Product Description
Electric drive and automation training device / Variable Frequency Speed Drive Training System
The power automation and relay protection experimental device is a combination of the current teaching in multiple professional courses such as “Relay Protection”, “Electrical Equipment”, “Automatic Device”, “Factory Power Supply”, “Power System Microcomputer Protection” and other professional courses in colleges and universities. Content, combined with the actual application and development of production, design and develop a novel experimental device. It can conduct operation experiments on relay protection, electrical secondary control circuits and automatic devices commonly used in power plants, substations and factories, and can train students in professional skills in the form of real and intuitive experimental teaching. The advantages of this device are high utilization of equipment components, strong experimental teaching system, less experimental site occupation, and high cost performance. The device adopts a pendant structure, which can be combined according to the experiment content, and is easy to install and use. The experimental instrument has high precision, with functions such as digitization, intelligence and man-machine dialogue. Users can choose according to their needs. The device adopts reliable protection for the power supply, instruments and meters involved in the control panel and measurement components, and a reliable personal safety protection system is also set up to avoid damage to the experimental system and personal injury caused by the misoperation of the students in the experiment .
2. Features
1. Strong comprehensiveness integrates the experimental projects of “Power Automation” and “Relay Protection” courses in various domestic colleges and universities.
2. Strong adaptability can meet the experimental teaching requirements of various colleges and universities “Power Automation” and “Relay Protection” related courses, the depth and breadth of the experiment can be flexibly adjusted according to actual needs. The device adopts a modular hanging box structure, which is convenient to replace. If you need to expand the function or develop a new experiment, you only need to add parts, and it will never be eliminated.
3. The complete set is strong. The device is fully equipped from instruments, special power supplies, relays and other experimental components to experimental connection special wires. The performance and specifications of the provided components can meet the needs of the experiment.
4. Strong intuitiveness Each experimental pendant adopts a separate structure, the component panel is schematic, the diagram line is clear, the task of each pendant is clear, and the operation and maintenance are convenient.
5. The scientific device occupies less area, saves the experimental room and reduces the capital investment; the supporting relays and equipment adopt the field equipment actually used in the power system automation and relay protection device, which has strong authenticity and All are specially designed. The appearance of the device is neat and beautiful, which can improve the experimental environment; the content of power automation and relay protection experiments is rich, and the design is reasonable. In addition to deepening theoretical knowledge, it is also for students to go to society and engage in power supply and distribution work for power plants, substations, and industrial and mining enterprises. , Lay a good foundation for the design, installation, debugging and maintenance of the relay protection system. The measuring instrument adopts a combination of digital, intelligent and man-machine dialogue, which can meet the needs of experimental teaching and realize the modernization of the measurement means of the device; it is equipped with a timer alarm recorder (service manager) for the assessment of students’ experimental skills Provides a unified standard.
6. Strong openness is equipped with internal and external voltage leakage protection devices to ensure the safety of the operator; each power output has functions such as monitoring and short-circuit protection, which is convenient to use; each measuring instrument has a protection function. The whole set of equipment has been carefully designed, coupled with reliable component quality and reliable technology as a guarantee, the product performance is excellent. All these functions create conditions for open experiments and help improve students’ ability to analyze and solve problems.
3. Technical performance
1. Input power: three-phase five-wire 380V±10% 50Hz
2. Working environment: temperature -10ºC~+40ºC relative humidity<85%(25ºC) altitude<4000m
3. Device capacity: <1.5kVA
4. Dimensions: 180cm×73cm×166cm
4. Equipment and requirements
This device organically combines the AC power supply, high-voltage DC power supply, AC measuring instrument, DC measuring instrument, electronic stopwatch, various specifications of load resistance and various specifications of relays required for the experiment, and is complete. Users do not need to purchase any supporting equipment to complete all experiments.
This device is composed of control panel, experiment table and experiment components. Different experiment contents can be completed by using different combinations of pendants.
