An assembly controls the liquid level in a vessel in which a submersible pump is disposed. The assembly has a switch housing and a float housing, arranged proximate to each other. A switch in the switch housing selectively energizes a motor associated with the pump. When a float disposed in the float housing moves in response to a change in the liquid level of the vessel, the movement is coupled to the switch by a pair of magnets arranged in attractive relationship to each other. One of the magnets is in the switch housing and the other is in the float housing. The magnets interact by providing force fields that acts through a wall that separates the switch housing and the float housing. A lever on which the switch housing magnet is positioned tilts the magnets away from alignment as they approach each other, reducing the increase in attractive force therebetween.