CN203596769U - Novel Y-delta starting box - Google Patents

Abstract

The utility model discloses a novel Y-△ starter box, which includes a circuit breaker, a fuse, an opening button, a closing button, a time relay, a motor protector, and three sets of AC contactors. The motor protector is an electronic motor integrated As for the protector, the coil of the electronic integrated motor protector is connected in parallel with the coil of the contactor KA, and the normally closed contacts of the electronic integrated motor protector are connected in series in the secondary protection circuit. The utility model replaces the original thermal relay by using the JD5 series motor protector of the integrated mode fully enclosed structure, so as to protect the three-phase AC motor. Three-phase unbalanced protection, fault, and operating characteristic indication functions are integrated, and it has extremely good inverse time-limit characteristics. The utility model is provided with an operation indication, a phase failure indication and an overload alarm, which is convenient for installation and debugging, eye-catching and intuitive, and quick for troubleshooting.

Description

A new type of Y—△ starter box

technical field

The utility model relates to a new Y-△ starter box.

Background technique

In a typical asynchronous motor Y-△ step-down start control start circuit, there are often three sets of AC contactors whose main contacts are connected to the main circuit to connect the motor stator winding power supply, that is, the star-delta start circuit. As shown in Figure 1, the existing star-delta starting circuit includes circuit breaker QF, fuses FU1, FU2, opening button TA, closing button HA, time relay SJ, three sets of AC contactors KY, KA and K△, and Most of the existing motor protectors in the overload and short-circuit protection circuits use thermal relays JR, and the specific wiring is shown in Figure 1, which will not be repeated here. However, in practical applications, when the thermal relay JR is used to protect the motor, the phase failure, overvoltage and overload protection of the thermal relay cannot meet the requirements of protecting the motor, especially after long-term use, its inverse time-limit characteristics are greatly reduced and the action is slow. , low accuracy, poor reliability, easy to cause damage or damage to the motor, the motor protection effect is not good, and the motor cannot be well protected.

Utility model content

The purpose of this utility model is to provide a new type of Y-△ starter box, which has extremely good inverse time limit characteristics, good energy saving, high action sensitivity, high precision, impact and vibration resistance, good repeatability, complete protection functions, and low power consumption. Small.

The utility model adopts the following technical solutions:

A new type of Y-△ starter box, including a circuit breaker, a fuse, an opening button, a closing button, a time relay, a motor protector, and three sets of AC contactors. The motor protector is an electronic comprehensive motor protector. The coil of the electronic comprehensive motor protector is connected in parallel with the coil of the contactor, and the normally closed contacts of the electronic comprehensive motor protector are connected in series in the secondary protection circuit.

The electronic comprehensive motor protector adopts JD5 series motor comprehensive protector.

The utility model has a simple structure. The original thermal relay is replaced by the JD5 series motor protector with an integrated mode fully enclosed structure, so as to protect the three-phase AC motor. The utility model integrates overload, phase loss, internal star-delta phase failure, Blockage and three-phase unbalanced protection, fault, and operating characteristic indication functions are integrated, and have extremely good inverse time-limit characteristics. Moreover, the utility model is equipped with operation indication, phase failure indication and overload alarm, which is convenient for installation and debugging, eye-catching and intuitive, and rapid troubleshooting; it has energy saving, sensitive action, high precision, shock resistance and vibration resistance, good repeatability, and complete protection functions. Low power consumption and other advantages.

Description of drawings

Fig. 1 is the schematic diagram of the existing Y-△ step-down starter circuit;

Fig. 2 is the schematic circuit diagram of the utility model.

Detailed ways

As shown in Figure 2, a new type of Y-△ starter box includes a circuit breaker QF, fuses FU1, FU2, opening button TA, closing button HA, time relay SJ, motor protector, three sets of AC contactors KY, KA and K△, the motor protector is an electronic comprehensive motor protector, the coil of the electronic comprehensive motor protector is connected in parallel with the coil of the contactor KA, and the electronic comprehensive motor protector is usually The closed contacts are connected in series in the secondary protection circuit.

The electronic comprehensive motor protector adopts JD5 series motor comprehensive protector. JD5 series motor integrated protector adopts an integrated mode fully enclosed structure to protect three-phase AC motors. The JD5 series motor comprehensive protector integrates overload, phase loss, internal star-delta phase failure, locked rotor and three-phase unbalanced protection, fault, and operating characteristic indication functions, and has extremely good inverse time-limit characteristics. Protection < 2 seconds, overvoltage 1~40 seconds (relative) and overload 3~80 seconds (relative). However, the existing thermal relays cannot be realized. JD5 series motor integrated protector can also design over-current scale setting, which solves the phenomenon of inaccurate and low-precision setting of over-current rectifiers in many protection devices. The utility model is equipped with operation indication, phase failure indication and overload alarm, and is convenient for installation and debugging, eye-saving and intuitive, rapid troubleshooting, energy-saving, sensitive in action, high in precision, shock-resistant and vibration-resistant, good in repeatability and complete in protection functions. , low power consumption and other advantages.

The utility model adopts the quantitative setting method of the potentiometer, only needs to set the protection overload current according to the rated current value marked on the nameplate of the motor, and can realize accurate static setting without running a test machine.

When the motor starts normally, press the HA closing button, the AC contactor coil KY is energized, and the normally open locking contacts KY1 and KM1 are closed, so that the AC contactor coil KM and the time relay coil SJ are energized and start to delay. When the set time value is reached, the delay opening contact SJ1 is opened, and the delay closing contact SJ2 is closed. At this time, the AC contactor coil KY is de-energized, and the AC contactor coil K△ is energized to complete the Y-△ start conversion. into normal working condition. When the three-phase power supply of the motor has abnormal working conditions such as phase failure, overcurrent, start-up overtime protection , short circuit, unbalanced three-phase current, and stalled rotor, the integrated motor protector JD1 will be energized, the normally closed contact JD2 will be disconnected, and the AC contact When the coil KM of the coil is de-energized, the main circuit of the motor is disconnected, and the motor is quickly and reliably protected.

The comprehensive motor protector adopts the time-delay avoidance technology in the starting process under the current ratio control. When the motor starts within the normal starting current ratio range, the startup avoidance time is valid; when the motor starting current ratio exceeds the normal starting current ratio range or the phase is broken, The start avoidance time is invalid, and the motor will be protected quickly.

Claims (2)

1. novel Y-△ starter box; comprise circuit breaker; fuse; opening button, switch knob, the time relay, motor protecter, three groups of A.C. contactors; it is characterized in that: described motor protecter is electron type comprehensive protector of motor; the described coil of electron type comprehensive protector of motor and the coil of contactor are in parallel, and the normally-closed contact of described electron type comprehensive protector of motor is connected in second protection loop.

2. novel Y-△ starter box according to claim 1, is characterized in that: described electron type comprehensive protector of motor adopts JD5 serial motors comprehensive protection device.

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