Which of the following statements regarding the electrical and mechanical characteristics of the isolator is true after the short circuit test?

After a short circuit test, it is crucial for the isolator's electrical and mechanical characteristics to remain unchanged. This is because an isolator is designed to provide the means for preventing the passage of electrical current when it is in the open position, and it must retain its integrity and operational capabilities after being subjected to a short circuit event. The purpose of such tests is to verify that the isolator can handle fault conditions without sustaining damage that would affect its future performance.

If the characteristics were to be permanently altered, improved, or modified as a result of a short circuit test, it would compromise the reliability and safety of the isolator in future operations. Therefore, the expectation is that after testing, the isolator should still perform its intended function without any degradation in its properties.