I have noticed a few locations that are marked as Speed / red light camera (dual function). The warning signs on the side of the road say "Red Light Camera Ahead"; they make no mention of "Speed Camera Ahead".
Does this mean that they are actually just red light cameras?
Dual function Safety Cameras are installed to chase red-light runners and to reduce crashes at traffic control lights. Drivers running red lights can be particularly dangerous, especially if a vehicle crashes into the driver or passenger side doors.
The combined road safety cameras detect speeding vehicles, vehicles running red lights, or both.
In summary, do not speed on the intersections as you can loose demerit points for both offences and get separate penalty notices: red light penalty notice +/- speeding penalty notice.
I think NSW is using "Security Camera" for such dual function camera. One of those are on City West Link (Wattle Street) which I witnessed some cars were being photographed when overspeeding across green light.