HYDAC HMG 3000 - Manual (Page 23)

HMG 3000 Page 23
Edition 11/2007 - V02 R01-S02 Stock no.: 669712
Input channels I and J are for digital signals.
As the input signal you can choose between
Count pulses
and Frequency signal. There
are many possibilities for this, e.g. speed
sensors, proximity switches, pulse
generators, flow rate measuring instruments
with a frequency signal, HYDAC HDS 1000,
to name only a few. As in the case of the
analog sensor inputs, settings can be
manually entered for the input signal, unit of
measurement and decimal format.
In addition to these settings, a factor has
to be entered which is required for
conversion to the desired unit of
measurement.
Another special feature is the inputting of the
Upper measurem. range
. Frequencies of up
to 30000 Hz can be measured on channels I
and J, consequently a scale from 0 to 30000
is possible in the graphical display. If, for
example, you record a speed of up to 1450
rpm, an awkward Y-axis scale will result in
the graph. If you enter "1500" as the Upper
measurement range
for this speed
measurement, for example, the Y-axis in the
graph will be scaled from 0 to 1500 rpm.
In this case entering the upper measurement range is just a means of limiting the scale of the
Y-axis in the graphical display. You should set this value as close as possible to that of the
expected measured value in order to get the best possible graphical display.
If measured values exist which are larger than the upper measurement range, these are not
lost. The scale of the Y-axis can be changed again in the graph at any time later on.
N.B.
The measurement range of the frequency entries is 1 Hz to 30000 Hz. If, for example, the
rpm of a motor is recorded and this motor stops abruptly, the last rpm can still show in the
display for up to 2 seconds, depending on the measurement system, before 0 is displayed.