A refrigerator should only run for maybe 5 to 15 minutes at a time every hour or so.
The refrigerators compressor is not on and running all the time throughout the day but instead the refrigerator compressor comes on when the temperature drops below the thermostats set temperature and then runs until the temperatures gets cold enough again to shut off.
So if your refrigerators compressor is constantly running then the refrigerator is not sealing properly or there is something wrong with the refrigerator.
Some refrigerators may cycle on and off every 25 to 30 minutes which can be normal depending on how much food you have in the refrigerator and how warm it is in the house.