JPS6039315A - Overcurrent protecting relaying device - Google Patents

Abstract

(57)【要約】本公報は電子出願前の出願データであるた
め要約のデータは記録されません。(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

【発明の詳細な説明】 〔発明の利用分野〕 本発明は電動機の過電流保護装置に係り、特に、起動時
間の長い電動機の保護に最適な保護装置に関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an overcurrent protection device for an electric motor, and particularly to a protection device that is most suitable for protecting an electric motor that takes a long startup time.

〔発明の背景〕[Background of the invention]

従来、電動機の過電流保護は電動機の起動時限を逃げる
ため、動作時間の長い継電器で動作されでいた。ところ
が、近年、起動時間の非常に長い電動機が出現し・従来
の継電器では起動時に保護　′継電器が誤動作してしま
うか、又は、・過電流継電器動作後、更に、限時継電器
で動作時限を遅らす方式が採られている。しかし、保護
継電器の動作後、限時継電器で動作時限を遅らすことに
より。Conventionally, overcurrent protection for motors has been performed using relays with long operating times in order to avoid the motor start-up time limit. However, in recent years, motors with extremely long startup times have appeared, and conventional relays have either caused the protection relay to malfunction during startup, or, after the overcurrent relay has activated, a time-limited relay is used to further delay the activation time. is taken. However, by delaying the operation time in a time-limited relay after the operation of the protective relay.

過電流継電器が熱的な焼損をするか、又は、電動機自身
の事故を拡大してしまう欠点があった。There is a drawback that the overcurrent relay may suffer thermal burnout or cause an accident in the motor itself.

第１図は従来の主回路図で、１は電源、２は回路遮断器
、３は負荷の電動機、４は変流器、５は長時限動作形過
電流継電器である。第２図はこの保護装置の動作回路図
で、６が直流制御電源で、この電源より保護継電器５の
動作接点５−１が閉じ、補助継電器７が動作して保護継
電器の拘束電流検出用接点５−２が閉じると、主回路遮
断器２の４外し線輪２−１を励磁し、主回路遮断器を４
外して電源を遮断し、電動機を停止する。７−１は補助
継電器７が励磁されると、閉じるＡ接点である。館３図
はこれ等保護装置の動作協調図で、横軸に電流値ｉ、縦
軸に時間Ｔをとると８が電動機３の起動特性、９が電動
機の許容熱特性、１０が保詣継電器５の動作特性で、Ａ
部で電動機起動時保＠継電器５が誤動作する。即ち、主
回路電源を断って、電動機３を停止させる。FIG. 1 is a conventional main circuit diagram, in which 1 is a power supply, 2 is a circuit breaker, 3 is a load motor, 4 is a current transformer, and 5 is a long-time operating type overcurrent relay. Fig. 2 is an operating circuit diagram of this protective device, in which 6 is a DC control power supply, which closes the operating contact 5-1 of the protective relay 5, and the auxiliary relay 7 operates to connect the protective relay's restraining current detection contact. When 5-2 is closed, the 4-removal coil 2-1 of the main circuit breaker 2 is energized, and the main circuit breaker 4 is closed.
Remove it, cut off the power, and stop the motor. 7-1 is an A contact that closes when the auxiliary relay 7 is excited. Figure 3 is an operational coordination diagram of these protection devices, where the horizontal axis is the current value i and the vertical axis is the time T. 8 is the starting characteristic of the motor 3, 9 is the permissible thermal characteristic of the motor, and 10 is the protection relay. With the operating characteristics of 5, A
When the motor is started, the relay 5 malfunctions. That is, the main circuit power is cut off and the electric motor 3 is stopped.

〔発明の目的〕[Purpose of the invention]

本発明の目的は、被保護機器の電動機の起動特性及び、
許容熱特性に合致した最適な保護装置を提供するにある
。The object of the present invention is to improve the starting characteristics of a motor of a protected device,
The goal is to provide the optimal protection device that meets the permissible thermal characteristics.

〔発明の概要〕[Summary of the invention]

本発明は電動機の起動電流値よりも大き々電流域におい
て早期に動作するように、主回路設置の変流器の二次回
路へ補助変流器を挿入し、電流を半減することにより、
通常の動作値の短時限形過電流継電器で従来の長時限動
作形過電流継電器と組合せて、最適保護をするようにし
たものである。The present invention inserts an auxiliary current transformer into the secondary circuit of the current transformer installed in the main circuit to reduce the current by half so that the motor operates earlier in a current range that is much larger than the starting current value of the motor.
This is a short-time overcurrent relay with a normal operating value, which is combined with a conventional long-time overcurrent relay to provide optimal protection.

〔発明の実施例〕[Embodiments of the invention]

本発明は、第４図に示すように、従来の回路構成に変流
器４の二次回路側へ補助変流器１１を設置し、その補助
変流器の二次回路へ短時限動作形過電流継電器１２ｆ：
設置する。更に、第５図にこれ等の制御回路図を示す。As shown in FIG. 4, the present invention installs an auxiliary current transformer 11 on the secondary circuit side of the current transformer 4 in the conventional circuit configuration, and connects the secondary circuit of the auxiliary current transformer to a short-time operation type Current relay 12f:
Install. Further, FIG. 5 shows a diagram of these control circuits.

