The static elimination speed of ion wind snake is an important part of measuring the electrostatic performance of ion wind nozzle. Therefore, when introducing our own products, the speed of static elimination is the main criterion of performance. So how do users choose the right product for them?
The antistatic properties of the ion wind snake include: the speed of static elimination, the amount of residual voltage, and the balance of positive and negative ions. The static elimination speed refers to the time of neutralization, that is, the time taken from the analog to generate 1KV (or 5KV) high voltage to 100V (or 500V), which is generally about 1S to 4.5S; the residual voltage refers to the static electricity after neutralization. The amount of charge remaining has a positive and negative charge, generally around ±15V. The ion balance refers to the equivalent amount of positive and negative charges, which determines the amount of residual voltage in the region.
Understand these technical parameters, when users choose the ion tuyere, you can refer to the following points:
1. Electrostatic control of ion tuyere area: manual work on site, no need to pursue static removal time quickly, but must choose ion ion nozzle with good ion balance, such as within ±10V and long-term stable performance, because it is equivalent to losing safety. In the ESD environment, even if the static electricity speed is slower, it does not matter much.
2. Electrostatic control of ion tuyere area: semi-automatic and semi-manual operation. The operation speed and frequency of the equipment should be considered in this operation site. The static electricity speed should be as fast as possible when selecting. Generally it is suitable for about 2.5 seconds.
Static power supply in the manufacture of electronic products
(1) The activity of the human body, static electricity generated by friction, contact and separation between people and clothes, shoes, socks, etc. is one of the main static power sources in the manufacture of electronic products. Static electricity in the human body is the main cause of hard (soft) breakdown of the device. The electrostatic voltage generated by human activities is about 0.5-2KV. In addition, the air humidity has a great influence on the electrostatic voltage, and if it is in the dry environment, it is increased by one order of magnitude. Table 2 shows the relationship between relative humidity and human body activity.
When the human body is charged and touched to the ground wire, a discharge phenomenon will occur, and the human body will have different degrees of electric shock response. The degree of reaction is called the electric shock sensitivity. Table 3 shows the electric shock sensitivity of the human body during different static voltage discharges.
(2) When the chemical fiber or cotton overalls are rubbed against the work surface and the seat, an electrostatic voltage of 6000V or more can be generated on the surface of the garment, and the human body is charged. When contact with the device, it will cause discharge and easily damage the device.
(3) The insulation resistance of the rubber or plastic sole is as high as 1013 Ω. When it rubs against the ground, it generates static electricity and charges the human body.
(4) When the resin, paint film, and plastic film packaged device are transported in a package, the surface of the device and the packaging material can generate an electrostatic voltage of several hundred volts to discharge the sensitive device.
(5) Various packaging, cartridges, and turnovers made of polymer materials such as PP (polypropylene), PE (polyethylene), PS (polyvinylidene), PVR (polyurethane), PVC, polyester, and resin. Boxes, PCB racks, etc. may generate 1-3.5KV electrostatic voltage due to friction and shock, and discharge sensitive fasteners.
(6) Ordinary work surface, which is electrostatically generated by friction.
(7) The insulation resistance of concrete, waxed polished floor, rubber sheet and other insulating floors is high, and the static charge on the human body is not easy to leak.
(8) Electronic production equipment and tools: High-voltage transformers and AC/blind flow circuits in equipment such as soldering irons, wave soldering machines, reflow soldering furnaces, placement machines, commissioning and inspection devices all induce static electricity in the equipment. If the device is not properly vented, it will cause the sensitive device to fail during the manufacturing process. The hot air circulating in the oven and the box friction, and the CO2 vapor in the CO2 cryostat cooling box can generate a large amount of static charge.