If the TS100 has a fault, it comes not from the iron itself but from its cable. A high-grade iron will have an extra-flexible PVC or silicone cable, but the TS100 does not have a cable of its own.

This circuit was designed to allow microphone cables or other cables to be easily tested for intermittent breaks that can often be difficult to find using a multimeter. The circuit can test cables ...

A multimeter and its test leads allow electrical workers to reach into an energized panel, touch live circuit components with the end of the test leads, and capture electrical readings like voltage, ...