inspection is made of the installation cooling system. The amplifier should be left for 20 minutes
e sections 5 and 6).
e air exhaust.
•
event hot exhaust air from re-circulating to the cooling
n designing common ducting systems for multiple amplifiers.
e
3.3.2
ction 3.1). The cowl can be turned through 180° for
lternative mounting configurations. The cowl is designed to avoid driving rain entering the unit if a
ed.
•
•
re restrictive to airflow.
•
•
Do not use ducting adaptors that reduce the internal cross-sectional area of the ducting.
ct systems, install additional external fans to provide adequate
3.3.3 Equ m
All equ
light cases, roof mount enclosures, cabins and air-
con
•
Maintain an adequate supply of air to the inlet; a 250 cm (39 in
2
) unimpeded aperture should
be provided into any enclosure for each Stellar amplifier.
nation of cooling air should be ideally be common, to avoid back-
Housings that are exposed to environmental wind effects should use a common face inlet for
st vents should be of a design that prevents direct
environmental wind effects, whilst avoiding creating additional restriction to airflow.
before any attempt is made to restart.
Following an over-temperature condition, the TWT COLLECTOR TOO HOT or CASE TOO HOT fault
conditions are set. These conditions can be monitored via the user interface or accessed through the
serial communications port (se
When deciding on the location of the amplifier the following points should be observed:
•
It is important not to obstruct the air inlet or th
In any system, it is mandatory to pr
inlet, otherwise the air temperature will increase, resulting in potential thermal runaway. This
is a prime consideration whe
•
In any other instance, if there is significant additional obstruction to the airflow, then it may b
necessary to provide externally forced or cooled air to the amplifier.
Ducting
Considerations
The amplifier is provided as standard with one air cowl, the normal orientation of which is pointing
owards the base of the amplifier (see se
t
a
secondary cover is not us
Any ducting connected to the air inlet or exhaust will create additional back-pressure, reduce the
airflow and increase the internal temperature of the amplifier. Additional ducting should be avoided if
possible, but if it is essential for the application then:
•
Keep ducting lengths to a minimum. Check the amplifier maximum operating temperature de-
rating for the length of duct required.
•
Route ducting directly, avoid sharp bends and ensure that the minimum bend radius is three
times the ducting diameter.
Use the largest cross-sectional area of ducting possible.
Use smooth walled ducting and avoid corrugated ducting, as it is mo
Transitions in ducting sizes should be smooth, so avoid step changes.
If the installation dictates restrictive du
airflow and counteract the effects of ducting. The additional fans should be installed on the air input to
the amplifier, where the air is at its coolest.
ip ent
Housing
ipment housings, including basic f
ditioned rooms, have common cooling system design requirements:
2
•
The local source and desti
pressure caused by differential pressure effects.
•
exhaust vents, to avoid back-pressure caused by differential wind effects.
•
Terminations of inlet and exhau
•
If a sealed cooling system with re-circulating air-conditioners is used, an over temperature
alarm should be fitted to the cabin to detect air conditioner failures.
© e2v technologies (uk) limited 2010
DAS768892AA
Version
1,
page
12
