The Life Of A Prov-Carbon Float; The Mission - Overview - Kannad PROV-CARBON Manuel Utilisateur

USER MANUAL / MANUEL UTILISATEUR

3. THE LIFE OF A PROV-CARBON FLOAT

The life of a PROV-CARBON float is divided into four phases: Storage/Transport, Deployment, Mission, and
Life Expiry.
(1) Storage/Transport
During this phase, the float, packed in its transport case, awaits deployment. The electronic
components are dormant, and PROV-CARBON's buoyancy control functions are completely shut
down. This is the appropriate status for both transport and storage.
(2) Deployment
The float is removed from its protective packaging, configured, tested and launched at sea.
(3) Mission
The Mission begins with the launching of the float. During the Mission, PROV-CARBON conducts a pre-
programmed number of cycles of descent, submerged drift, ascent and data transmission. During these
cycles it collects CTD, DO and transmittance data then transmits them to the IRIDIUM satellites system.
(4) Life Expiry
Life Expiry begins automatically upon completion of the pre-programmed number of cycles. During Life
Expiry, the float, drifting on the sea surface, periodically transmits messages until the battery is
depleted. Reception of these messages makes it possible to locate the float, to follow its movements
and, if desired, to recover it. PROV-CARBON floats are designed to be expendable, so recovery is not
part of its normal life cycle.
By default, the float transmits a position every 6 hours.
If the battery is depleted before completion of the pre-programmed number of cycles, PROV-CARBON will
probably remain submerged and cannot be located or recovered.

3.1. The Mission - Overview

We call «Mission» the period between the moment when the float is launched at the experiment zone and
the moment when the data transmission relating to the final depth cycle is completed.
During the Mission, PROV-CARBON conducts ascent and descent profiles, separated by periods of
IRIDIUM transmitting and drifting at a predetermined depth. PROV-CARBON can collect data during the
descent, submerged drift, or ascent portions of the cycle, and transmits the collected data during the surface
drift period at the end of each cycle. One cycle is shown in figure herunder.
Figure 2: Schematic representation of a PROV-CARBON's depth-cycling during the Mission.
PROV-CARBON
PAGE : 5 / 70
DATE : 20/12/2007
INDEX : A
REF. : DOC07220