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4 - The blower delivers a fixed air speed.
The air velocity is calculated by
controlling the air flow as in operating mode 3. In this operating mode, the
pipe diameter must be specified, to calculate the air velocity.
It is rare that the blower's air speed is more than 60 m/s, which is why it is
set to the default value on the air speed scale, as seen on the right side of
the screen. If you want to change the value, press the existing value and
enter a new value.
It is possible to select air speed in m/s or in ft/min. If the pressure in ft/min
is selected, the unit on the scale changes to ft/min. 60 m/s is approx. 9.842
ft/min.
It is possible to change the scale to other values lower than 60 m/s, which
is the maximum on the scale. This can provide a better understanding for
the operator, as the blower may not necessarily achieve the maximum
pressure, since this depends on the installation.
If the air speed is desired in a pipe diameter other than Ø350 (as on the
blower's inlet and outlet), this can be corrected to the right of the pipe icon.
If the % button is selected, the air velocity scale will change to a % scale.
Another max % value can then be entered.
An extra line now appears at the bottom of the screen, where the ratio be-
tween 100% and the air speed in m/s / ft/min must be defined.
Both with control with pressure (Pressure), Volume or flow (Air speed) it is
possible to select Feedback Source. In this screen, a curve is seen over the
input signal, which here must be 0 at 0V and max. at 10V.
The max. value is specified in the field to the left, and the unit of measure
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ment in the field to the right.
First select whether the signal from the transducer is a 0-10 volt signal or a
4-20 mA signal. Next, select which value the maximum output of the pres-
sure transducer represents, here 10 volts corresponds to 40 InWG. It is
possible to switch between InWG and kPa.
Pressing the icon Wire diagram, a diagram appears, showing the connec-
tion of a pressure- or flow transducer.
When controlling pressure, flow or air speed, it is possible to choose a dif
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ferent type of differential pressure transducer than the one supplied in the
standard kit from Kongskilde.
