Local resident Siobhan Foster said she was incorrectly issued a ticket in November 2014 after parking in the CBD for less than the then two-hour limit.
It took an email to the council from her friend, proving that she was not in the CBD at the time she was supposed to have originally parked, to have the $15 fine waived, she said.
She said the experience had made her wary of going into parking spaces too quickly after other cars.
"What do you do if you can't prove you weren't there?"
Mr Foster said incorrect fines were a result of technical issues with the sensors.
"This has occurred on occasions where the sensors - often due to low batteries or damage - have not immediately re-set when a car leaves a park and another car enters straight away.
"The average life of the batteries used in the sensors is three years.
"There are sometimes also issues caused by damage and weather conditions. All issues are tended to by Smart Parking, which is contracted for the upkeep, maintenance and data management of the sensors, including software and technology updates."
He said there had been no issues caused by geothermal activity.
His comments followed those made at a recent council committee meeting by Stavros Michael, the council's transport solutions director, that the sensors can take about three minutes to reset between each park.
This suggestion was rejected by John Heard, the chief technical officer for Smart Parking.
"The assertion of such functionality taking minutes is totally unfounded, and would be completely untenable for any viable parking system," said Mr Heard.
Mr Heard said the average time taken for a sensor to detect a vehicle departure was about one second.
Yesterday, Mr Foster said Mr Michael did not make an assertion about the functionality of the sensors.
"He commented about occasional issues that occur " about two per week out of more than 1500 sensors we have in place."
Mr Heard said it was inevitable that sensors would occasionally experience technical issues - "that's a fact of life" - but that there were safeguards in place to prevent against the issuing of incorrect fines.
Council staff are working with Smart Parking to fix the issues.
Sensors in inner city
Free, unlimited time spaces: 264
Mobility spaces: 67
15-minute spaces: 192
60-minute spaces: 136
90-minute spaces: 367
Metered and pay-and-display spaces: 525
What do you think?
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