Handbook of best practices

At the E2M3A telemetry/controller buoy is based on a Persistor CF2 computer running a
DOS-like operating system. The CF2 has a Motorola 68332 processor, 512 kB of RAM and
uses a 1GB CompactFlash card to store programs and data.
The controller has an 8 channels 12bit A/D converter to monitors internal voltages, currents
and temperatures and 7 RS232 serial data connections to interface:
1. the Globalstar Satellite Modem or allowing access to the system when the buoy is on
deck.
2. the meteo sensors, compass, pyrometer, and infra-red radiometer.
3. the GPS receiver.
4. the underwater SeaBird SBE37 ODO.
5. the underwater Pro-Oceanus pCO2.
6. the underwater Sunburst SAMI-pH.
The Persistor uses digital output lines and a power system monitor to detect failures of
power and switch power supplies to the Seabird SBE37-ODO, meteo sensors, compass,
pyrometer and radiometer, GPS, pCO2, SAMI-pH.
The GPS receiver is necessary to keep the clock of the data acquisition and control
electronics correctly synchronized with the Greenwich Meridian Time and to get the correct
position of the buoy: detection of a position out of a pre-defined "Watch Circle" will generate
an alarm condition.
About Globalstar dial-up mechanism, all calls are initiated by the buoy. At pre-set times the
Persistor turns on the power supply to the satellite modem and waits for several seconds to
give it time to register with the satellite network. The Persistor then sends a series of AT
commands and records various status parameters. If all is well it then sends an AT dial
command to call a dedicated phone line at OGS where an analogue modem is waiting. The
call is answered by a PC running a land station receive software developed by OGS and
written in LabView. The program that answers the call receives an ASCII file of unknown
size in 1024 byte blocks. The buoy controller performs various tasks according to a
programmable schedule to acquire data from all the sensors and instruments to which it is
interfaced.
1.3.5 Energetic autonomy
Historically, deployed autonomous buoys were powered by diesel generators, nuclear power
and wind generators with different degrees of success. The use of batteries (initially nonrechargeable)
started in the mid-1970s due to the progress in technology which got to
reduce power requirements of subsequent electronics and transmission equipment.
Nowadays, most of observatories use a combination of power generators and energy
storage in order to keep the electronics and the transmission system working. There are
observatories whose power supply is through cable. MBARI has a long experience with the
MOOS buoy, the running cost are high and this is the reason why this concept has not been
extended vi . However, these observatories are reduced as consequence of the costs of the
infrastructure.
1.3.5.1 Cabled
In cabled observatories, the energy is distributed by an underwater network consisting in
land power station, nodes, junction boxes and possibly front end distribution to instruments
(low voltage). Two type of design are implemented with either DC power or AC power in the
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