5. Experimental project
1. Electromagnetic current relay and voltage relay experiment
2. Electromagnetic time relay experiment
3. Signal relay experiment
4. DZ, DZB, DZS series intermediate relay experiment
5.6~10kV line overcurrent protection experiment
6. Low voltage start over current protection and overload protection experiment
7. BFY-12A transistor negative sequence voltage relay experiment
8. Compound voltage start over current protection experiment
9. Impact relay experiment
10. Repeated action to manually reset the central signal device experiment
11. Repeated action automatic return to the central sound signal device experiment
12. Circuit breaker control loop experiment with light monitoring
13. Circuit breaker control loop experiment with light and sound monitoring
14. Experiment of flash device composed of flash relay
15. Circuit breaker control circuit experiment with jumping blocking relay
16. Current blocking voltage quick-break protection experiment
17. DH-3 type three-phase one-time reclosing device experiment
18.BCH-2 differential relay characteristic experiment
19. Comprehensive experiment of overcurrent protection and three-phase automatic reclosing device
Design experiment
—Students design their own circuits according to the experiment topics, make their own wiring according to their own steps, and complete the student’s experimental assessment
20. Low voltage start over current protection and automatic reclosing (post acceleration) comprehensive experiment and assessment
21.Comprehensive experiment and assessment of overcurrent protection and automatic reclosing (post-acceleration) starting with compound voltage
22. Comprehensive experiment and assessment of current blocking voltage quick-break protection and automatic reclosing (post-acceleration)
23. Comprehensive experiment and assessment of overvoltage protection and automatic reclosing (post-acceleration)
24. Three-stage current protection and automatic reclosing (post-acceleration) comprehensive experiment and assessment
25. Comprehensive experiment and assessment of overcurrent protection and automatic reclosing (pre-acceleration)
26. Low voltage start over current protection and automatic reclosing (pre-acceleration) comprehensive experiment and assessment
27.Comprehensive experiment and assessment of overcurrent protection and automatic reclosing (pre-acceleration) initiated by compound voltage
28. Comprehensive experiment and assessment of current blocking voltage quick-break protection and automatic reclosing (pre-acceleration)
29. Comprehensive experiment and assessment of overvoltage protection and automatic reclosing (pre-acceleration)
30. Three-stage current protection and automatic reclosing (front acceleration) comprehensive experiment and assessment
6. Device safety protection system
1. Three-phase five-wire system power input, the total power is controlled by a three-phase key switch, with a fuse.
2. The power supply of the control panel is controlled by the contactor through the start and stop buttons.
3. The screen is equipped with 2 sets of voltage-type leakage protection devices and a set of current-type leakage protection devices. If there is leakage inside or outside the control screen or strong current output, it will alarm and cut off the main power supply to ensure the safety of the experiment.
4. There is an overcurrent protection device at the output of single and three-phase voltage regulators, which can automatically protect the phase-to-phase, line-to-line overcurrent or direct short circuit.
5. Equipped with a timer and alarm recorder (service manager) to record the number of illegal use, and provide a unified standard for the assessment of students’ experimental skills.
6. Various power supplies and various instruments have perfect protection functions.
7. Configuration checklist
| Number | Model | Specification | Unit | QTY |
| 1 | Power control panel | set | 1 | |
| 2 | Experiment table | set | 1 | |
| 3 | DL01 | Circuit breaker contact and control circuit simulation box | pcs | 1 |
| 4 | DL02 | Signal indication and universal switch box | pcs | 1 |
| 5 | DL03 | Digital stopwatch hanging box | pcs | 1 |
| 6 | DL04 | Air switch hanging box | pcs | 1 |
| 7 | DL05 | Light brand hanging box (1) | pcs | 1 |
| 8 | DL06 | Light brand hanging box (2) | pcs | 1 |
| 9 | DL07 | Relay hanging box (1) | pcs | 1 |
| 10 | DL08 | Relay hanging box (2) | pcs | 1 |
| 11 | DL09 | Relay hanging box (3) | pcs | 1 |
| 12 | DL10 | Relay hanging box (4) | pcs | 1 |
| 13 | DL11 | Relay hanging box (5) | pcs | 1 |
| 14 | DL12 | Relay hanging box (6) | pcs | 1 |
| 15 | DL13 | Relay hanging box (7) | pcs | 1 |
| 16 | DL14 | Relay hanging box (8) | pcs | 1 |
| 17 | DL15 | Reclosing relay and control parts hanging box | pcs | 1 |
| 18 | DL16 | Differential relay hanging box | pcs | 1 |
| 19 | DL17 | DC digital voltage and ammeter hanging box (three meters) | pcs | 1 |
| 20 | DL18 | AC ammeter hanging box (three meters) | pcs | 1 |
