Nautel NX100, Руководство по предварительной установке

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NX100 Pre-installation Manual Cooling requirements
Issue 3.2 2017-03-31 Page 4-3
Cooling
Do not allow the transmitter room ambient air temperature to exceed 50°C (122°F) at sea level.
Cooler temperatures are recommended in order to improve the reliability of the transmitter. At higher
altitudes, derate the maximum inlet air temperature as follows:
• De-rate the ambient temperature 3ºC (5.4°F) per 500 m – or 2ºC (3.6°F) per 1,000
feet – above sea level.
Example:
At 1600 m (1 mile) above sea level, maximum ambient temperature should not
exceed 40.4ºC (104.7°F).
Note:
Ensure hot air from the transmitter is not drawn back into the transmitter’s cool air intake.
Cooling plant requirements
In an NX100 system, heat is generated by both the transmitter and the transformer, and each may be
cooled separately. The transmitter’s efficiency is typically 92% and the transformer’s efficiency is 98%.
Calculate the power dissipated by the transmitter using the following equation:
Where ............ is the transmitter’s efficiency and P
out
is the transmitter’s average output power.
Calculate the power dissipated by the power transformer using the following equation:
Where ............ is the transformer’s efficiency. For continuous tone modulation, calculate the average
output power of the transmitter using the following equation:
Where m is the modulation depth and P
c
is the transmitter’s output carrier power.