8.2 Controlled operation (closed loop)
CUE
Δp
CUE
Δp
CUE
Δp
CUE
CUE
L
L
CUE
16
Proportional
differential
pressure.
The differential
pressure is reduced
at falling flow rate
and increased at
rising flow rate.
Constant
differential
pressure, pump.
The differential
pressure is kept
constant,
independently of
the flow rate.
Constant
differential
pressure, system.
The differential
pressure is kept
constant,
independently of
the flow rate.
Constant pressure.
The pressure is
kept constant,
independently of
p
the flow rate.
Constant pressure
with stop function.
The outlet pressure
is kept constant at
high flow rate. On/
p
off operation at low
flow rate.
Constant level.
CUE
The liquid level is
kept constant,
independently of
the flow rate.
Constant level with
stop function.
CUE
The liquid level is
kept constant at
high flow rate.
On/off operation at
low flow rate.
Constant flow rate.
The flow rate is
kept constant,
independently of
Q
the head.
Constant
temperature.
CUE
The liquid
temperature is kept
constant,
t
independently of
the flow rate.