In copper testing, what does distance measurement indicate?

• A. The distance to the nearest junction box.
• B. The shield's circumference.
• C. The measured length of the cable from tester to far end.
• D. The distance a signal can travel before reflection.

Answer: (C)

In copper testing, distance readouts show the physical length of the installed cable from the tester to the far end. The tester sends a quick pulse and measures how long it takes for that signal to travel to the end (and back, if needed). Using the cable’s known propagation speed (velocity factor), it converts that time into a distance, giving you the actual length of the run. This helps verify the install length and, if a fault exists, locate it along the run by identifying where a reflection occurs.

This isn’t measuring the shield’s circumference, nor simply the distance to a junction box, and it isn’t describing how far a signal could travel before reflecting in a general sense. The distance readout is about the physical length of the cable from the tester to the far end (or to a fault point determined by reflections).