Hi,
I had a look through: http://www.nzta.govt.nz/resources/stop-and-goes-of-traffic-signals/7.html
It's clear that when the straight light is green and the arrow is green you have the right of way and when the arrow is OFF you have to give way to opposing traffic.
However, I have noticed a lot of situations where the light for straight ahead is RED and the arrow light is OFF. After a while (or before that), the arrow is RED.
I haven't seen a driver/rider that will turn left/right when the arrow is OFF and the straight ahead light is RED so, why is the arrow turning off?
Please let me know if I haven't been clear enough.
Thanks.