A DC power system, having: a main bus, a plurality of power delivery devices configured to be connected to the main bus, a first zone partitioning device, and a control system, wherein the first zone partitioning device is configured to segregate the main bus into a first protection zone which is a section of the main bus to which power delivery devices with a fault clearance requirement in a first time range are configured to be connected, and a second protection zone which is a section of the main bus with a fault clearance requirement in a second time range, which includes times that are higher than any time included in the first time range, and to which no power delivery device with a fault clearance requirement in the first time range is configured to be connected, wherein the control system is configured to control the first zone partitioning device to allow load current to flow from the first protection zone to the second protection zone and to limit fault current flow from the first protection zone to the second protection zone.

A DC power system, having: a main bus, a plurality of power delivery devices configured to be connected to the main bus, a first zone partitioning device, and a control system, wherein the first zone partitioning device is configured to segregate the main bus into a first protection zone which is a section of the main bus to which power delivery devices with a fault clearance requirement in a first time range are configured to be connected, and a second protection zone which is a section of the main bus with a fault clearance requirement in a second time range, which includes times that are higher than any time included in the first time range, and to which no power delivery device with a fault clearance requirement in the first time range is configured to be connected, wherein the control system is configured to control the first zone partitioning device to allow load current to flow from the first protection zone to the second protection zone and to limit fault current flow from the first protection zone to the second protection zone.

A remote control system of outboard motor configured to operate the outboard motor through communications with the outboard motor. The remote control system includes an operating lever operated by a boat operator and a motor unit configured to give reactive force against the operation of the operating lever. The motor unit is configured to give the reactive force according to an operating direction of the operating lever and at least any one of an operating speed and a lever position of the operating lever.

A remote control system of outboard motor configured to operate the outboard motor through communications with the outboard motor. The remote control system includes an operating lever operated by a boat operator and a motor unit configured to give reactive force against the operation of the operating lever. The motor unit is configured to give the reactive force according to an operating direction of the operating lever and at least any one of an operating speed and a lever position of the operating lever.

A boat having an electric motor coupled with an electrical store is disclosed. The electrical store includes a storage element, and positive and negative poles in current-conducting connection with the storage element. An isolating circuit element is operatively connected to a user activatable emergency stop switch. The isolating circuit element is configured to, upon activation of the emergency stop switch, isolate the current-conducting connection between the storage element and at least one of the poles.

A boat having an electric motor coupled with an electrical store is disclosed. The electrical store includes a storage element, and positive and negative poles in current-conducting connection with the storage element. An isolating circuit element is operatively connected to a user activatable emergency stop switch. The isolating circuit element is configured to, upon activation of the emergency stop switch, isolate the current-conducting connection between the storage element and at least one of the poles.

A system for providing marine propulsion is provided including an input shaft driven by a prime mover, a pinion gear coupled to the input shaft, a plurality of planet gears coupled to the pinion gear, a planet carrier having the plurality of planet gears rotationally mounted thereto, and a ring gear surrounding the planet gears and coupled thereto. The planet carrier and ring gear are coupled to internal and external output shafts that are coaxially aligned, which are coupled to aft and forward propulsor elements. The ring gear and planet carrier rotate in opposite directions to provide contra-rotating forward and aft propulsor elements. The ring gear and planet gear are each coupled to rotation altering devices that, when at least one is activated, the rotation of both the planet carrier and ring gear will be altered, thereby altering the rotation of the propulsor elements.

A system for providing marine propulsion is provided including an input shaft driven by a prime mover, a pinion gear coupled to the input shaft, a plurality of planet gears coupled to the pinion gear, a planet carrier having the plurality of planet gears rotationally mounted thereto, and a ring gear surrounding the planet gears and coupled thereto. The planet carrier and ring gear are coupled to internal and external output shafts that are coaxially aligned, which are coupled to aft and forward propulsor elements. The ring gear and planet carrier rotate in opposite directions to provide contra-rotating forward and aft propulsor elements. The ring gear and planet gear are each coupled to rotation altering devices that, when at least one is activated, the rotation of both the planet carrier and ring gear will be altered, thereby altering the rotation of the propulsor elements.

A superconducting current limiter with a bifilar coil winding made of a T.sub.c superconductor (HTS) conductor in a cryostat that includes a solid filler material, where the solid filling material is particularly formed from a granulate, hollow bodies or an open-pored structure and is surrounded by cryogen.

A device for monitoring a boat drive, preferably for monitoring a drive battery of a boat drive, includes a first water sensor configured to switch off the boat drive when a first water level is reached, and a second water sensor configured so as to output a water level warning when a second water level is reached.