Grundfos BM 125, Installation And Operating Instructions Manual

Page: 5 / 18

English (GB)
5
7. Electrical connection
The electrical connection must be carried out by an authorised
electrician in accordance with local regulations.
The required voltage quality measured at the module terminals is
- 10 %/+ 6 % of the rated voltage during continuous operation
(including variation in the supply voltage and losses in cables).
Check that there is voltage symmetry in the power supply lines,
i.e. approximately same difference of voltage between the
individual phases. See also section
15. Checking of motor and
cable
, point 1.
In order that the modules meet the EC EMC Directive (2004/108/
EC), a 0.47
μ
F capacitor (in accordance with IEC 384-14) must
always be connected over the two phases to which the
temperature transmitter is connected. See fig.
11 .
Fig. 11 Electrical connection
The electrical connections must be made close to the flange (fig.
12 ), either by means of a terminal box (figures 13 and 14 ) or a
cable termination kit.
Fig. 12 BM/BMhp with terminal box
Fig. 13 Wiring diagram, DOL connection
Fig. 14 Wiring diagram, star-delta connection
7.1 Frequency converter operation
Grundfos motors
Three-phase Grundfos MS and MMS motors can be connected to
a frequency converter.
If a frequency converter is to be used for booster modules
connected in series, it must be connected to the last module in
the flow direction.
We recommend Grundfos CUE. The CUE is a series of frequency
converters designed for speed control of a wide range of
Grundfos products, for example BM and BMhp.
During frequency converter operation, it is not advisable to run
the motor at a frequency higher than the rated frequency (50 or
60 Hz). In connection with pump operation, it is important never to
reduce the frequency, and consequently the speed, to such a
level that the necessary flow of cooling liquid past the motor is no
longer ensured.
The permissible frequency ranges are 30-50 Hz and 30-60 Hz,
respectively.
During start, the maximum acceleration time from 0 to 30 Hz is 3
seconds.
During stop, the maximum deceleration time from 30 to 0 Hz is 3
seconds.
Depending on the frequency converter type, it may expose the
motor to detrimental voltage peaks.
The above disturbance can be abated by installing an RC filter
between the frequency converter and the motor.
Possible increased acoustic noise from the motor can be abated
by installing an LC filter which will also eliminate voltage peaks
from the frequency converter.
For further details, please contact your frequency converter
supplier or Grundfos.
Warning
Connect the pump to an external mains switch
placed close to the pump and to a motor-protective
circuit breaker.
It must be possible to lock the mains switch in OFF
position, isolated. Type and requirements as
specified in EN 60204-1, 5.3.2.
Warning
Before making any electrical connections, make sure
that the power supply has been switched off and that
it cannot be accidentally switched on.
The pump must be earthed.
TM
0
2
5
255
2
402
T
M
02
52
56
24
10
BM 4", BM/BMhp 6", BM/BMhp 8"
Direct-on-line
TM
00
4
035
16
94
RD
BM/BMB
YE
BK
0,47 µF
0.47
μ
F
RD = Red
YE = Yellow
BK = Black
BM/BMB
M
S
U
P
P
L
Y
L3
L2
L1
Yellow:W
Red :V
Black :U
Black
Red
Yellow
BK = Black
RD = Red
YE = Yellow
BM/BMhp 6", BM/BMhp 8"
Star-delta starting
TM
00
40
34
31
97
Caution
If a Grundfos MS motor with a temperature
transmitter is connected to a frequency converter, a
fuse incorporated in the transmitter will melt and the
transmitter will be inactive. The transmitter cannot be
reactivated. This means that the motor will operate
like a motor without a temperature transmitter.
W2
V2
U2
W1
V1
B2
R2
Y2
R1
Y1
R
O
F
Y
L
P
P
U
S
B=Black, R=Red, Y=Yellow
U1
M
B1
BK = Black
RD = Red
YE = Yellow