The network is due to be fully operational by April 2016.
The first camera became operational in Ngauranga Gorge, Wellington, in July 2014.
Counties Manukau Road Policing Manager Inspector Alison Brand said there had been 15 crashes in the vicinity of the Great South Rd site in the past 10 years.
Although none had been fatal, three were serious and 12 were minor or non-injury crashes.
"This is a lower crash rate than the other Auckland sites selected for speed cameras, yet the road is considered high risk due to the high volume of traffic travelling this road each day," Ms Brand said.
"I have no doubt this camera has helped us to manage speed on this road and reduce speed-related crashes, and the upgraded camera will continue to do so."