Each year an alarming number of strain gage load cells are destroyed by lightning. In reality, however, very few cells receive direct strikes. Statistical evidence shows that the vast majority of cells supposedly hit by lightning are actually damaged by induced voltages. These voltages can cause the modulus resistors to open like small fuses, or they can cause arcing between the gages and the substrate. In many cases it can be shown that scale indicator power supplies pass line transients onto the excitation lines. It is these transients that are often the source of load cell damage.
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