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How to do a good job of lightning protection work of electromagnetic flowmeter

First of all, the lightning climate is also becoming more and more frequent. As a high-precision electronic digital instrument, the intelligent electromagnetic flowmeter can prevent the equipment from being damaged due to lightning strikes during use, and even cause major losses, which requires close attention of equipment management personnel. Question, then how do we make the converter of the electromagnetic flowmeter not be struck by lightning?

First, we need to understand the two main forms of lightning. One is the lightning generated by the discharge between different clouds, the other is the lightning phenomenon caused by the cloud-to-ground discharge, and the main damage to the electromagnetic flowmeter is the discharge of the cloud to the ground. The impact of lightning on the flowmeter mainly comes from direct lightning strikes, lightning static induction and other factors. Therefore, in order to prevent the electromagnetic flowmeter from being damaged by lightning strikes, we need to take the following lightning protection work:

The electromagnetic flowmeter is a kind of precision instrument. It is a flow meter that relies on electromagnetic induction. It mainly supplies a stable excitation current to the excitation coil of the electromagnetic flow sensor through a converter. The preamplifier amplifies and converts the electromotive force induced by the sensor into a standard. The current signal or frequency signal facilitates the display, control and regulation of the flow. Lightning gas invades the instrument through the power supply. The lightning generated by the powerful magnetic field instrument electronic components generates magnetic induction, instantaneously generates strong voltage and current, and breaks through the insulation and burns out the instrument. The lightning pulse wave invades the flow meter through the wireless network to burn out the communication chip or meter. In the summer of the upcoming thunderstorms, lightning strikes have become a major safety hazard with the use of electromagnetic flowmeters. The following is a small series of measures for electromagnetic flowmeters to prevent lightning strikes during thunderstorms in summer. Not only need to pay attention to these matters during thunderstorms, but also pay attention to them during the initial installation and use. These points can be prevented in the first place.

Electromagnetic flowmeter lightning protection: the length of the lightning arrester grounding wire can not exceed 1M, and the cross-sectional area is larger than 6MM square stranded copper insulated wire. If there is no ground net nearby, a simple net should be made near the arrester. The method is as follows: three flat steels or angle steels with a length of 1.5M are used to drive into the ground in a regular triangle arrangement, and the flat steel bars are used to weld the three flat steels. In one of the corners, the bolts are welded, and then the grounding wire of the arrester is connected to the 220 VAC lightning grounding plane to install the panel. The signal cable length between the converter and the sensor must not exceed 50M, and the signal cable must be sheathed with a galvanized tube. If the galvanized pipe is in the air, the galvanized pipe should be reliably grounded with a grounding resistance of less than 10. The power supply is 220v one-way AC, and an air switch is installed in the instrument box. The arrester and the air switch are connected in parallel. The wire is connected from the air switch and then connected to a three-terminal socket.

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