Gps Synchronisation - Iridium Sealite SL-510-SA Installation & Service Manual

The SL-510-SA lanterns are fitted with GPS and provide the user with the ability to install
independently operating lanterns that all flash in synchronisation.
No additional power supplies, aerials or control systems are required, and with its microprocessor-
based system, the GPS option is specifically designed to provide maximum reliability and performance
over a wide range of environmental conditions.
Operating Principle
Each light operates independently and requires no operator intervention. A minimum of 4 satellites
need to be in view for the built-in GPS receiver to collect time data. At dusk, the light sensor will turn
the light on. If time data is available, the light will come on synchronised to every other light with the
same selected flash code.
Synchronisation is achieved using an internal algorithm based on the highly accurate time base and
time data received from the satellites. The satellite data is provided from several earth stations using
atomic clocks as the time base. Continuous self-checking ensures that the light will continue to run in
synchronisation.
Light Activation
At power-up the microprocessor checks that the internal GPS module is programmed correctly and
can provide valid time base and time data.
Once outside with a clear view of the sky, valid data should become available within 20 minutes.
Daylight Operation
During daylight hours the microprocessor is in idle mode to reduce power consumption. Time data
continues to be updated once per second. The microprocessor will automatically exit the idle mode as
soon as dark conditions are detected.
Dark Operation
When dark conditions are detected the light:
• Checks for valid time data and is turned on after a delay based on the current time and the
length of the selected flash code;
• If valid time data is not detected the light will turn on after approximately 10 seconds. This light
will not be synchronised;
• If the light turns on unsynchronised it will continually check for valid time data. Once valid data is
found the light will automatically synchronise.
Note: Lights will not synchronise if they are set to different flash codes.
Latest products and information available at www.sealite.com

GPS Synchronisation

5-9NM Stand-Alone Marine Lantern
SL-510-SA
41