What does a bright green LED indicate when testing a telephone line for voltage and polarity?

A bright green LED indicating a clear working line with correct polarity shows that the telephone line has adequate voltage and is functioning properly. In telecommunications, when testing phone lines, a bright green light typically signifies that the voltage is within the acceptable range for operation, indicating to the technician that the line is connected properly and there are no issues with the signal strength or polarity.

This functionality of the LED is crucial, as it helps technicians quickly assess the line's status during troubleshooting. A bright green indicator gives confirmation that both the voltage levels and polarity are correctly aligned for the equipment being used, allowing normal operation of telecommunication services.