What you want to ask is the reason why Shanghai Yitai f96b ship insulation tester didn't give an alarm? The reason is that the test meter is not connected correctly and the test meter is faulty.

1. Incorrect wiring of test meter: Correct wiring of ship insulation test meter is very important. If the wiring of the instrument is incorrect, there may be no alarm. At this time, it is necessary to check whether the wiring of the test meter is correct and ensure that each terminal is connected correctly with the power supply, measuring instrument and circuit under test.

2. Detection instrument failure: If there is a failure in the detection instrument itself, it may also lead to no alarm. At this point, the test instrument needs overhaul or replacement.