IMP Pumps ECL - Handbuch (Seite 22)

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GB
- d) The lock valves on the piping on the
pressure side of the pump must be
closed.
- The protection of all rotating parts must be
implemented as required by the safety at
work regulations.
- When starting the pump, the lock valve
on the pressure side of the pump must be
opened slowly, after the electric motor has
reached the highest rotations.
- With the increase of the medium tempera-
ture and possible leakage of the medium
at the contacts protected by seals, care
should be taken that the screws are prop-
erly fastened, and in the case of excessive
dripping, the screws should be tightened.
- The shut-down of the pump should also be
implemented with certain rules. Before shut-
down of the pipe, all valves on the pressure
side of the pump should be closed, this is
essential in avoiding the occurrence of back
pressure. It is also extremely important dur-
ing shut-down that the lock valves on the
suction piping are open.
- A higher temperature can be dangerous
during dismantling, so the flow of a cooler
medium must be assured before stopping
the pump. The electric motor must be
stopped steadily without any forcible
interventions to the pump.
- Extremely low temperatures of the medium
must be prevented in the system due to
potential freezing, including releasing the
medium from the system.
B) Functioning of electronically
regulated pumps
The main function of the electronically regulated
ECL pumps is assuring different flows at same
pressure heights. Such conditions are char-
acteristic for systems with inbuilt thermostatic
valves were requirements frequently change.
Changes are sensed by a sensor built onto the
pump, which then gives the electric values to
the frequency converter. The frequency con-
verter then suitably controls the electric motor
rotations. This is how we achieve the auto-
matic adaptation of the pump to the hydraulic
conditions of the system. The power savings
are significant. With this, we save on electrical
energy, reduce the noise level of the device,
and ensure optimal operation of the heating
and cooling devices with a simple execution of
the hydraulic system.
C) Drive features
The electric motor’s drive behaviour of induc-
tion (asynchronous) motors with a short cir-
cuit cage, which are controlled by frequency
converters, is for dynamic and static regimes
dependent on the characteristics of the con-
verter, the characteristics of the electric mo-
tor, and the characteristics of the pump.
- 1. Dynamic operation regime
Here we include START-UP, BRAKING,
RETURNING, and STOPPING the DRIVE.
The user defines the desired behaviour of the
drive with the help of closing the valves and
with the choice of U/f characteristics on the
frequency converter (pump manufacturer’s
settings with frequency regulation).
- 2. Static operation regime
With a static operation regime, the standard
induction electric motor regulated with a
frequency converter can be continuously
loaded with the given momentum in the field
of rotation speed at 50% of the given rotation
speed that corresponds to a frequency from
25 to 50 Hz.
At a frequency smaller than 25 Hz, the electric
motor ventilation is significantly reduced, and
therefore, the electric motor must not be load-
ed with the given momentum, but with lower
values, which is the case with the drive of fre-
quency regulated pumps. The factory settings
contain the upper and lower frequency on the
converter in the pump drive before start-up.
D) Starting the pump by frequency
regulation
For a fast and successful start-up, quality
preparations should be completed:
- Completing the wiring plan with the
conductor and cable legend.
- Connecting the electric motor and
frequency converter.
- Turning on the power.
- Parameter settings (factory settings), with
the help of the attached instructions, a user
can change the parameters unaided.
E) Description of functions for regulation
RESEt:
Immediately after connecting the frequency
converter to the network, some of the