Setup in a plant room
If the load bank is setup in a plant room you will need to pay particular attention to the
airflow requirements of the unit. The temperature of the surrounding air must not rise
above the maximum rated ambient temperature of the load bank (40°C is standard) and
steps should be taken to prevent re-circulation of the discharge air.
You must take into account the requirements of any other equipment (heating plant,
generating sets, compressors, or another load bank) that may also require a supply of
cooling air. In these cases the total air requirement of all the plant must be added together
to arrive at the required fresh airflow.
The air inlet and air outlet of the load bank must be in the same room, or space.
Inlet
The free area of any inlet grille or opening into the plant room should be at least twice
the area of the load bank air outlet. If other plant in the same plant room requires air,
then the size should be such that the maximum air inlet velocity is below 3m/sec. This
should ensure that the depression within the plant room would always be less than 10Pa,
relative to the outside environment. The distance from the fan inlet to a blank face of a
wall or panel, square to the fan centre line, should be not less than 1m, or one fan diameter,
whichever is the greater.
Attenuators incorporated in the plant room inlet grilles should be sized for a maximum
pressure drop of 10Pa.
Outlet
The outlet opening must have a total free area of twice that of the load bank air outlet, plus
whatever is required for any additional plant.
Wind effects
The load bank must be protected from the effects of the wind, which in some circumstances
could defeat the fan. The inlet and outlet grilles or louvres should preferably be on the
same side of the building. The effect of natural wind is then cancelled out, regardless of
its direction. Other arrangements need careful attention, combined with detailed site and
local knowledge to ensure satisfactory operation in all expected weather conditions.
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Avoiding hot air re-circulation
To reduce the risk of hot air re-circulation place air inlets at low level and air outlets at high
level. If this is not possible the inlets and outlets should be spaced well apart. Inlet and
outlet louvres on the same level should have a clear space between them of at least three
times the width of the largest opening. Strategically placed barriers and screens can help
to separate the two air-streams.
Careful consideration should be given to the likely effect of nearby buildings, walls or even
parked vehicles, which could seriously disrupt the free escape of hot air, and result in hot
air re-circulation.
Other nearby air handling plant can also interfere with the airflow to, or from, the load bank.
Equipment should be spaced well apart and positioned so that their airflows complement
each other rather than compete.
When multiple load banks are being used it is important to ensure that the hot air from one
load bank does not exhaust directly or indirectly on to any other load bank.
Packaging
Before starting setup remove all packaging. Dispose of it in the appropriate way.
Chapter Two
Load Bank Setup
