CN2150647Y

CN2150647Y - Magnetic-starter for transient fault delay interruption of power system

Info

Publication number: CN2150647Y
Application number: CN 93230298
Authority: CN
Inventors: 谷恩荣
Original assignee: Individual
Current assignee: Individual
Priority date: 1993-03-01
Filing date: 1993-03-01
Publication date: 1993-12-22
Anticipated expiration: 2003-03-01

Abstract

The utility model relates to a magnetic-starter for transient fault delay interruption of a power system. An air type time relay which can delay time during the power supply is cut is added in an existing magnetic-starter; the coil of the relay is connected in parallel with the coil of a contactor; after the time delay switching-off contacts of the relay are connected in series with a toggle switch, the time delay switching-off contacts of the relay are connected in parallel with the two ends of the auxiliary normally-open self-locking contact of the contactor. When the power supply is transitorily cut, because the time delay switching-off contacts of the time relay are still in closed state, a control circuit is still in closed state, and the uninterrupted running of motors or other electrical equipment is ensured thereby.

Description

Magnetic-starter for transient fault delay interruption of power system

The utility model relates to the remote three-phase AC asynchronous motor starting of a kind of direct control, stops the starter of usefulness, especially a kind of magnetic starter that has the open circuit of delaying time when the power supply instantaneous power failure, guarantee the continuous running of motor.

At present, various magnetic starters generally all are made up of A.C. contactor, thermal relay and metal shell, all have the o-volt protection performance and the overload of motor is shielded, but do not have the performance of time-delay open circuit when the power supply instantaneous power failure.Like this, when electric power system high-tension line generation transient fault, the high-voltage switch gear of the automatic tripping faulty line of protective relaying device, the high-voltage line outage, fault generally can be eliminated automatically, the auto recloser action, high-voltage switch gear is overlapped, high-tension line restores electricity, be generally 1.2-2.5 to the time that restores electricity (it comprises relaying protection 0.5-1.0 operate time second second from transient fault takes place, high-voltage switch gear opening time 0.06 second, 0.5 second operate time of reclosing, high-voltage switch gear closing time 0.2-0.3 second); The high voltage bus that automatic switching device of standby power supply is arranged, a power circuit fault, another power circuit drops into automatically, and the time that restores electricity from breaking down to is generally 0.7-1.8 second.Owing to have only a few tens of milliseconds the release time of A.C. contactor; so under above-mentioned failure condition; by the fault high-tension line and be subjected to fault effects voltage to reduce the user of more non-fault high-tension line power supply; their all are by motor and other electric equipments of contactor or magnetic starter control; all, contactor causes shutdown because of discharging automatically; when personnel on duty find; follow procedure opens again; be that the time is longer; particularly those unattended and motor and other electric equipments long-term operation, then downtime is longer.Owing to shut down widely, downtime is long, all is very big to the influence of all kinds of production product quantities and quality.

The purpose of this utility model is to overcome above-mentioned the deficiencies in the prior art, and a kind of magnetic starter of the open circuit of can delaying time is provided.

The utility model is achieved in that in metal shell, A.C. contactor KM, thermal relay KH are housed, the air time relay KT that has utilized an outage time-delay dexterously that is characterised in that of the present utility model, the coil of this relay and the coils from parallel connection of coils of contactor, behind toggle switch of time-delay breaking-off contact series connection, be connected in parallel on the auxiliary of contactor and often open self-locking contact two ends, this redlay spring energy storage during energising is delayed time by the orifice restriction principle during outage.

Below in conjunction with accompanying drawing: " time-delay of electric power system transient fault open circuit starter electrical principle winding diagram 1 ", the utility model is elaborated, Q1 is a three-pole knife switch among the figure, and Q2 is a toggle switch, and FU is a fuse, KM is an A.C. contactor, KT is the air time relay of outage time-delay, and SB1 is a stop button, and SB2 is a starting button, KH is a thermal relay, and M is a threephase asynchronous.When switch Q2 is closed, time-delay opening performance input, when Q2 opened, the time-delay opening performance withdrawed from.Behind the Q1 switch that closes, when pressing starting button SB2, contactor KM coil electricity, KM main contact closure, auxiliary self-locking contact KM closure, motor M starting and running continuously; Simultaneously, time relay KT coil electricity, its adhesive moving unshakable in one's determination, spring energy-storage, KT contact moment closure, the Q2 that closes a switch again, time-delay opening performance input.When electric power system generation transient fault caused the high-tension line switch tripping of powering to this motor, power supply had a power failure, and contactor KM is electric because of coil has to be discharged automatically, KM main contact and the disconnection of KM self-marketing contact, and at this moment, motor is turning round by inertia.But the time-delay breaking-off contact KT of the time relay is still in closure state (its time-delay adjust opening time greater than the transient fault interruption duration 1.2-2.5 of system second).When fault disappears, after circuit reclosing successful reclosing or the automatic closing success, restore electricity, because of the wire loop of contactor still in on-state, so contactor adhesive immediately, motor recovers normal operation.So just avoid unnecessary shutdown, significantly reduced user's loss.

When power supply is non-instantaneous power-off, if interruption duration greater than the setting time of time relay KT (be generally 1.2-2.5 second, should not be greater than 3 seconds, the delay time of this relay is 0.4-60 second, in this scope, regulate arbitrarily), time-delay breaking-off contact KT disconnects, and contactor discharges automatically.If power supply is sent a telegram here again, not according to starting button SB2, motor M fail to start is so this utility model still can prevent motor M self-starting under static state.

When orderly closedown, first cut-off switch Q2 presses stop button SB1 again, and contactor discharges shutdown immediately.If do not disconnect the Q2 switch, reaching time relay setting time (1.2-2.5 second) by the stop button time can shut down.

The rated voltage of the A.C. contactor in the utility model, thermal relay and the time relay should be selected for use according to supply voltage.The rated current of contactor and thermal relay should be selected for use according to the rated current more than or equal to motor.For the bigger the utility model of rated current, shouldn't metal shell, as long as above-mentioned electric component reasonable Arrangement on flat board, press above-mentioned schematic diagram wiring again and get final product.

The utility model also can be made into the direct current time-delay starter that opens circuit, as long as select D.C. contactor, DC dump time-delay air time relay for use, gets final product by above-mentioned schematic diagram wiring.

The utility model not only is used to control AC-DC motor, also can be used to control supply line and other electric equipment.

Owing to adopt the utility model when the power supply instantaneous power-off, still can guarantee the continuous operation of motor or circuit and other equipment.Avoided unnecessary shutdown.Extensively adopt the utility model, its social benefit and economic benefit are huge.The utility model only adopts the air time relay of an outage time-delay, be issued to open circuit purpose of time-delay at powering-off state, this relay is not subjected to the restriction of motor or other electric equipment amount of capacity, simple in structure, volume is little, in light weight, time-delay is reliable, delay time is adjusted conveniently, cheap.

Claims

1, a kind of magnetic starter that contactor, thermal relay are housed, it is characterized in that this device is equipped with the air time relay of an outage time-delay, the coil of this relay and the coils from parallel connection of coils of contactor, behind toggle switch of time-delay breaking-off contact series connection, be connected in parallel on the auxiliary self-locking contact two ends of often opening of contactor.