Testing of anti-static shoes
The anti-static shoes are made of PVC or PU foam material, which is made of dissipative materials. It is integrally formed with the upper and then reinforced on the line. It can effectively discharge static electricity and form a complete anti-static system together with anti-static clothing. Anti-static shoes are smart and light. Anti-static EVA is provided in the middle of the sole to relieve the pressure on the foot. It is softer and more comfortable. The overall appearance is generous. It is sturdy and non-slip.
1. Instruments
1. The power supply of the test instrument can output a DC voltage of 100V±2V, and the measurement result can be accurate to within 5%, and can ensure that the energy consumed on the sample for testing anti-static shoes is not more than 3W. The accuracy of the voltmeter and ammeter of the instrument is 2.5, and the range can meet the measurement requirements;
2. The inner electrode is composed of steel balls with a total weight of 4KG and a diameter of 5MM, and must be subjected to anti-oxidation treatment before use;
3. The outer electrode is a copper plate, which must be treated with anti-oxidation and cleaned with ethanol before use.
2. Preparation of test samples
1. Sample preparation
Clean the sole surface of the anti-static shoes under test with ethanol, then wash the sole with distilled water, and dry it according to the specified conditions;
2. Measurement of resistance value of conductive coating
The device for measuring the resistance value of the conductive coating consists of three conductive metal pillars, the radius of the top of the metal pillar is 3MM±2MM. Three poles on both sides are separated by 35MM±0.2MM, and are connected by metal wires. The third post is 160MM±5MM away from the midpoint of the other two posts, and is insulated from the other two posts.
Put the shoes coated with conductive layer on the specified metal post. The forefoot part of the shoe should be placed with two columns separated by 35mm, and the heel part should be placed on the third column. All three columns must be in contact with the conductive coating. Then use the specified test instrument to measure the resistance between the three poles on the front two sides and the third pillar. The measurement result of the measuring circuit principle must be less than 1KΩ.
3. Test conditions of anti-static shoes
1. Environmental requirements: temperature 20℃±2℃; relative humidity: 30%±3%;
2. Place the test sample under specified environmental conditions for more than 24 hours;
3. If the test cannot be performed in the specified environment, the test must be completed within 5 minutes after the test sample is removed from the environment.
4. Anti-static shoes test steps
Fill the test shoes with steel balls as required. If the height of the upper is not enough to fit all the conductive steel balls, the height of the upper can be increased with insulating materials. Put the installed steel ball test sample on the specified external electrode, connect the specified DC power supply between the inner and outer electrodes, time 1min, measure the circuit principle, record or calculate the voltage value and current value after reaching the specified time .