The actual voltage to be applied by the bus and which nodes apply to it are application-specific and not formally specified.

Europe has subsequently harmonised on a nominal voltage of 400/230 volts even though the actual voltage in individual countries has not changed.

Implementation determines the actual voltage, but common levels include (0, +5V) for TTL circuits.

Additionally, 120v and 240v are considered nominal voltages, and actual voltages may be somewhat higher or lower during normal operation.

The actual voltage across the tube may fluctuate.

The actual voltage may be greater or less.

If, for example, the actual voltage at one of the buses is measured to be 136 kV, we have:

The actual voltage varies:

However, the label on a power supply may not be a reliable guide to the actual voltage it supplies under varying conditions.

In general, electrical devices are designed to work with one nominal voltage, which represents a band of possible actual voltages, power factor and AC waveform shapes.