DAB MCE-30/P, Instruction For Installation And Maintenance

Page: 101 / 600

ENGLISH
97
6.6.3 T2: Shutdown delay
This sets the delay after which the inverter shuts down after shutdown conditions have been reached:
system pressure and flow at minimum values.
T2 can be set between 5 and 120 s. The default setting is 10 s.
6.6.4 GP: Proportional gain coefficient
The proportional gain should generally be increased for elastic systems (wide and PVC pipelines) and
reduced in the case of rigid systems (narrow and steel pipelines).
To maintain constant system pressure, the inverter performs a PI check on the measured pressure error. On
the basis of this error, the inverter calculates the power to supply to the electric pump. The behaviour of this
check depends on the set parameters GP and GI. To meet the different requirements of the various types of
hydraulic systems where the system may operate, the inverter enables the selection of parameters that are
different from the default settings.
On virtually all systems, the factory setting of parameters GP and GI
are optimal.
However, in the event of problems with regulation, these settings may be modified as required.
6.6.5 GI: Integral gain coefficient
In the event of significant pressure drops on sudden increases in flow, or a slow system response, increase
the value of GI. Otherwise, in the event of pressure oscillations around the setpoint, reduce the value of GI.
NOTE: A typical example in which the value of GI should be reduced is that in which the inverter is located
far from the electric pump. This distance causes hydraulic elasticity which influences control of PI and
therefore pressure regulation.
IMPORTANT: To obtain satisfactory pressure settings, both values GP and GI should be adjusted.
6.6.6 FS: Maximum rotation frequency
This sets the maximum pump rotation frequency.
This sets a maximum rpm limit and can be set between FN and FN - 20%.
FS, in any conditions of regulation, ensures that the electric pump is never controlled at a frequency higher
than the set value.
FS can be automatically reconfigured following modifications to FN, when the above ratio is not verified (e.g.
if the value of FS is less than FN - 20%, FS will be reset to FN - 20%).
6.6.7 FL: Minimum rotation frequency
FL is used to set the minimum pump rotation frequency. The minimum admissible value is 0 [Hz], and the
maximum is 80% of FN; for example, if FN = 50 [Hz], FL can be set between 0 and 40[Hz].
FL can be automatically reconfigured following modifications to FN, when the above ratio is not verified (e.g.
if the value of FL is greater than 80% of the set FN value, FL will be reset to 80% of FN).