Junction Boxes for KM3NeT R. PAPALEO Junction Boxes for KM3NeT

KM3 Junction Box Main common requirements and constrains Junction Box for the KM3 detector: Mechanics Housing for pressure and corrosion resistance (single vessel, double vessel technology) ROV underwater connector interfaces Frame for deployment and recovery Cable system Breakouts for the management of the DUs Beacon for the LBL of the acoustic position system Power management system Transformer (AC, AC triphase, DC/DC) Slow control electronic system for JB management Optical management system for the data transmission In case of secondary JBs the optical system should work with DWDM technology in order to reduce the number of optical fibers towards the primary JB

Interlink connection ROV underwater connectors Hybrid ROV wet mateable connector Optical and electrical pin in a single connector Only 1 company on the market (ODI) Electrical underwater and optical underwater connectors Electrical connectors: 3 companies on the market (ODI, SEACON, GISMA) Optical connectors 2 companies on the martket (ODI, SEACON)

Underwater Connectors Reliability ODI (2006 report) SEACON

Interlink connections 3 solutions for interlink connection between underwater structures (JBs and DUs) Point to Point Interlink 2 ROV underwater connectors Interlink cable Point to Fix Interlink 1 ROV underwater connectors Fix to Fix Interlink Interlink cable requirements (common for all the DU solution) 2 optical fibers (Data transmission) More than 2 electrical wires (power supply and slow control) Length = f (geometry)

It’s necessary to consider the management of the interlink cable: Interlink connection It’s necessary to consider the management of the interlink cable: During the installation On the maintenance operation (100 DUs means about 30 km of interlink cable) On the up-grade of the telescope (if foreseen)

Point to Point interlink LInterlink Cable= Distance between structures (JBs – DUs) 2 ROV connectors (hybrid solution) 4 ROV connectors (electrical and optical solution) 2/4 ROV sea operations Detection Unit

Point to Fix Interlink Point to Fix Interlink LInterlink Cable= Distance between structures (JBs – DUs) 1 ROV connectors (hybrid solution) 2 ROV connectors (electrical and optical solution) 1/2 ROV sea operations Detection Unit

Fix to Fix Interlink Fix to Fix Interlink LInterlink Cable= depth of Site + % 0 ROV connectors 0 ROV sea operations for underwater connections Detection Unit

KM3NET Junction Box Lesson learned ANTARES has built and deployed a JB in december 2002 Single Vessel Technology (Titanium) Dry connector with the main EOC Failures 3 wet mateable connectors (ODI) out of service JB it’s working since 2002 NEMO (Phase1) has built and deployed a JB in december 2006. Double Vessel Technology ROV underwater connector for connection with the main EOC Electrical failure due to crash on the ship during the sea operations Optical failure due to defective ODI components Recovery of the Junction Box, Maintenance operations and deployment of the Junction (it’s working since April 2008) Similar characteristics ROV Hybrid wet mateable connector interface for the connection of the DUs Power transformer in oil Breakouts for the management of the DUs

Antares Junction Box

NEMO Junction Box

JB – DUs Connection System Antares JB Connector Panel NEMO JB Connector

Proposal for a standard JB for the KM3 detector Life time = > 10 years (following KM3NeT requirements) Project of the pressure vessel for the max operative depth Mechanical frame for the deployment and recovery system ROV underwater connectors for the connection at the DUs and at the main electro optical cable To simplify installation To simplify the maintenance Outuput with ROV underwater connectors To be defined if Hybrid or Electrical + Optical connectors Standard position of the ROV underwater connector in order to define and realize standard ROV connection operations

Proposal for a standard JB for the KM3 detector N.2 optical fibers for the connection of the JB with the DUs Standard Pins Configuration Same position on all the connectors for the Optical fibers and electrical conductors Standard Power Supply System Beacon power supply system and management for the LBL of the detector

on behalf of INGV and TECNOMARE SEAFLOOR OBSERVATORY GENERAL REQUIREMENTS R. Papaleo on behalf of INGV and TECNOMARE

Seafloor observatory: general requirements Communications (ref. SN-1): real-time, bi-directional high-bandwidth communication to the seafloor observatory through two single mode optical fibres (one used, one spare) using 1310 and 1550 nm wavelengths 10/100 Ethernet communication RS-232 standard interfaces to sensors GPS/PPS timing synchronisation at seafloor using media converters to convert electrical communication and timing signals to optical form Power (ref. SN-1) voltage: 500 VAC monophase 50 Hz power required by the observatory ~100 W Umbilical cable: hybrid electro-optical, minimum 2 x 4 mm2 power conductors 2 SM optical fibres INGV

Seafloor observatory: interfaces ROV underwater mateable ODI connector to interface with the umbilical, through a dedicated J-BOX Standard underwater electrical connectors to the scientific payload INGV

GEOSTAR-class observatory scientific payload (ref. SN-1) INGV

Example of a cabled observatory: SN-1