​Loading order of floor scale

Loading order of floor scale
The floor scale must be constructed with concrete foundation and avoid soft soil. If the area cannot be created due to the limitation of the site, it must be reinforced and drainage facilities should be built to prevent the floor scale from flooding into the water.

During the construction, the concrete mark should be guaranteed, and the position of the anchor bolts and cast iron bottom plate should be guaranteed, and the embedded parts should not be shifted. Secondary grouting legal-position anchor  bolts and cast iron floor plates can be used. The levelness and elevation of each cast iron floor plate must meet the requirements of the design drawings, and the height difference in the same plane shall not be greater than 3mm.Microelectronic technology has been widely used in electronic weighing apparatus, but it is very sensitive to overvoltage, overcurrent, electromagnetic pulse and other external interference and has very low tolerance. In order to ensure the stable operation of the system and prevent lightning damage, it is necessary to design and install the weigher according to lightning strike.

Lightning strike can be divided into two forms. One is direct lightning strike, which is more destructive to the system, but less likely to occur for floor scale. The other is induced lightning strike, which shows that the generated electromagnetic field generates overvoltage or overcurrent in the system. The effect of such lightning strike is mainly uneven charge distribution. The damage of local over-voltage electronic equipment caused by electrostatic induction. According to relevant reports, this voltage can sometimes reach tens of thousands of volts, which is enough to damage the electronics with poor grounding.

To reduce or even eliminate the impact of lightning strike on the weighbridge, the following measures can be adopted.

(1)  Install lightning rod. As the most important measure of the lightning protection system, the lightning rod can also play an important role in the protection of the weigher system. In the design of the lightning rod, the length of the lightning rod should be determined according to the length of the truck scale, and grounding should be done according to the relevant standards.

(2)  According to the grounding and related requirements of DL/ t381-2010 electronic equipment lightning protection technical guidance, the whole weighing platform should be grounded, and there is a spacious large current return channel  between the weighing platform and the grounding pile, which can supplement the electron from the earth and realize the effective protection of the equipment.

(3)  Weighing sensor protection. In the operation of the system, the weighing sensor plays an extremely important role, but it is also more sensitive to lightning. Therefore, each sensor should be protected and grounded. At the same time, grounding piles or grounding grids should be installed below the grounding line to conduct the generated induced current quickly.

(4)  Signal cable protection. In the process of scale load application, will be conducted by signal cable signal transmission, normally the cable has a length, so the lightning easily produce induced current on the cable, may cause damage of header, so the system current need to install the shield on the power cord, shield to ground at the same time, in order to eliminate electromagnetic induction. The shielding layer of the signal cable of the weighing sensor is connected to the ground wire through the junction box or the ground wire of the meter head, which can be determined according to the actual situation.

(5)  The head of the metal case should be grounded. Therefore, a grounding pile is arranged in the pound house and connected with the foundation internal reinforcement network (grounding) of the scale.