1. Junction Boxes for KM3NeT
R. PAPALEO
Junction Boxes for KM3NeT

2. 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

3. 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)

4. Underwater Connectors Reliability
ODI (2006 report)
SEACON

5. 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)

6. 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)

7. 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

8. 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

9. 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

10. 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

11. Antares Junction Box

12. NEMO Junction Box

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

14. 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

15. 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

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

17. 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

18. 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

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

20. Example of a cabled observatory: SN-1