Grundfos Hydro 2000 F, Инструкция по установке и эксплуатации

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12. Glossary
Actual value
Actual value is the measured value.
Analog input
Analog signals from transmitters can be connected to the analog
inputs of PFU 2000 or PCU 2000.
BUS
The GRUNDFOS BUS enables communication among the units
connected to the GRUNDFOS Pump Management System 2000.
The communication (RS-485) is performed according to the
GRUNDFOS BUS protocol.
Closed-loop control
Closed loop is the designation of a control system with a feed-
back signal from a transmitter.
Control
The controller compares a signal from an external transmitter
(actual value) with a setpoint.
The setpoint is an indication of a required state. The transmitter
constantly registers whether this required state is maintained. On
the basis of the above-mentioned comparison, the controller con-
tinuously adapts pump speed so as to automatically make system
performance result in the required state.
Default value
The default value is the factory-set value/parameter, i.e. the
value/parameter which will appear if no other value is set. This is
for instance the case in connection with presettings.
Differential pressure
Differential pressure is the pressure difference between two
measuring points, e.g. between suction and discharge ports of
the pump.
Differential temperature
Differential temperature is the temperature difference between
two measuring points, e.g. flow and return pipes.
Digital input
Digital signals from signal transmitters can be connected to the
digital inputs of the PFU 2000.
Display overview
A display overview is a total overview of the displays which may
appear in a menu with a given presetting.
Flow
Flow is the quantity of pumped liquid which passes through
pumps/a zone within a certain period, e.g. indicated in [m³/h].
Head
Head designates the pressure increase imparted to the liquid by
the pump, e.g. indicated in [m].
“Local” operation
When the pumps/zone are not controlled via a PMU 2000 but ac-
cording to the settings made via the PFU 2000, the operating
mode is referred to as “local”.
“Max.” operation
When the pumps/zone are controlled via a PMU 2000 or via the
PFU 2000, it is possible to set the pumps/zone to “Max.” opera-
tion. The pumps will run at maximum speed (irrespective of exter-
nal signals).
Menu
Menu is the designation of one of six different groups of displays
in the PMU 2000. Settings and readings are made in the menus,
which consist of a number of displays.
Open-loop control
Open loop is the designation of a control system without feed-
back signal from a transmitter.
PCU 2000
The Pump Communication Unit 2000 is used for communication
between the GRUNDFOS BUS and external control and monitor-
ing systems.
PFU 2000
The Pump Functional Unit 2000 is used to control and monitor
pumping systems.
PMU 2000
The Pump Management Unit 2000 is used to monitor and opti-
mize pumping systems.
Pre-pressure
Pre-pressure is the pressure which can be measured immediately
before the booster set/pump.
Progressive pressure
Progressive pressure means that the pressure in the system
rises/falls proportionally to the flow (friction loss compensation).
Proportional pressure
See “Progressive pressure”.
Temperature influence
Temperature influence means that the setpoint is influenced by
the actual liquid temperature. The liquid temperature is continu-
ously measured and the setpoint automatically adjusted accord-
ing to this measurement and a setpoint influence table.
Zone
A zone is a closed hydraulic system in which all pumps have
common suction and discharge pipes.