International model Single phase UPSs have selectable output voltage which could be done either manually or through software (please refer user manual for details)
The output voltage on these units could be set to 220V or 230V or 240V depending on the incoming mains nominal voltage. By default these units are set to 230V from the factory.
If the output voltage setting is not done correctly then single phase UPSs with bypass feature would report bypass out of range error or synchronization errors under certain mains supply conditions.
Loads which require tight voltage regulation might receive out off range output voltage
If the output voltage setting is left at its default 230V in a 240V mains supply region then UPS would indicate bypass error under certain mains supply conditions. As there exists a 10V difference between the UPS output and the mains nominal voltage this difference added to any momentary voltage variations would create a situation placing the UPS output voltage outside bypassing range.
Hence it's important to configure the UPS output voltage in line with the nominal mains voltage.
Example if the mains nominal voltage is 240V then the UPS output should be selected to 240V as well
On the other hand if the mains nominal is 230V then output voltage configuration need not be performed.
Eg in New Zealand nominal mains supply voltage is 230V@50Hz
*Single Phase units automatically senses the incoming frequency to either 50HZ or 60Hz
** Output voltage selection for line-interactive and standby units relates to on- battery operation only"