HYDAC HMG 3000 - Manual (Page 20)

HMG 3000 Page 20
Edition 11/2007 - V02 R01-S02 Stock no.: 669712
Example:
For both 100 bar pressure transmitters there is a differential measurement range of
-10 – +10 bar, in other words a measurement margin of 20 bar. The accuracy of
≤±0.1%
refers to this measurement margin. The pressure differential can therefore be measured with
an accuracy of
≤±0.02 bar.
To measure a pressure differential, select
the item Pressure differential dP. Then you
find an item Organise curves. Here you can
plot up to 3 curves for 3 pressure transmitter
pairs. If a curve for a pressure transmitter
combination already exists, you can quit the
menu again by selecting Back or the Esc
key. The HMG 3000 automatically selects
the appropriate curve. If you quit the menu
and the HMG 3000 detects that no curve
exists for this combination, you will get the
message shown on the right. You can now,
with less accuracy, measure the differential
or you call the menu item again to record a
new curve under Organise curves.
Upon selecting Organise curves, a screen
appears which allows you to record a new
curve, or you see information on curves
which already exist. At this point you can
also delete existing curves if they are no
longer required. If curve 1 already exists,
navigate to this field and press the OK key.
You can now, for example, select
Characteristic
curve 2, Not available and
then record a curve. To record the curve you
must connect both pressure transmitters to
the HMG 3000 at channel A and channel B.
When doing this, identify which pressure
transmitter has been connected to channel A
and which to channel B, since the pressure
transmitters must be re-connected in the
same way later when taking measurements.