- 13.2 Hz and 100 Hz with a constant maximum acceleration of 7 m/s2.
The frequency sweep rate shall be slow enough to allow the detection of resonances in any part of the EUT.
A resonance search shall be carried out during the vibration test. If any resonance of the EUT has Q > 5 measured relative to the base of the vibration table, the EUT shall be subjected to a vibration endurance test at each resonance frequency at the vibration level specified in the test with a duration of 2 h. If no resonance with Q ≧ 5 occurs, the endurance test shall be carried out at one single observed frequency. If no resonance occurred, the endurance test shall be carried out at a frequency of 30 Hz.
Performance checks shall be carried out at least once during each endurance test period, and once before the end of each endurance test period.
The procedure shall be repeated with vibration in each of two mutually perpendicular directions in the horizontal plane.
After conducting the vibration test the EUT shall be inspected for any mechanical deterioration.
8.2.3 Result required
The EUT shall meet the requirements of the performance check.
There shall be no visible harmful deterioration of the EUT.
8.3 Storage test for exposed equipment
According to IEC 60945 8.2.1 for exposed equipment
8.3.1 Objective
To demonstrate that the EUT can be stored at high ambient temperature and still be operational afterwards. A temperature of +70 ℃ is the maximum likely to be encountered in enclosed spaces on ships and in equipments exposed to the full effects of solar radiation in ports.
8.3.2 Method of measurement
The EUT shall be placed in a chamber at normal room temperature and relative humidity. The temperature shall then be raised and maintained at + 70 ℃ ± 3 ℃ for a period of 10h to 16h
At the end of test, the EUT shall be returned to normal environmental conditions and then the EUT shall be subjected to the performance check in subclause 7.2.7
At the end of the test, the EUT shall be returned to normal environmental conditions or to those required at the start of the next test.
8.3.3 Result required
The EUT shall meet the requirements of the performance check
8.4 Dry heat test for protected and exposed equipment
8.4.1 Objective
To demonstrate that the EUT can operate at high ambient temperature and through the temperature changes. The reasonable maximum air temperature likely to be encountered over the sea is + 32 ℃ and the maximum solar gain is + 23 ℃ giving + 55 ℃ as the maximum temperature likely to be encountered by ships at sea.