従来の長時限形保獲継電器５の動作接点５−１の後へ限
時継電器１３を設置し、限時継電器１３の整定時間後動
作する接点１３−１により、補助継電器７を励磁して・
遮断器２の引外し線輪２−１を励磁して主回路を遮断し
、電動機３を停止する。この動作協調図を第６図に示す
。第６図も第３図同様に配置され、保護継電器の動作特
性１０が、限時継電器１３で遅延された動作特性を１０
−１に示す。更に、追設された短時限形過電流継電器１
２の動作特性１４の組合せによる保護協調を１０−１と
１４に示す。A time limit relay 13 is installed after the operating contact 5-1 of the conventional long time limit type retention relay 5, and the auxiliary relay 7 is excited by the contact 13-1 that operates after the settling time of the time limit relay 13.
The trip wire 2-1 of the circuit breaker 2 is excited to interrupt the main circuit and the motor 3 is stopped. This motion coordination diagram is shown in FIG. FIG. 6 is arranged in the same manner as in FIG. 3, and the operating characteristic 10 of the protective relay is 10
-1. Furthermore, an additional short-time overcurrent relay 1
10-1 and 14 show protection cooperation based on a combination of the two operating characteristics 14.

又、第５図に示すように遮断器２の閉接点２−２により
、起動判定限時継電器１５を追設し、その接点１５−１
を限時継電器１３の動作接点１３−１と並列接続して、
補助継電器７へ接続することにより、起動後、即ち、運
転中の過電流保護は当初の長時限形継電器の動作特性ｌ
Ｏと、追設された短時限形継電器の動作特性１４の組合
せで早期に検出動作させ、遮断器２の引外し線輪２−１
を励磁することによシ、事故被害の僅少の内、主回路電
源を遮断して電動機３を停止する。Further, as shown in FIG. 5, a starting judgment time limit relay 15 is additionally installed using the closing contact 2-2 of the circuit breaker 2, and its contact 15-1
is connected in parallel with the operating contact 13-1 of the time-limited relay 13,
By connecting to the auxiliary relay 7, overcurrent protection after startup, that is, during operation, can be performed using the operating characteristics of the original long-time relay.
O and the operating characteristics 14 of the additionally installed short-time relay can be detected early and the trip wire 2-1 of the circuit breaker 2 can be activated.
By energizing the motor 3, the main circuit power supply is cut off and the motor 3 is stopped, with minimal accident damage.

〔発明の効果〕〔Effect of the invention〕

本発明によれば被保護機器の電動機の起動特性及び許容
熱特性に合致した最適な保護装置を提供することができ
る。According to the present invention, it is possible to provide an optimal protection device that matches the starting characteristics and allowable thermal characteristics of a motor of a protected device.

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

第１図は従来の回路図、第２図は第１図の制御回路図、
第３図は従来の動作時限協調図、第４図は本発明の一実
施例の回路図、第５図は第４図の制御回路図、第６図は
本発明の動作時限協調図である。 １・・・電源、２・・・回路遮断器、３・・・電動機、
４・・・変流器、５・・・長時限動作形過電流継電器、
１１・・・補助変流器、１２・・・短時限動作形過電流
継電器。 代理人　弁理士　高橋明夫 第　１　口 第　３　目 ｂ ＄４　閃 ＄　６″　目 に 茅　２　目 −一一計ｔFigure 1 is a conventional circuit diagram, Figure 2 is a control circuit diagram of Figure 1,
FIG. 3 is a conventional operation time coordination diagram, FIG. 4 is a circuit diagram of an embodiment of the present invention, FIG. 5 is a control circuit diagram of FIG. 4, and FIG. 6 is an operation time coordination diagram of the present invention. . 1...Power supply, 2...Circuit breaker, 3...Electric motor,
4...Current transformer, 5...Long time operation type overcurrent relay,
11...Auxiliary current transformer, 12...Short-time operation type overcurrent relay. Agent Patent Attorney Akio Takahashi No. 1 No. 3 b $4 Flash $6″ Eyes 2-11 total t

Claims (1)

【特許請求の範囲】 １、電動機用電源回路に接続された変流器と・その変流
器の二次回路に接続された過電流保護継電器と、その過
電流保護継電器の動作で前記電動機用電源回路を遮断し
停止させる遮断器とから構成される過電流保護継電装置
において、 補助変流器と、短時限動作形過電流継電器と。 前記電動機の起動時のみ動作する起動判定用遅延継電器
とによって、起動時間の非常に長い電動機に対し、起動
時のみ動作を遅らせ、運転中は当初の動作時間で動作さ
せる手段を設けたことを特徴とする過電流保護継電装置
。[Scope of Claims] 1. A current transformer connected to a power supply circuit for the motor; and an overcurrent protection relay connected to the secondary circuit of the current transformer; and an overcurrent protection relay connected to a secondary circuit of the current transformer; An overcurrent protection relay device consisting of a circuit breaker that cuts off and stops the power supply circuit, an auxiliary current transformer, and a short-time operating type overcurrent relay. The present invention is characterized by providing a means for delaying the operation of a motor with a very long start-up time only at the time of start-up, and operating at the initial operating time during operation, by using a delay relay for start-up determination that operates only when the motor is started. Overcurrent protection relay device.