| 21 | DL19 | AC voltmeter hanging box | pcs | 1 |
| 22 | DL20 | Adjustable resistance hanging box (1) | pcs | 1 |
| 23 | DL21 | Adjustable resistance hanging box (2) | pcs | 1 |
| 24 | DL22 | Adjustable resistance hanging box (3) | pcs | 1 |
| 25 | DL23 | Adjustable resistance hanging box (4) | pcs | 1 |
| 26 | Safety superposition type experimental lead, 1m lead: (red 10, green 10, yellow 10, black 10), 30mm lead: (red 10, yellow 10, black 10) | set | 1 | |
| 27 | Student stool | pcs | 2 |
Types of Screw Shafts
Screw shafts come in various types and sizes. These types include fully threaded, Lead, and Acme screws. Let’s explore these types in more detail. What type of screw shaft do you need? Which 1 is the best choice for your project? Here are some tips to choose the right screw:
Machined screw shaft
The screw shaft is a basic piece of machinery, but it can be further customized depending on the needs of the customer. Its features include high-precision threads and ridges. Machined screw shafts are generally manufactured using high-precision CNC machines or lathes. The types of screw shafts available vary in shape, size, and material. Different materials are suitable for different applications. This article will provide you with some examples of different types of screw shafts.
Ball screws are used for a variety of applications, including mounting machines, liquid crystal devices, measuring devices, and food and medical equipment. Various shapes are available, including miniature ball screws and nut brackets. They are also available without keyway. These components form a high-accuracy feed mechanism. Machined screw shafts are also available with various types of threaded ends for ease of assembly. The screw shaft is an integral part of linear motion systems.
When you need a machined screw shaft, you need to know the size of the threads. For smaller machine screws, you will need a mating part. For smaller screw sizes, the numbers will be denominated as industry Numeric Sizes. These denominations are not metric, but rather in mm, and they may not have a threads-per-inch designation. Similarly, larger machine screws will usually have threads that have a higher pitch than those with a lower pitch.
Another important feature of machine screws is that they have a thread on the entire shaft, unlike their normal counterparts. These machine screws have finer threads and are intended to be screwed into existing tapped holes using a nut. This means that these screws are generally stronger than other fasteners. They are usually used to hold together electronic components, industrial equipment, and engines. In addition to this, machine screws are usually made of a variety of materials.
Acme screw
An Acme screw is the most common type of threaded shaft available. It is available in a variety of materials including stainless steel and carbon steel. In many applications, it is used for large plates in crushing processes. ACME screws are self-locking and are ideal for applications requiring high clamping force and low friction. They also feature a variety of standard thread forms, including knurling and rolled worms.
Acme screws are available in a wide range of sizes, from 1/8″ to 6″. The diameter is measured from the outside of the screw to the bottom of the thread. The pitch is equal to the lead in a single start screw. The lead is equal to the pitch plus the number of starts. A screw of either type has a standard pitch and a lead. Acme screws are manufactured to be accurate and durable. They are also widely available in a wide range of materials and can be customized to fit your needs.
Another type of Acme screw is the ball screw. These have no back drive and are widely used in many applications. Aside from being lightweight, they are also able to move at faster speeds. A ball screw is similar to an Acme screw, but has a different shape. A ball screw is usually longer than an Acme screw. The ball screw is used for applications that require high linear speeds. An Acme screw is a common choice for many industries.
There are many factors that affect the speed and resolution of linear motion systems. For example, the nut position and the distance the screw travels can all affect the resolution. The total length of travel, the speed, and the duty cycle are all important. The lead size will affect the maximum linear speed and force output. If the screw is long, the greater the lead size, the higher the resolution. If the lead length is short, this may not be the most efficient option.
Lead screw
A lead screw is a threaded mechanical device. A lead screw consists of a cylindrical shaft, which includes a shallow thread portion and a tightly wound spring wire. This spring wire forms smooth, hard-spaced thread convolutions and provides wear-resistant engagement with the nut member. The wire’s leading and trailing ends are anchored to the shaft by means appropriate to the shaft’s composition. The screw is preferably made of stainless steel.
