The 2 most common part(s) or condition(s) which cause the symptom Dryer trips breaker are listed below starting with the most likely. Check or test each item and watch any available videos.
If the dryer trips the home's circuit breaker, the breaker itself might be defective. Over time circuit breakers can become weak and may trip often, even though the amperage draw is below the limit. If the dryer has been checked and seems to be fine, consider having an electrician replace the circuit breaker.
RepairClinic Item # 158
Although not as common, if the dryer trips the circuit breaker the drive motor may be defective. When drive motors fail, they sometimes short out internally and trip the circuit breaker.