It’s been a while since I last posted. I’d like to ask gently: have you used lightning-proof level gauges and pressure gauges?
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It’s been a while since I last posted. I’d like to ask gently: have you used lightning-proof level gauges and pressure gauges? Protection of instruments against lightning strikes has roughly three meanings: first, it prevents lightning induction; second, it protects against surge impacts; third, it safeguards against overvoltage and overcurrent. The protection of instruments against lightning strikes is achieved through a bypass protection circuit, whose working principle involves quickly discharging abnormal energy and promptly blocking the path through which such energy can reach the amplification circuit. Therefore, a proper grounding of the shielding layer is extremely important! Brother Pig, please remember: if proper grounding isn’t done, it’s completely useless for protection! No matter how well-designed the lightning protection circuit is, it’s useless. Why? Because a lightning protection circuit isn’t a battery or an energy storage device; it’s rather a device for rapid energy discharge. If the grounding isn’t proper, when large amounts of energy are discharged, it can cause problems similar to those caused by a dam breaking – serious overheating can lead to disasters, you know what I mean :) Here are some pictures of lightning protection devices. Today, I feel a bit uneasy in my chest… Is God thinking about sending rain and thunder?
It is estimated that those working on the dry instruments don’t understand lightning protection and grounding.
For ordinary, lightning-proofless 2-wire 4–20mA instruments, does their signal cable have a shielding layer? And whether that shielding layer is grounded or not – the actual impact on the signal is extremely minimal, practically equivalent to zero. Even if the shielding layer is grounded, it serves no purpose in terms of lightning protection. Why? Because the probability of a direct lightning strike is virtually 0.000000000000000000000000000000000000000000. For example, very few people die from lightning strikes worldwide each year. As for induced lightning strikes, they usually affect the power supply first, causing it to fail before affecting the signal cables. I’ve never heard of a case where the power supply isn’t damaged but only the level gauge or pressure gauge is ruined. Has anyone encountered such a situation? If so, please share your experience and help me understand better. In other words, whether the shielding layer of a lightning-proofless instrument is grounded or not, it cannot dissipate high voltages or high currents:lol
A few years ago, during the typhoon season at our factory, we experienced three cases of lightning strikes; the first time, a transmitter located halfway up the tower was damaged by a lightning strike； During the second DCS incident, one of the cards in the Huo family’s system failed completely for all its individual channels; the other channels were not affected. However, as a precaution, the card was still replaced ； On the third occasion, at DCS Hengjia, the entire circuit board failed, causing the whole plant to shut down. After leaving, I heard that a German contractor was hired to carry out lightning protection work on some of the key protected areas; the specifics are unknown.
The glass tube level gauge I use has never been struck by lightning: lol
It’s easy to understand why the field instruments need protection against lightning strikes, but on the DCS side, surge protection must be installed in areas prone to lightning storms; this way, high voltage currents are blocked by the surge protection, preventing damage to the circuit cards.
Even those that aren’t charged can get hit: lol
If it breaks, replace it; an on-site instrument doesn’t cost much. No matter how well-made it is, if it’s hit by a direct lightning strike, the on-site instrument will still get damaged!
Did a direct lightning strike hit the instrument enclosure? The probability of such an incident occurring is approximately 0.0000000000000000000000000000. As for induced lightning strikes and similar phenomena, they occur quite frequently in some areas, such as Sichuan, Hubei, and Hebei. Induced lightning strikes affect instruments through the electrical grid; when this happens, it often damages a whole series of devices. :lol Although there are lightning protection systems and power surge protectors in front of the instruments, when lightning strikes with voltages of dozens or even hundreds of kilovolts occur, it’s still common for some devices to be damaged despite these protections. Additionally, it is said that instrument damage can also occur when there is a power outage in a factory and then the power is restored suddenly It is said that some factories will suffer huge losses? So I think it’s really necessary to install a circuit on the instrument that can protect against lightning strikes, surges, and overcurrents. A lightning protector costs only a hundred or so yuan; investing that amount of money to get such protection is definitely worth it :lol