The ring conductor is connected to which voltage?

The ring conductor is connected to which voltage?

• A. Positive DC signal voltage
• B. Ground voltage
• C. Negative signal voltage
• D. AC signal voltage

Answer: (C)

The ring conductor carries the negative side of the DC supply on a two‑wire telephone loop. In typical POTS wiring, the central office applies a DC bias across the pair (about 48 V), with the Tip side sitting at a higher potential and the Ring side at the negative potential relative to that. The ringing signal, which is AC, is superimposed across the pair, but the Ring conductor remains the negative side of the DC bias. Ground is not the direct supply path for the ring in normal operation. That’s why the Ring is described as being connected to negative voltage.

The ring conductor carries the negative side of the DC supply on a two‑wire telephone loop. In typical POTS wiring, the central office applies a DC bias across the pair (about 48 V), with the Tip side sitting at a higher potential and the Ring side at the negative potential relative to that. The ringing signal, which is AC, is superimposed across the pair, but the Ring conductor remains the negative side of the DC bias. Ground is not the direct supply path for the ring in normal operation. That’s why the Ring is described as being connected to negative voltage.