How much should the grounding socket and the actual grounding resistance reach
In order to better serve customers, the ground resistance technical parameters provided by the customers will be more clear. Recently, I often receive different requirements for the resistance of the grounding socket from different industries. The two pictures are used in different places, and the requirements are inconsistent. The technical requirements are customized according to the customer's requirements.
The grounding socket in the figure above is usually used for wrist strap grounding and hanging the wrist strap when leaving the station. Therefore, the two holes are not connected. If special conditions are required, the two holes must pass and the grounding resistance must be Must be declared to the manufacturer to avoid wrong versions.
The customer in the picture below uses the hole of the wrist strap to connect the anti-static table mat. The connection method is completely different from the picture above. The measured ground resistance is also different.
Ground resistance reference values for various industries:
I. Grounding resistance test requirements: a. AC working grounding, the grounding resistance should not be greater than 4Ω; b. Safe working grounding, the grounding resistance should not be greater than 4Ω; c. DC working grounding, the grounding resistance should be determined according to specific requirements of the computer system; . The grounding resistance of the lightning protection ground should not be greater than 10Ω; e. For joint shielding of the shielding system, the grounding resistance should not be greater than 1Ω.
Second, ground resistance tester ZC-8 ground resistance tester is suitable for measuring the resistance value of various power systems, electrical equipment, lightning rods and other grounding devices. It can also measure the resistance value and soil resistivity of low resistance conductors.
3. It consists of a hand-cranked generator, a current transformer, a slide-line resistor, and a galvanometer. All the mechanisms are housed in a plastic case, and a leather case is outside for easy carrying. Accessories include auxiliary probe wires, etc., which are packed in accessory bags. Its working principle uses a reference voltage comparison type.