Signature management systems

Advanced Impressed Current Cathodic Protection (ICCP)

The galvanic corrosion effect from ships is a result of the use of dissimilar metals. The seawater, propellers and hull act as the inside of a battery. The battery creates a current flow in the seawater from the steel hull to the non-ferrous propellers. An ICCP system designed by EMS consists of current anodes that surrender their current to the propeller in place of the steel-sacrificing current, thus inhibiting and stopping corrosion of the steel. This circuit inside the 'battery' is the mechanism for the creation of the Underwater Electric-field Potential (UEP) signature due to corrosion and the ICCP system.

The completion of the 'battery' circuit is the return current path from the propeller to the hull when no ICCP is present, or from the propeller to the anodes (or ICCP power supplies) with ICCP systems present. This circuit can be considered the circuit outside of the 'battery' and consists of the propeller shaft, the shaft bearings, the hull and the anode grounding circuit. This generation of current both in the seawater (inside the battery) and in the ship's propeller shafts and hull (outside the battery) is the mechanism for the creation of the Corrosion Related Magnetic (CRM) signature of the vessel.

EMS specializes in the design, manufacture and calibration of advanced ICCP systems that prevent the corrosion of the ship's hull and minimize the UEP and CRM signatures. This is achieved by the design and architecture of the total ICCP system and by the use of advanced ICCP system and by the use of advanced ICCP control algorithms.

Advanced ICCP systems:

  • Advanced Mil-Spec systems with low noise and high accuracy
  • Mil-Spec shock, vibration, EMI/EMC and environmental
  • Complex computer control with multi-zones together with semi-distributed or fully distributed architectures

Integration and installation of degaussing, ICCP and shaft grounding systems:

  • Integrated control, operation and maintenance
  • Technical support for calibration, light-off, ranging and deperming
  • Documentation and specification, algorithms for calibration

Advanced ICCP advantages over traditional ICCP:

  • Reduces UEP and CRM signatures typically 50-75% reduction, often more than 80%
  • Better survivability and availability
  • More stable operation and control
  • Lower current and power drawn
  • Modular system – spares list is optimized
  • Advanced communication architecture with ship's control systems
  • Integration and communication with ASG/PSG