Non-standard anti-static measures
1. No anti-static product testing equipment
A common mistake is that many companies have purchased a lot of anti-static products, but they have not purchased some commonly used anti-static product testing instruments. We know that each product has a certain period of use, and the quality is good or bad. Without some commonly used testing equipment, we don't know whether the product is damaged or the quality is good. In this way, there is no anti-static effect.
2. Poor ground connection
a. The anti-static system must have an independent and reliable grounding device, the grounding resistance should generally be less than 10Ω, and the burying and testing methods should meet the requirements of GBJ97.
b. The anti-static ground wire must not be connected to the neutral wire of the power supply or shared with the lightning protection ground wire. Because lightning strikes and other phenomena will affect product performance and personal safety through the loop.
c. Use a three-phase five-wire system for power supply, and its earth wire can be used as an anti-static ground wire (but the neutral wire and the ground wire must not be mixed).
d. The cross-sectional area of the grounding trunk line should be no less than 100mm2; the cross-sectional area of the branch trunk line should be no less than 6mm2; the grounding wire of the equipment and workbench should be a multi-stranded plastic-coated wire with a cross-sectional area of 1.25mm2, and the color of the grounding wire should be yellow-green Appropriate.
e. The connection method of the grounding trunk line should be brazed.
f. The connecting terminals of the anti-static equipment should ensure reliable contact, easy to assemble and disassemble, and allow the use of various clip-type connectors, such as snap fish clips, plug sockets, etc.
g. Workplaces with high grounding resistance requirements should install grounding system monitoring and alarm devices, such as the SL-038A grounding system monitoring and alarming device produced by our company, which can monitor whether the ground wire is in good contact with the earth at any time.
3. Use anti-static products as ordinary products
Many companies regard anti-static products as ordinary products, thinking that the products can be used without deformation or breakage. In fact, this is a misunderstanding. For example, an anti-static wrist strap can only be used for a few months. After a period of use, the appearance may not be damaged. However, it is often found that the wrist strap is broken during testing.
4. Not paying attention to socks and insoles
Usually people wear socks or insoles when they wear anti-static shoes. People who are prone to sweating will also conduct static electricity because of these socks and insoles. However, if people who are not prone to sweating on their feet wear some non-anti-static shoes With insoles, the socks and insoles cannot conduct static electricity, so that the static electricity of the human body cannot be introduced into the earth through the shoes. Therefore, place a "human body comprehensive resistance tester" at the entrance of the computer room or factory building, such as the SL-033 human body comprehensive tester produced by our company, which can quickly and accurately detect those who wear unqualified anti-static shoes, socks and insoles . Workers are advised to wear anti-static slippers in the summer and not to wear zizi. In winter, they can wear cotton socks but not nylon socks.
5. Wear only anti-static shoes and not anti-static clothes
In addition to wearing anti-static shoes, people also need to wear anti-static work clothes to better control the static electricity of the human body. Because clothing can also carry very high static electricity, especially now that most clothing is made of chemical fiber, it can generate thousands of tens of thousands of volts of static electricity.
Anti-static coat
6. Wear only anti-static clothes and not anti-static shoes
Experiments have shown that people only wear anti-static work clothes, such as not wearing anti-static shoes and no good anti-static floor, the anti-static effect is extremely poor.
Anti-static men's sandals
7. Anti-static clothes and shoes are worn, but there is no anti-static floor and no anti-static wrist strap
We know that the static electricity of the human body is usually led into the anti-static floor through anti-static shoes, or into the ground through the wrist strap. If there is no anti-static floor and anti-static wrist strap, it is difficult to conduct the static electricity of the person. Qualified companies must have anti-static flooring and anti-static wrist straps, and companies that do not have conditions must have anti-static wrist straps.
Anti-static coated yarn wrist strap
8. Incorrect use of the wrist strap
The wrist strap is easy to damage, so it needs to be checked every day. A good wrist strap will not conduct electricity because the worker wears it too loosely, so the best way is to monitor it at any time with the wrist strap online monitor. However, many companies don't even have a wrist strap tester. If a wrist strap has been used for more than a year, it will not be used until it is broken. This will not have the effect of discharging static electricity.
Anti-static wrist strap
9. Use a cordless wrist strap to prevent static electricity
The theory of the cordless wristband is to use the principle of corona discharge to dissipate part of the static electricity. After the conductor itself is charged, the voltage usually needs to exceed 1500V, and it discharges to the air to dissipate static electricity, but when the cordless wristband dissipates static electricity The required electrostatic voltage is too high to be suitable for the electronics industry, because there are not many electronic components that can withstand high voltages above 1500V. Therefore, we do not recommend the use of wireless wristbands.