Yes, there is such a "thing". But you are using circuit in a very broad context. The only thing that I may compare this to is the amps going to your house. Many houses come with 200 amp boxes, or more.
Yes, there are 30 amp circuits and they are available in 120, 208, 220, 277 and 480 volts respectively. Most 30 amp circuits are used for water heaters, motors and appliances.
