed. The electromagnetic contactor 4 can be opened, and the inching operation of the electric motor 2 can be prevented. Further, since the indicator lamps 14 and 15 are turned on via the contact 18a of the no-load protection relay 18, the contact operation of the no-load protection relay 18 can be confirmed. Even if the on-delay timer 17 of the above-described embodiment is configured by an auxiliary relay, the same effect as that of the above-described embodiment can be obtained.
【００１６】[0016]
【発明の効果】請求項１記載の本発明によれば、無負荷
保護リレーの接点がチャタリングを生じても電磁接触器
の開閉を繰り返すことなく確実に開路でき電動機のイン
チング運転を防止できる。また請求項２記載の本発明に
よれば、無負荷保護リレーの接点の動作も確認できる。According to the first aspect of the present invention, even if chattering occurs in the contacts of the no-load protection relay, the electromagnetic contactor can be opened reliably without repeating opening and closing, and the inching operation of the electric motor can be prevented. Further, according to the present invention described in claim 2, the operation of the contact of the no-load protection relay can be confirmed.
【図１】本発明による無負荷保護リレー回路の一実施例
を示す回路図FIG. 1 is a circuit diagram showing an embodiment of a no-load protection relay circuit according to the present invention.
【図２】従来例を示す図１相当図FIG. 2 is a view corresponding to FIG. 1 showing a conventional example.
図面中、１は主回路、２は電動機、３は配線用遮断器、
４は電磁接触器、５は過電流継電器、６は電流検出器、
１０は起動操作スイッチ、１１は停止操作スイッチ、１
２は励磁コイル、１２ａ1 ，１２ａ2 ，１２ａ3 は励磁
コイルの接点、１４、１５は表示灯、１６はオフディレ
ータイマ、１６ａはオフディレータイマの接点、１７は
オンディレータイマ、１７ａ，１７ｂはオンディレータ
イマの接点、１８は無負荷保護リレー、１８ａは無負荷
保護リレーの接点を示す。In the drawing, 1 is a main circuit, 2 is an electric motor, 3 is a circuit breaker for wiring,
4 is an electromagnetic contactor, 5 is an overcurrent relay, 6 is a current detector,
10 is a start operation switch, 11 is a stop operation switch, 1
2 is an excitation coil, 12a 1 , 12a 2 and 12a 3 are excitation coil contacts, 14 and 15 are indicator lights, 16 is an off-delay timer, 16a is an off-delay timer contact, 17 is an on-delay timer, and 17a and 17b are An on-delay timer contact, 18 is a no-load protection relay, and 18a is a no-load protection relay contact.
Claims (2)
及び電流検出器を設け、前記電流検出器で主回路の不足
電流を検出すると、無負荷保護リレーを動作させて前記
電磁接触器を引き外し動作させ、前記電動機の無負荷運
転を保護する無負荷保護リレー回路において、前記電磁
接触器を引き外すタイマ又は補助リレーの接点を前記無
負荷保護リレーの接点と並列に接続したバイパス回路を
設けたことを特徴とする無負荷保護リレー回路。1. An electromagnetic contactor and a current detector are provided in a main circuit to which an electric motor is connected, and when an undercurrent of the main circuit is detected by the current detector, a no-load protection relay is operated to operate the electromagnetic contactor. In a no-load protection relay circuit that trips and protects the no-load operation of the electric motor, a bypass circuit in which a contact of a timer or an auxiliary relay that trips the electromagnetic contactor is connected in parallel with a contact of the no-load protection relay A no-load protection relay circuit characterized by being provided.
ぞれ直列に接続して無負荷保護リレーの動作状態を表示
する回路を設けたことを特徴とする請求項１記載の無負
荷保護リレー回路。2. The no-load protection relay circuit according to claim 1, further comprising a circuit for connecting an indicator lamp to each contact of the no-load protection relay in series to display an operating state of the no-load protection relay. .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5210039A JPH0767247A (en) | 1993-08-25 | 1993-08-25 | No-load protective relay circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP5210039A JPH0767247A (en) | 1993-08-25 | 1993-08-25 | No-load protective relay circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0767247A true JPH0767247A (en) | 1995-03-10 |
Family
ID=16582798
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP5210039A Pending JPH0767247A (en) | 1993-08-25 | 1993-08-25 | No-load protective relay circuit |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0767247A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20000060656A (en) * | 1999-03-18 | 2000-10-16 | 윤문수 | An apparatus for controlling the load applied to motor control center unit |
| CN112844653A (en) * | 2020-12-31 | 2021-05-28 | 济南重工股份有限公司 | Transmission control device of ball mill |
-
1993
- 1993-08-25 JP JP5210039A patent/JPH0767247A/en active Pending
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20000060656A (en) * | 1999-03-18 | 2000-10-16 | 윤문수 | An apparatus for controlling the load applied to motor control center unit |
| CN112844653A (en) * | 2020-12-31 | 2021-05-28 | 济南重工股份有限公司 | Transmission control device of ball mill |
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