Checking the environmental conditions in the sonar room
It is important that the sonar room is kept clean and dry. The system units must not be exposed to excessive temperatures, moisture or humidity. Such conditions can cause corrosive attacks and subsequent failures to the electronic circuitry.
Prerequisites
The following specific instruments are required for this task:
•  Thermometer
•  Hygrometer
Procedure
1 Make sure that the compartment ("sonar room") is clean and dry.
2 Make sure that the ambient temperature in the room meets the environmental specifications.
a Make sure that the room is provided with ample ventilation to prevent system units from overheating.
b Write down the type of ventilation system that is installed.
c Make sure that the ambient temperature of the room is monitored.
d Measure the ambient temperature in the room when the SU90 system is turned off.
e Record the value in the result table.
3 Make sure that the relative humidity in the room meets the environmental specifications.
a Measure the relative humidity in the room.
b Record the value in the result table.
4 30 minutes after the SU90 system was turned on and put to normal operation, measure the relative humidity one more time.
Record the value in the result table.
5 30 minutes after the SU90 system was turned on and put to normal operation, measure the relative humidity one more time.
Record the value in the result table.
6 Make sure that neither the room itself nor any of the system units have been subjected to corrosive attacks.
Result
  The SU90 system is turned off. The SU90 system is turned on.
Ambient temperature:  

 
Relative humidity: