Grundfos Control MPC Montage- Und Betriebsanleitung Seite 44

Related information
8.6.24 Stop function (4.3.1)
8.6.25 Pilot pump (4.3.2)
8.6.26 Soft pressure build-up (4.3.3)
8.6.27 Emergency run (4.3.5)
8.6.28 Digital inputs (4.3.7)
8.6.30 Analog inputs (4.3.8)
8.6.33 Digital outputs (4.3.9)
8.6.35 Analog outputs (4.3.10)
8.6.37 Counter inputs (4.3.11)
8.6.38 Min., max. and user-defined duty (4.3.14)
8.6.42 Pilot pump curve data (4.3.18)
8.6.43 Pump curve data (4.3.19)
8.6.45 Control source (4.3.20)
8.6.46 Fixed inlet pressure (4.3.22)
8.6.47 Flow estimation (4.3.23)
8.6.48 Reduced operation (4.3.24)
8.6.49 Multisensor settings (4.3.25)
44
8.6.24 Stop function (4.3.1)
Stop function
Description
The function is typically used in constant-pressure applications and
allows you to stop the last pump if there is no or a very small
consumption.
Purpose of the function:
• to save energy
• to prevent heating of shaft seal faces due to increased
mechanical friction as a result of reduced cooling by the pumped
liquid
• to prevent heating of the pumped liquid.
When a pilot pump is connected to the system, the stop
function parameters will be valid for the pilot pump and not
the main pump as the pilot pump will be the last pump in
operation.
The description of the stop function applies to all systems with
variable-speed pumps.
H
Q
Start/stop band
Pos. Description
A On/off control
B Normal operation
C Start/stop band
When the stop function is enabled, the operation is continuously
monitored to detect a low flow rate. When CU 352 detects no
or a low flow rate (Q lower than Q
pressure operation to on/off control of the last pump in operation.
Before stopping, the pump increases the pressure to a value
corresponding to H plus (distribution above setpoint / 100) x start/
set
stop band. The pump is restarted when the pressure is H
(100-distribution above setpoint) / 100 × start/stop band. The start/
stop band can be distributed around the setpoint.
), it changes from constant-
min
minus
set