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سؤال 182

Why should soldered joints not be used in lightning protection ground connections?

  1. A soldered joint will likely be destroyed by the heat of a lightning strikeپاسخ درست
  2. Solder flux will prevent a low conductivity connection
  3. Solder has too high a dielectric constant to provide adequate lightning protection
  4. All these choices are correct

توضیح

A lightning strike delivers tens of kiloamps, and the resistive heating in the joint is far more than enough to melt the solder, which liquefies at under 200 degrees Celsius. The connection would open at the moment it is most needed, so lightning ground connections use clamped, crimped or exothermically welded joints instead.

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شروع تمرین
سؤال 182: Why should soldered joints not be used in lightning… · FCC General Class (Element 3) · Questena