Run a 15 amp motor on a 30 amp breaker?
I can't speak to the code issues and/or real-world safety of running a 220V 15A device on a 30A circuit.

However, keep in mind that dryer (and range) receptacles are NOT designed for frequent usage. They are designed to sit untouched for years at a time. Where a regular plug &amp; receptacle might get used a few times a day (and with cell phone chargers and other devices sometimes more often than that), the dryer cord/plug and receptacle may not do well being plugged/unplugged on a regular basis.

In addition, you need to make sure the dryer receptacle is a newer 4-wire receptacle - hot/hot/neutral/ground NEMA 14-30. Older dryers (or rather, older houses never upgraded) use a NEMA 10-30. It is code-compliant to continue using a NEMA 10-30 for a dryer. But you should definitely not use it for a new device. So if you have a NEMA 10-30 then, in addition to any other issues of 15A vs. 30A, etc., you should be upgrading first to a NEMA 14-30 receptacle and change the dryer cord to match and remove the neutral-ground jumper inside the dryer.

Also see: What&#39;s a simple solution to have 2 NEMA 14-30 receptacles and switch power between them? for a discussion of using a switch between 2 receptacles.