My APC UPS has been reporting supply conditions as low as 160V AC and as high as 260V AC at approx. 1745 hours.
I've got all high load items (oil coloumn heaters) turned off and the power I am using has not exceeded 3.5KW/h during that time.
Granted, I am in an old 3 story Victorian style draughtbox but haven't had any problems like this before.
Just interested to see if anyone else has noticed problems in the Botanic Gardens/CBD area of Wellington.