- Shangchai generator set
- Cummins generator set
- Yuchai generator set
- Weifang Diesel Generator
- Gasoline generator
- Single-cylinder diesel engine
Contact Songge Mechanical
Cummins generator set-Yuchai generator set-Silent diesel generator-Guangzhou Songge Mechanical and Electrical Co., Ltd.
020-84851836 Consulting Hotline: 020-84851836
曹先生 Contact: Mr. Cao
13609022338 Mobile: 13609022338
020-34865288 Fax: 020-34865288
firstname.lastname@example.org Email: email@example.com
广东省广州市沙湾镇大涌口第二工业区1号 Address: No. 1 Second Industrial Zone, Dayongkou, Shawan Town, Guangzhou City, Guangdong Province
Common protection knowledge of generator motors
Internal information, generator motors, we should pay attention to the following points in daily use:
1. Why are electric motors easier to burn than in the past?
Due to the continuous development of insulation technology, it is required to increase the output and reduce the volume in the design of the motor, so that the thermal capacity of the new motor is getting smaller and smaller, and the overload capacity is getting weaker. Motors often run in a variety of ways, such as frequent starting, braking, forward and reverse, and variable load, which place higher requirements on motor protection devices. In addition, the application area of the motor is more widely used in extremely harsh environments, such as humid, high temperature, dusty, and corrosive occasions. Coupled with the non-standard construction of motors, and omissions in equipment management. All of this makes the current motor more easily damaged than in the past.
2. Why is the protection effect of traditional protection devices not ideal?
Traditional motor protection devices are mainly fuses and thermal relays.
Fuse is the earliest and simplest protection device. In fact, fuses are mainly used to protect power supply lines during short-circuit faults and reduce the expansion of fault scope. It is unscientific to think that the fuse can protect the motor from short circuit or overload. It is not scientific to select the fuse according to the motor's starting current, but to select it based on the rated current. Didn't you know that this will more easily cause the motor to damage the motor due to phase loss operation.
Thermal relay is the most widely used motor overload protection device. However, the thermal relay has a single function, low sensitivity, large error, and poor stability. It has been recognized by the majority of electrical workers. All these defects cause unreliable motor protection. This is exactly the case; despite the fact that many devices are equipped with thermal relays, damage to motors that affects normal production is still common.
3． Protector selection principle?
The purpose of selecting the motor protection device can not only make the motor fully exert its overload capacity, but also avoid damage, and also improve the reliability and production continuity of the electric drive system. When selecting a protective device at the same time, several contradictory factors must be considered, namely reliability, economy, simple structure, easy operation and maintenance. When the protection requirements can be met, the simplest protection device is considered first. Only when the simple protection device fails to meet the requirements, or when higher protection characteristics are required, the application of a complex protection device is considered.
4. Ideal motor protector?
The ideal motor protector is not the most versatile or the most advanced, but it should be the most practical.
So what is practical? Practicality should meet the factors of reliability, economy, convenience, etc., and have a high performance-price ratio.
So what is reliable? Reliability should first meet the reliability of the function. For example, the overcurrent and phase failure functions must be able to reliably operate in various situations, various processes, and overcurrents and phase failures that occur in various ways. Secondly, its own reliability (since the protector protects others, especially with high reliability) must have adaptive stability and durability to various harsh environments.
Economical: Adopt advanced design, reasonable structure, professional and large-scale production, reduce product cost, and bring high economic benefits to users.
Convenience: It must be at least similar to a thermal relay in terms of installation, use, adjustment, wiring, etc., as simple and convenient as possible.
Because of this, relevant experts have already predicted that in order to simplify the electronic motor protection device, a design scheme without a power supply transformer (passive) should be designed and replaced with a semiconductor (such as a thyristor) to perform electromagnetic operations with contacts. element. In this way, it is possible to manufacture a protective device consisting of a minimum number of components.
We know that active power will bring unreliability. One normally needs working power, and the other will lose working power when phase is broken. This is a contradiction that cannot be overcome at all. In addition, it needs to be powered for a long time, which is susceptible to the impact of grid voltage fluctuations and large current shocks. Its own failure rate will be greatly increased. At the same time, the volume and cost will be increased. Therefore, the motor protection industry takes active and passive as a milestone in technological progress. As a user, you should also consider passive products first when choosing.
5. What are the characteristics of Julong UL series protectors?
The UL series protectors have the protection function of symmetrical faults (such as overload, stall, overvoltage, undervoltage, etc.) and asymmetrical faults (such as phase failure, current imbalance, phase-to-phase short circuit, and inter-turn short circuit, etc.) The use of contactors can quickly and reliably protect any type of three-phase motor.
The protector adopts current detection technology, no external power supply is needed, and the output interface adopts the design scheme of intelligent zero-crossing shut-off AC solid-state relay. The entire series adopts a core-piercing, fully enclosed structure. The protector has the advantages of simple structure, reliable operation, convenient use, low price, no power consumption, no spark, no maintenance, long life and small size. It is currently the only electronic motor protector in China that can truly replace thermal relays. It is especially suitable for occasions where the working environment is poor and the quality of the power grid is poor, and it has an immediate effect.
6 · Why is the "julong" protector the first choice brand in China?
As Julong permeates the concept of "customer first" to every employee and implements every link of scientific research, manufacturing, and service, the products launched are truly high-quality and cheap, and our services reflect sincerity and integrity everywhere. .
High quality: It has three leading international technologies: passive, core-piercing, and intelligent.
It has six outstanding advantages of being proud of its peers: perfect protection function, ideal protection characteristic, intuitive indication function, concise wiring, accurate setting, and simple installation.
Inexpensive: The professional and large-scale production makes the Dragon Protector have an unbeatable performance-price ratio.
Advanced design, reasonable structure, exquisite workmanship, and work attitude of excellence, ensure the high reliability of the product, and dare to promise to the society: free trial, unconditional return, and lifetime warranty system.