How to detect the anti-static ground wire of the workshop
Although many electronics factories have installed anti-static grounding, they are not qualified for detailed inspection. It is recommended that enterprises with high static electricity requirements should use the instrument for testing when installing static grounding. You can also ask professionals to make measurements.
(1) All anti-static grounding wires use 6 mm2 multi-strand copper core insulated wire. Each floor or appropriate section uses copper bars or 401 switches. The knives are connected with the main line to facilitate inspection and maintenance.
(2) The anti-static cable should be well insulated from the equipment casing, workbench iron frame, work light frame, etc. to prevent short circuit, lap or broken connection.
(3) In the "trunk end" of the segmented copper row or switch, another inspection line is provided. (1.5~2mm2 can be used). Each workshop has 2~3 checkpoints, which are fixed and clearly marked.
(4) Measurement: use a pointer multimeter, resistor file, or use a grounding resistance tester (also called a shaker).
The resistance between each anti-static test point and the anti-static ground wire is 5~15Ω, ideally it should be 0Ω. But the actual measured value is 2mm2 wire from the test point to the summing point resistance +6mm2, the wire is from the summary point to the resistance of the measured point. And, this value is about 5-15Ω and basically unchanged. If the measurement result tends to infinity, it is a broken line for the anti-static ground wire or measuring line, which should be repaired in time.
Anti-static ground and equipment ground resistance, this resistance is the anti-static ground wire itself line resistance + equipment ground wire itself line resistance + ground wire resistance between the two ground. But the ground wire is wet and dry due to ground level, ground current The influence is very complicated, especially the current, the frequency in the direction and the direction of the moment is changing, and the measurement result is mainly determined, so it can only be measured by the pointer meter, and its value is normal from ten to several hundred K. Only the two places are not short-circuited or open.