Both systems comprise a set of three solar powered lanterns, with flash codes synchronised by GPS and commanded on/off by a low power radio link. The lanterns are controlled from a base station in the harbour master's office. The base station houses a transmitter/receiver with a push button to activate the lanterns and a 'telltale' indicator to show the commanded status of the lantern. This button opens and closes the transmitter's digital input, broadcasting to the receivers located in each set of lanterns and operating their output relay.

The first set of lanterns, for the commercial harbour, consists of three Tideland ML-300 lanterns with red lenses blanked over 1800 and 50W lamps, giving a daytime range of 800m. Power is supplied by three 80W solar modules feeding a 400ah battery, which is designed to ensure that the lights function without interruption under the low light conditions of the winter months.

A regulator is installed to ensure that the batteries do not overcharge.

The second set, used in the marina, consists of three ML-155 lanterns powered by two 20W solar arrays and a 200ah battery bank, also fitted with red lenses but with 20W lamps and a daytime range of 200m. In both cases, the centre lantern is fitted with a Syncmaster Omnibus II flasher lampchanger and Garmin antenna, allowing the three lanterns to flash synchronously, while all the remaining lanterns have Omnibus II flasher lampchangers.

MJInformation No: 21985