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Connection diagrams: connection of the power supply cable and of the terminals on the terminal strip
4.10.1 - Plug fans
Plug fans are fans without a scroll that are directly driven by
the motor. To get the correct operating point for this type of
fan a frequency converter is required. The maximum
frequency at which the plug fan can rotate depends on the
motor/impeller assembly and should normally be higher
than 50 Hz. The maximum frequency is given on the fan
name plate.
Plug fans are equipped with a pressure measurement point
in the intake cone of the fan. By measuring the pressure
drop between the pressure for the fan and the pressure in
the intake cone the actual air flow can be calculated using
the following formula: V = k ·√∆p
st
Where
V = actual air flow rate in m3/h
k = specific fan coefficient
∆p
st
= pressure differential cone/air intake section in Pa
