Pipe Connection; Operating Conditions; Inlet Pressure; Discharge Pressure - Grundfos BMP Series Installation And Operating Instructions Manual

7. Pipe connection

The BMP pump has a threaded connection on the suction and
discharge sides of the pump, see pages
Note: BMP-R pumps with flows ranging from 5.1 to 10.2 m
fitted with clamp liners for Victaulic/PJE clamp couplings on the
suction and discharge sides.
Note: It is recommended to use flexible high-pressure hoses.
If the suction pipe connected to the pump suction port (I) is
disconnected from the water supply, the pump will be emptied of
water. When the pump is to be started again, the starting
procedure in section 10. must be followed carefully.

8. Operating conditions

8.1 Inlet pressure

0 to 4 bar (1 bar abs. to 5 bar abs.).
It is recommended to install a low-pressure switch after the
prefilter. The low-pressure switch must switch off the electricity
supply to the pump if the inlet pressure falls outside the range
from 0 to 4 bar.

8.2 Discharge pressure

Warning
To avoid any damage to the system, a pressure relief
valve must be fitted on the discharge side.
The pressure relief valve setting must not exceed the
maximum permissible discharge pressure by more
than 5 %, see pump nameplate.

9. Electrical connection

The electrical connection must be carried out by a qualified
electrician in accordance with local regulations.
Warning
Before removing the terminal box cover and before
any removal/dismantling of the pump, make sure that
the electricity supply has been switched off.
The pump must be connected to an external mains
switch with a minimum contact gap of 3 mm in all
poles.
The operating voltage and frequency are marked on the motor
nameplate. Make sure that the motor is suitable for the electricity
supply on which it will be used.
The motor must be connected to a motor starter.
Carry out the electrical connection as shown in the diagram
inside the terminal box cover.

9.1 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
operation with a constant torque.
Dependent on the frequency converter type, this may cause
increased acoustic noise from the motor. Furthermore, it may also
cause the motor to be exposed to detrimental voltage peaks.
Note: Grundfos motors type MG 90 (1.5 kW, 2-pole), for supply
voltages up to and including 440 V (see motor nameplate), must
be protected against voltage peaks higher than 650 V (peak
value) between the supply terminals.
It is recommended to protect all other motors against voltage
peaks higher than 850 V.
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 details, please contact your frequency converter or
motor supplier.
6
128 and 129.
3
/h are

9.2 Motor protection

The pump must be connected to an effective motor starter which
must protect the motor against damage from voltage drop, phase
failure, overload and a locked rotor.
9.2.1 Setting of motor starter
For cold motors, the tripping time for the motor starter must be
less than 10 seconds at 5 times the rated full-load current of the
motor.
To ensure the best protection of the motor, the setting of the
motor starter should be carried out as follows:
1. Set the starter overload to the rated full-load current (I
motor.
2. Start the pump and let it run for half an hour at normal
performance.
3. Slowly grade down the scale indicator until the motor starter
trips.
4. Increase the overload setting by 5 %, but not higher than the
full-load current (I ).
N
For motors wound for star-delta starting, the starter overload unit
should be set as described above, but the maximum setting must
not exceed the following:
Starter overload setting = Rated full-load current (I
In the case of frequency converter operation, follow the
manufacturer's instructions.

9.3 Generator operation

In the case of generator operation, contact Grundfos.

10. Start-up

Before the pump is installed in the piping system, this should be
flushed through with clean water to remove possible impurities
from pipes, hoses, etc.
1. Venting: Before starting the pump, slacken the vent plugs "A",
see fig. 4. When the water starts running out of the holes, the
pump has been filled with water. Retighten the plugs.
2. Direction of rotation: Start the pump (for 1 sec. only) and
check the direction of rotation. The correct direction of rotation
is stated on the pump nameplate. If necessary, interchange
any two of the incoming supply wires.
Note: The pump must not run dry.
3. Water supply: When the suction pipe has been connected to
the water supply or tank, start the pump with an open
discharge port (O).
4. Prefilter: It is recommended to replace the filter element after
1 to 10 hours of operation after the first start-up.
A
Fig. 4 Vent plugs

11. Operation

During operation the pump must always be connected to the
water supply.
Note: Dry running will damage the pump.

11.1 Operation settings

The flow and discharge pressure of the pump should always be
kept within the ranges for which the system was originally
designed.
If the system requires flows and pressures outside the design
range, please contact Grundfos.
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N
) x 0.58.
N
A
A