A thermistor like this has 3 pins. Whenever this thermistor works, it can supply 300V voltage. In order to design PTC thermistors for 7A current, they must have a negative voltage.
PTH7M220MD2-00 Features
Mount: Panel 3 Pins Tolerance: 20%
PTH7M220MD2-00 Applications
There are a lot of Murata Electronics PTH7M220MD2-00 PTC Thermistors applications.