Abstract: Float-controlled electrical switch (11) includes a reed contact (22) which is opened and closed by the field of force of a permanent magnet (32). The permanent magnet is embedded in a float which can be moved by rising and falling liquid levels towards and away from the reed contact for closing and opening of the reed contact. The reed contact (22) cooperates with a relay (25) which provides for engaging and disengaging of a working contact (18) for engagement and disengagement of a bilge pump (10) or another power device in connection with inspection of two separate liquid levels. Provision is made for a large distance between the liquid levels together with markedly distinct positions for engagement and disengagement of the reed contact by allowing the electromagnetic field of force of the coil (24) of the relay (25) to cooperate with the field of force of the permanent magnet.

Abstract: Apparatus for warning of the increase in draught of a floating article, especially a small boat, in a surrounding liquid. The apparatus includes a signal emitter and a source of current which are connected, via a relay and a switch, to a release unit. The release unit includes a chamber fixedly arranged relative to the article which communicates with the surrounding liquid. The chamber holds a contact device which is adapted to close an electrical circuit when the liquid has risen to a certain level in the chamber.