7
The required voltage for GRUNDFOS submersible
motors, measured at the motor terminals, is
–10%/+6% of the nominal voltage during continuous
operation (including variation in the supply voltage
and losses in cables).
If the booster module is connected to an electric
installation where an earth-leakage circuit breaker
(ELCB) is used as an additional protection, this cir-
cuit breaker must trip out when earth fault currents
with DC content (pulsating DC) occur.
The earth leakage circuit breaker must be marked
with the following symbol:
.
Supply voltage:
1 x 200-240 V –10%/+6%, 50/60 Hz, PE.
1 x 110-115 V –10%/+6%, 50/60 Hz, PE.
The current consumption can only be measured by
means of a true RMS instrument. If other instruments
are used, the value measured will differ from the
actual value.
The BMQE-NE booster modules can be connected
to a control box, type CU 300.
Note: The booster module must never be connected
to a capacitor or to another type of control box than
CU 300.
The booster module must never be connected to an
external frequency converter.
6.1 Motor protection
The motor incorporates thermal overload protection
and requires no additional motor protection.
6.2 Connection of motor
The motor incorporates a starter device and can
therefore be connected directly to the mains.
7. Liquid filling and module venting
The booster module(s) is/are filled with water/liquid
through the suction port of module 1, see fig. 3.
1. Slacken the air vent screw in the booster module.
2. Inject water/liquid until it starts running out of the
vent hole.
3. Tighten the air vent screw.
8. Operation
The booster modules must be started in the order
1-2-3-4 at intervals of 1 or 2 seconds.
The modules must be stopped in reverse order, i.e.
4-3-2-1, at the same intervals.
Module 1 is always the first module on the suction
side.
The start/stop intervals stated will reduce water ham-
mering in the system.
If water hammering is a problem in the modules dur-
ing stopping, it is recommended to install a dia-
phragm tank.
During operation, it must be checked that the inlet
pressure is as estimated.
When not being used, all modules should be filled
with water as all internal bearings are water lubri-
cated.
If the booster unit is taken out of operation for a long
period, the modules should be flushed through with
clean water. The modules are then left with clean
water until they are to be used again.
The total pressure and flow of modules connected in
series should never be changed by stopping one or
more of the modules. If different pressures or flows
are required, it is recommended to proceed as fol-
lows:
a) In the case of GRUNDFOS BMQ or BMQE-NE
booster modules installed in accordance with fig.
6, fit a bypass between two modules.
Stop the module(s) which is/are not required and
close the isolating valves on either side of the
module.
If the module(s) taken out of operation will not be
used for long periods, it is recommended to flush
this/these module(s) through with clean water.
If a module is taken out of operation as de-
scribed, it should always be the last one in the
series.
b) When a pressure reducing valve or a pressure
relief valve is fitted to the discharge pipe, the fol-
lowing minimum flows must be ensured at all
times:
• at 40°C: 0.8 m³/h (104°F: 3.5 US GPM).
• at 25°C: 0.5 m³/h (77°F: 2.2 US GPM).
Please note that the minimum flows stated do not
ensure optimum conditions and should be avoid-
ed, see section 8.1 Limitations to operation.
Furthermore, the operating pressure and the
maximum inlet pressure in sleeves must not ex-
ceed the values stated in section 8.1 Limitations
to operation.
If there is any danger of the modules running
against a closed discharge valve, a minimum liq-
uid flow through the pump should be ensured
(see above).
Furthermore, the liquid temperature must not ex-
ceed the values stated in section 8.1 Limitations
to operation.
If a module of a booster unit in series in a system
with two or more series connected in parallel without
bypass fails, the whole booster unit in question must
be switched off, because all modules connected in
series must develop the same pressure. Otherwise,
the module that develops a too low pressure will stop
and the next motors in the series will burn because
of insufficient cooling.
The booster module is not allowed to run
against a closed discharge valve as this
will cause an increase in temperature/for-
mation of steam in the pump which may
cause damage to the pump and the motor.
If there is any danger of the module run-
ning against a closed discharge valve, a
minimum liquid flow through the pump
should be ensured by connecting a by-
pass/a drain to the discharge pipe. The
drain can for instance be connected to a
tank.