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The Instrumentation Unit of The KM3NeT Calibration Unit. KickOff Feder, 21/06/2017 . The Calibration Unit. Independant line dedicated to the calibration of the detector Particularity of the line: inductive line in order to save money Needed for the Calibration in time and in position :
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The Instrumentation Unit of The KM3NeT Calibration Unit KickOff Feder, 21/06/2017
The Calibration Unit • Independant line dedicated to the calibration of the detector • Particularity of the line: inductive line in order to save money • Needed for the Calibration in time and in position : • Calibration in time : inter DU time calibration with the use of laser light emission • Calibration in position : acoustics emitter/receiver for the relative acoustic positioning system • Calibration in position : measurements of oceanographic parameters to know the sound velocity + sea current measurement
The Calibration Unit • Global sketch of the Calibration Unit : CU CPPM APC - Laser : time calibration - Acoustics : relative positioning
The Instrumentation Unit (IU) for the Calibration Unit • Inductive Instrumentation Unit directlyinspired of the Albatross line • The IU iscomposed by one inductive Instrumentation Line (IL) and one titanium Instrumentation Base container (IB) • The IL hosts all the oceanographic instruments linked to the line via an inductive interface thatcommunicatewith inductive modem (SeaBird, rate 1200 bauds) • The instruments are autonomous in terms of energyusinginternal batteries • The IU isrecoverable in order to change the batteries and to calibratesome of the instruments thatneedrecalibrationperiodically (about once every 2 years) • The IU will be connected to the electric interlink cable with a ROV via the IB wet matable connector
The instruments for the CU • The IU islinked to the Calibration Base of the CU via one 50 m electric serial cableusing RS422 serial communication for the data transfert : • 4 electrical points for the RS422 link • 2 electrical points for the 12V power (supplied by CB) The configuration of the IL in order to intrument the full water column of the KM3Net detector for the ORCA version (vertical height 200m) is the following : • 3 CTD probe (Conductivity, Temperature, Depth) theses parameters are used to calculated the sound water speed with the Chen&Millo empiric formula • 3 currentmeter : measures the seacurrent • 3 SV : Sound velocimeter : direct measurement of the sound velocity One measurement of each instrument every 20 minutes, transmitted in «real time» to the CB
The instruments of the IU - CTD fromSeaBird : (SBE 37IMP-ODO-1b) Inductive instrument - Sound Velocimeter from Valeport MiniSVS : • Range:1375-1900m/s • Resolution: 0.001m/s • Accuracy: theoretical max error from ±0.017m/s to ±0.02 m/s depending on sensor size. Non Inductive instrument and non powered : need an extra serial/inductive interface - Currentmeter : Aquadopp6000 from Nortek : • Local measurement of the sea current • Range: ± 3m/s • Accuracy: 1% of measured value ± 0.5 cm/s Non Inductive instrument : need an extra serial/inductive interface Could be replaced by ADCP : Acoustic Doppler Current Profiler (current profile on the water column)
Status of the IU • Test bench operationnal in CPPM : Simul. Inductive cable Simul. Inductive cable coupler Simul. IU Manager (CB) IMM : inductive modem • all instruments (CTD, currentmeter, celerimeter) are nowcorrectlyinterfaced and configured via inductive modem. • Launch of measurement and retrieve of the data are operational UIMM serial/inductive adapter : to interface Aquadopp currentmeter
Status of the IU • Mechanics : • Global mechanics design almost completed • Global deployment steps defined Full detailed deployment procedure under redaction