Static eliminator ion is not clean or the cause of failure
Is the ion elimination of the static eliminator not clean or the cause of the failure? The static eliminator is composed of a high-voltage power generator and a discharge electrode (usually made of ion needles). The air is ionized into a large number of positive and negative ions through high-voltage corona discharge, and then a large number of positive and negative ions are blown onto the surface of the object to neutralize it Static electricity, or directly put the static eliminator close to the surface of the object to neutralize static electricity. It is widely used in the electrostatic prevention and control of ESDS (electrostatic discharge sensitive) devices. In daily use, static eliminators will inevitably appear, the ions are not eliminated or the ion elimination is ineffective. Today we will take a look at the causes of these problems.
1. Power and gas source.
① The power supply is not grounded or grounding does not fully guarantee grounding. The transformer did not guarantee a good grounding, and did not check whether the grounding knob was tightened.
②The air source used is not effectively filtered, and the filter is not cleaned in time. The particles that cause water, oil, and dust/dust enter the ion generation chamber and adhere to the inner wall of the plastic part.
Note: When water, oil and dust/dust particles accumulate to a certain extent, the ion needle will ignite them. As a result, the plastic parts gradually form honeycomb coke damage, and the ion rejection is gradually reduced; this will cause safety hazards.
2. Adjust the static elimination effect of the static eliminator.
①The effect of removing static electricity The time of removing static electricity is inversely proportional to the air pressure. The air pressure should be 0.3Mpa-0.7Mpa.
②The distance and angle between the gun head, the nozzle head and the electrostatic field all affect the effect of static electricity, so you should pay attention to debugging until you are satisfied.
Third, the launch needle problem
① Pollution of launch needle
After a high voltage is applied to the emission needle, the tiny dust around the emission needle will be charged with the generated ions. Due to the Coulomb force between the discharge needle and the charged dust, the dust will adhere to the launching needle, causing pollution of the launching needle.
②The launching needle is damaged
The static eliminator usually applies a high voltage of 4kV or more (2-3kV for high frequency AC mode) on the discharge needle. Therefore, the tip of the discharge needle is loaded with a very large energy load. This is the main reason for the wear of the discharge needle, and pollution will increase the corrosion and wear of the electrode needle.
Once the tip of the discharge needle is worn, it will inevitably reduce the concentration of electric field energy, so the amount of ion generation will also decrease. When the amount of ion generation is reduced, the neutralization time becomes slower. In addition, after the discharge needle is worn, it will have a significant impact on the amount of positive and negative ions. That is to say, just like the influence of the discharge needle contamination, the reduction of positive ions is more than that of negative ions, so the generation of negative ions is more than that of positive ions, resulting in poor electrostatic balance.