hello,
i want to know if it is possible to speed limit(30mbps) a user for X minutes if he is using more than ex. 150mbps for more than 5minutes.
You can achieve that using queues with a burst
I’m guessing you’re looking for simple queues:
https://help.mikrotik.com/docs/display/ROS/Queues#Queues-SimpleQueue
there’s a good explanation of bursts on the routeros help:
https://help.mikrotik.com/docs/display/ROS/Queue+Burst