Dutypoint VT Booster Set, Руководство по эксплуатации и обслуживанию, Страница: 39 / 123

English (GB)
G
10
7.3 Single-phase connection
Fig. 16
Connection, "low voltage", 0.37 - 0.75 kW
Fig. 17
Connection, "high voltage", 0.37 - 0.75 kW
Fig. 18
Connection, "low voltage", 1.1 - 2.2 kW
Fig. 19
Connection, "high voltage", 1.1 - 2.2 kW
Single-phase Grundfos motors incorporate a thermal switch and
require no additional motor protection.
7.4 Terminal box position
The terminal box can be turned to four positions, in 90 ° steps.
Follow this procedure:
1. If necessary, remove the coupling guards. Do not remove the
coupling.
2. Remove the bolts securing the motor to the pump.
3. Turn the motor to the required position.
4. Replace and tighten the bolts.
5. Replace the coupling guards.
Carry out the electrical connection as shown in the diagram
inside the terminal box cover.
7.5 Frequency converter operation
Motors supplied by Grundfos
All three-phase motors supplied by Grundfos can be connected to
a frequency converter. The frequency converter must be set to
variable torque.
Depending on the frequency converter type, this may cause
increased acoustic noise from the motor. Furthermore, it may
cause the motor to be exposed to detrimental voltage peaks.
We recommend to protect all other motors against voltage peaks
higher than 1200 V by 2000 V/
μ
sec.
The above disturbances, i.e. both increased acoustic noise and
detrimental voltage peaks, can be eliminated by fitting an LC filter
between the frequency converter and the motor.
For further information, please contact the frequency converter or
motor supplier.
Other motor makes than those supplied by Grundfos
Please contact Grundfos or the motor manufacturer.
8. Start-up
Follow the instructions on page 28 .
CR, CRI, CRN 1s to 5
For these pumps, we advise you to open the bypass valve during
start-up, see fig.
20 for bypass valve location. The bypass valve
connects the suction and discharge sides of the pump, thus
making the filling procedure easier. Close the bypass valve again
when the operation is stable.
When pumping liquids containing air, we advise you to leave the
bypass valve open if the operating pressure is lower than 6 bar.
Close the bypass valve if the operating pressure constantly
exceeds 6 bar. Otherwise the material at the opening will be worn
because of the high liquid velocity.
Mains supply [V]
"Low voltage" "High voltage"
50 Hz
220-230 / 240
T
M
04
16
93
10
08
TM
04
16
94
10
08
TM
04
03
45
06
08
TM
04 034
4 060
8
Caution
Grundfos motors, types MG 71 and MG 80, for
supply voltages up to and including 440 V
without phase insulation (see motor nameplate),
must be protected against voltage peaks above
650 V (peak value) between the supply terminals.
Caution
Do not start the pump until it has been filled with
liquid and vented. If the pump runs dry, the pump
bearings and the shaft seal may be damaged.
Warning
Pay attention to the direction of the vent hole and
take care to ensure that the escaping water does
not cause injury to persons or damage to the
motor or other components.
In hot-water installations, pay special attention to
the risk of injury caused by scalding hot water.