We are presuming that you have a Grundfos 301 controller. That is going to be indoors. To send 230 directly to the pump, you would bypass the CU301 temporarily. However you would control the pump with the breaker for testing. If you took that CU301 out of the circuit forever, to fill a tank, you would use a float switch, and probably also that pump protection device.
It could be useful to use a clamp-around ammeter to measure the current when you turn on the pump, and see what happens as you approach the shutting down.
It could be useful to use a clamp-around ammeter to measure the current when you turn on the pump, and see what happens as you approach the shutting down.