When selecting a lead screw, 1 should first determine its critical speed. The critical speed is the maximum rotations per minute based on the natural frequency of the screw. Excessive backlash will damage the lead screw. The maximum number of revolutions per minute depends on the screw’s minor diameter, length, assembly alignment, and end fixity. Ideally, the critical speed is 80% of its evaluated critical speed. A critical speed is not exceeded because excessive backlash would damage the lead screw and may be detrimental to the screw’s performance.
The PV curve defines the safe operating limits of a lead screw. This relationship describes the inverse relationship between contact surface pressure and sliding velocity. As the PV value increases, a lower rotation speed is required for heavier axial loads. Moreover, PV is affected by material and lubrication conditions. Besides, end fixity, which refers to the way the lead screw is supported, also affects its critical speed. Fixed-fixed and free end fixity are both possible.
Lead screws are widely used in industries and everyday appliances. In fact, they are used in robotics, lifting equipment, and industrial machinery. High-precision lead screws are widely used in the fields of engraving, fluid handling, data storage, and rapid prototyping. Moreover, they are also used in 3D printing and rapid prototyping. Lastly, lead screws are used in a wide range of applications, from measuring to assembly.
Fully threaded screw
A fully threaded screw shaft can be found in many applications. Threading is an important feature of screw systems and components. Screws with threaded shafts are often used to fix pieces of machinery together. Having fully threaded screw shafts ensures that screws can be installed without removing the nut or shaft. There are 2 major types of screw threads: coarse and fine. When it comes to coarse threads, UTS is the most common type, followed by BSP.
In the 1840s, a British engineer named Joseph Whitworth created a design that was widely used for screw threads. This design later became the British Standard Whitworth. This standard was used for screw threads in the United States during the 1840s and 1860s. But as screw threads evolved and international standards were established, this system remained largely unaltered. A new design proposed in 1864 by William Sellers improved upon Whitworth’s screw threads and simplified the pitch and surface finish.
Another reason for using fully threaded screws is their ability to reduce heat. When screw shafts are partially threaded, the bone grows up to the screw shaft and causes the cavity to be too narrow to remove it. Consequently, the screw is not capable of backing out. Therefore, fully threaded screws are the preferred choice for inter-fragmentary compression in children’s fractures. However, surgeons should know the potential complication when removing metalwork.
The full thread depth of a fully threaded screw is the distance at which a male thread can freely thread into the shaft. This dimension is typically 1 millimeter shy of the total depth of the drilled hole. This provides space for tap lead and chips. The full-thread depth also makes fully threaded screws ideal for axially-loaded connections. It is also suitable for retrofitting applications. For example, fully threaded screws are commonly used to connect 2 elements.
Ball screw
The basic static load rating of a ball screw is determined by the product of the maximum axial static load and the safety factor “s0”. This factor is determined by past experience in similar applications and should be selected according to the design requirements of the application. The basic static load rating is a good guideline for selecting a ball screw. There are several advantages to using a ball screw for a particular application. The following are some of the most common factors to consider when selecting a ball screw.
The critical speed limit of a ball screw is dependent on several factors. First of all, the critical speed depends on the mass, length and diameter of the shaft. Second, the deflection of the shaft and the type of end bearings determine the critical speed. Finally, the unsupported length is determined by the distance between the ball nut and end screw, which is also the distance between bearings. Generally, a ball screw with a diameter greater than 1.2 mm has a critical speed limit of 200 rpm.
The first step in manufacturing a high-quality ball screw is the choice of the right steel. While the steel used for manufacturing a ball screw has many advantages, its inherent quality is often compromised by microscopic inclusions. These microscopic inclusions may eventually lead to crack propagation, surface fatigue, and other problems. Fortunately, the technology used in steel production has advanced, making it possible to reduce the inclusion size to a minimum. However, higher-quality steels can be expensive. The best material for a ball screw is vacuum-degassed pure alloy steel.
The lead of a ball screw shaft is also an important factor to consider. The lead is the linear distance between the ball and the screw shaft. The lead can increase the amount of space between the balls and the screws. In turn, the lead increases the speed of a screw. If the lead of a ball screw is increased, it may increase its accuracy. If not, the lead of a ball screw can be improved through preloading, lubrication, and better mounting accuracy.
