Performance advantages: VTM Tube,Tube VTM,VTM Tube Price,VTM Test,VTM Test Tube,Lab Test Tube,Small Test Tube,VTM Sampling Tube Yong Yue Medical Technology(Kunshan) Co.,Ltd , https://www.yonyue.com
Established in 2005, Dongguan Yinyin specializes in a wide range of high-quality electrical components such as silver contacts, electrical contacts, double composite silver nails, riveted and soldered silver contacts, precision stampings, conductive copper posts, contact screws, electrical screws, DC and AC pins, copper sleeves (including hollow needles, semi-hollow needles, four guides), rivets, silver dots, binding posts, AV copper sleeves, 3F07 and 3F05 copper sleeves, 215 copper sleeves, and more. The company also produces various products made from materials like silver, copper, iron, aluminum, and non-magnetic steel. For inquiries, please contact Mr. Chen at 13728192869.
We are a professional manufacturer focused on safety electricity, safe switches, and safe electricians. Our commitment is to provide the most reliable and comprehensive power solutions. Thank you for your attention and support!
**1. Contact Protection**
When inductive loads such as motors, transformers, clutches, or solenoids are turned off, high voltage can be induced across the contacts, which may significantly reduce their lifespan. Additionally, even small currents below 1A can cause arcing, leading to carbonization and oxidation of the contact surfaces, resulting in poor conductivity. This reverse voltage is caused by the energy stored in the inductor, calculated as ½Li², and is expressed as V = -L(di/dt). Under normal conditions, air breaks down at around 200–300V. If the counter-voltage is kept below this threshold, breakdown won’t occur. Implementing a protection circuit, such as the one shown in Figure 57, is highly effective in practical applications.
Common methods include using RC circuits, diodes, or variable resistors. However, adding a protection circuit may increase the release time of the relay. Users should ensure that the protection components are correctly selected and that the load is placed close to the contact side.
**2. Load Type and Inrush Current**
The type of load and its inrush current characteristics play a significant role in determining the switching frequency, which can lead to contact welding. Proper relay selection must consider these factors, including the margin of current capacity under different load conditions. Understanding the relationship between current waveform and time is essential for optimal performance.
**3. Contact Transfer**
Contact transfer occurs when one contact evaporates and deposits onto the other during DC load switching, causing one surface to become concave and the other convex. This phenomenon is more severe with frequent switching, especially when dealing with DC inductive loads, which can generate surges of 2–10A, leading to arcing and sparking. Using appropriate contact materials like AgW or AgCu, along with proper protection circuits, can help minimize this issue.
**4. High-Frequency DC Loads and Electrical Corrosion**
High-frequency DC loads, such as those found in DC tubes and clutches, can cause abnormal electrical corrosion. When contacts open and close, they emit a blue light, which reacts with nitrogen and water vapor in the air, reducing the effectiveness of spark suppression and increasing contact damage. This must be carefully considered by users.
**5. AC vs. DC Switching**
It's generally easier to break an AC circuit than a DC one. AC has zero-crossing points where the current naturally drops to zero, minimizing arc generation and reducing contact wear. Therefore, for the same load, AC is more favorable than DC in terms of contact longevity.
**6. Correct Wiring of Switch Contacts**
To avoid high voltage between contacts, the load should be connected to the power supply side. This prevents dangerous voltage differences and potential short circuits.
**7. Circuits to Avoid**
- Short-circuiting contacts
- Motor forward and reverse circuits, which can cause arcing and damage
- Alternating switching of different voltages, which may result in contact burns and short circuits
- Load sharing between two circuits, which may cause excessive current through the lower contact
**8. Leakage Resistance**
In low-current circuits (dry circuits), contact resistance can be problematic. To improve reliability, a leakage resistor is often added in parallel with the load, ensuring better contact performance at 0.1V and 0.1mA. Double-sub-contact relays are commonly used in such cases, and contact material selection is critical.
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Http://news.chinawj.com.cn Submission.
1.Strong water absorption capacity
2.Increase the collection and release of samples
3.Good abrasion resistance
4.Do not scratch the wiped device
5.No chip drop
6.100% sterilization and disinfection
Operating Steps:
1 Touch the swab to the surface where it is aimed to obtain the sample.
2 Remove the tube cap and put the swab into the transport medium.
3 Break the shaft of the swab so that it will fit in the tube.
4 Close the cap securely.Write on the tube the necessary information about the patient and sample.
Dongguan Yinyin Hardware Products Co., Ltd. is a comprehensive one-stop enterprise that combines production, service, sales, and after-sales support. We welcome all buyers to contact us for negotiations and cooperation!