7 DESIGN AND INSTALLATION
7.1 DURABILITY AND RESISTANCE TO ENVIRONMENTAL CONDITIONS
Night vision equipment should withstand the environmental conditions specified in resolution A.694(17) and in the applicable IEC requirements*.
7.2 INTERFERENCE
With respect to electrical and electromagnetic interference, night vision equipment should meet the requirements of resolutions A.694(17) and A.813(19) and the applicable IEC requirements*.
7.3 POWER SUPPLY
The power supply of night vision equipment should meet the requirements of resolution A.694(17) and the applicable IEC requirements*.
7.4 INSTALLATION
The controls of night vision equipment should be installed in the workstation for navigating and manoeuvring, within easy reach of the navigator.
The observation distance from the monitor should not exceed 2.3 times the monitor diagonal.
The sensor of the night vision equipment should be installed in such a way that：
- the wide field of view in zero position of the field of view axis is free of obstructions;
- further within the horizontal panning area of the sensor, in the sector up to 112.5° to either side, there are no obstructions with a deepest shadow bigger than 3°;
- two deepest shadows are separated by an unobstructed field of vision of at least 30°;
- in a sector from 112.5°to minimally 175°, and from minimally 185°to 247.5°, deepest shadows are kept to a minimum;
- in the wide field of view, in the direction right ahead, visibility of the water surface for the vertically tilted sensor is not reduced by more than two ship's lengths by the blind angle of one's own craft.
Night vision equipment should be designed and mounted in such a way that its operation and detection functions are not impaired by head wind and/or true wind up to 100 knots and roll and/or pitch angles up to +/-10° at a frequency of (0.2 Hz +/-20%).
Efficient cleaning devices for the sensor head/lens regardless of weather conditions should be provided.
Its performance data should not be impaired by vibration occurring during normal ship's operation.
* IEC 945
