Submersible Pumps Start Problem?

Sounds like you are missing the pressure tank membrane or it is defective.

Without the cushion provided by the air in the tank, the pump will cycle on and off rapidly trying to maintain the correct pressure in the system. Remember that water is incompressible.

The air bubble allows the pump to run for a while, compressing the air. This then provides pressure for a while until the bubble is expanded back to it's original size, at which the pump turns on again.

Does it have a float?

If so then the float is turning is off after the water drops to a certain level and turning back on when the water rises.

Not sure the pump or the application for which you are using it, so this is a guess.

can you provide any additional details?

It sounds as if the water level switch in the automatic section is too sensitive.

It sees water, starts the pump. It pumps awhile, is sensitive to its own vibrations making it then act like the water level is now low. It shuts off.

Electricity I know, pumps I don't.

Your pump may have a pressure, float or level control switch that makes it start and stop intermittently.

check the flow switch/When in auto the flow switch is in circuit...when in manual it is overidden