When it runs it does heat and run normally? That would generally mean it is OK internally, if there was an internal short that would usually happen very shortly or immediately after starting. It should also be caught by the 30A dryer breaker (which is 2 120v 30a tied together or one double breaker)not the main, which is probably closer to 200A depending on your service.

In 10+ years of this I've never come across a dryer tripping the main as that handles a larger load and could be a safety issue since a ~180A or greater draw somewhere is a significant amount, you may want an electrician involved here.