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Spurs on a ring, and the reading that catches people outThe socket reads higher than its spur. Why?

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A spur is a branch off the ring. The ring test does not include it — your three steps are proving the ring itself.

A spur reads higher than the ring

Because there is extra cable, and more length means more resistance. If the ring reads 0.04 Ω at step 2, the spur comes in above 0.04 Ω. You are not asked to calculate it — just to expect it higher.

If the spur is not a socket. On a fused connection unit, drop the front cover and probe into the back of it.
✋The trap. Sometimes the socket the spur is connected into reads higher than the spur itself. That socket has more conductors in its terminals, and one may not have been fully caught — a loose connection driving the reading up. That is a fault, not normal behaviour. If the higher reading is not the spur, open it up and look.

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