8 Commissioning/Shutdown
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PumpDrive 2
The diagram shows the setpoint compensation curve (solid line) as a function of the
flow rate and relevant parameters. The compensated setpoint (3) is the sum of the
flow rate independent setpoint (1) and setpoint compensation (2). The flow rate
independent setpoint (1) is configured as described in (ðSection8.6,Page70) .
Setpoint compensation (2) starts at flow rate Q = 0 and achieves the value defined
under Setpoint Compensation (3-9-3-4) at the Dyn Press Comp Q Data Point (3-9-3-2)
flow rate. Setpoint compensation also continues along the parabola shown. A
minimum pressure increase as for dynamic pressure compensation with pressure
sensors is not possible.
NOTE
To facilitate sensorless differential pressure control, all parameters of the pump
characteristic curves (3-4-1, 3-4-3-1 to 3-4-3-22) must be entered.
Table73: Parameters for sensorless pressure/differential pressure control with dynamic pressure compensation
Parameter Description Possible settings Factory setting
3-6-1 Type of Control
Selecting the control method. The
controller is deactivated when OFF (Open-
loop Control) is selected.
Differential pressure (sensorless) Dependent on pump
3-9-3-1 Dynamic Pressure Compensation Method
Selecting the dynamic differential pressure
compensation method (DFS). Dynamic
pressure compensation based on speed
can only be used for systems without a
geodetic head (e.g. in closed systems).
Flow Rate OFF
3-9-3-2 Dyn Press Comp Q Data Point
The setpoint compensation value is
reached at this point. Beyond that, the
setpoint is further increased with respect to
the specified value.
Minimum to maximum flow rate 0 m³/h
3-9-3-4 Setpoint compensation
Configurable setpoint compensation at
data point 3-9-3-2 or 3-9-3-3
Minimum to maximum limit of
measuring range
0 %
8.8.4.2 Sleep mode
NOTE
In sleep mode, PumpDrive may start up without any warning if the actual value
exceeds the Maximum Control Deviation for Restart (3-9-4-5).
Sleep mode can be used for the following control tasks:
▪ Controlling the discharge pressure or differential pressure (including sensorless
control)
▪ Controlling the temperature for heating
▪ Controlling the level for filling
Sleep mode allows the single or multiple pump system to be started and stopped as
required. If sleep mode is activated, the frequency inverter stops the pump in the
case of low flow rates, i.e. should the low flow limit be continuously undershot
(3-4-3-30) or the stop speed be continuously undershot (3-9-8-4). In pressure control
applications, an accumulator can be filled during brief operation with an increased
setpoint (3-9-4-2) prior to stopping. If a drop in pressure and, thus, a flow rate
requirement are detected, the pump restarts.
Sleep mode only takes effect in closed-loop control mode. In multiple pump systems,
sleep mode only takes effect if just one pump is running. Sleep mode is activated via
parameter (3-9-4-1).
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