7
During frequency converter operation, it is not advisable to run
the motor at a frequency higher than the rated frequency
(50 or 60 Hz). See motor nameplate.
9.1.1 Motor protection
The motor must be connected to an effective motor starter (MV)
and an external amplifier relay (FR). See fig. 7. This protects the
motor against damage from voltage drop, phase failure, quick
and slow overloading and a locked rotor.
In electricity supply systems where undervoltage and variations in
phase symmetry may occur, a phase failure relay should be
connected. See section
, point 1.
9.1.2 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 current of the motor.
To ensure optimum protection of the motor, the starter overload
unit should be set in accordance with the following guidelines:
1. Set the starter overload to the rated current (I
1/1
) of the motor.
2. Start the BM hp circulation pump and let it run for half an hour
at normal performance.
3. Slowly grade down the scale indicator until the motor trip point
is reached.
4. Increase the overload setting by 5 %, but not higher than the
rated current (I
1/1
) of the motor.
For motors wound for star-delta starting, the starter overload unit
should be set as above, but the maximum setting should be as
follows:
Starter overload setting = rated current (I
1/1
) x 0.58.
9.1.3 Generator operation
Motor-driven generators for standard motors are often available
according to standard conditions:
•
maximum height above sea level: 150 metres
•
maximum air intake temperature: 30 °C
•
maximum air humidity: 60 %.
Please contact Grundfos for advice.
9.1.4 Thermistor
If thermistors are used as protection, they must be connected to
terminals T1 and T2 before start-up. See fig. 7.
9.2 BM hp circulation pump
The electrical connection must be carried out by an authorised
electrician in accordance with local regulations.
The required voltage quality measured at the motor terminals is
– 10 %/+ 6 % of the rated voltage during continuous operation
(including variation in the supply voltage and losses in cables).
It must be checked that there is voltage symmetry in the
electricity supply lines, i.e. approximately same difference of
voltage between the individual phases. See also section
, point 1.
In order for the pump to meet the EC EMC Directive (2004/108/
EC), a 0.47 µF capacitor (in accordance with IEC 384-14) must
always be connected over the two phases to which the
temperature transmitter is connected. See fig. 8.
Fig. 8
Electrical connection, BM hp circulation pump
The electrical connections must be made in the terminal box.
See figs 8, 9, 10 and 11.
Fig. 9
Position of terminal box, BM hp circulation pump
Fig. 10
BM hp circulation pump, direct-on-line starting
Fig. 11
BM hp circulation pump, star-delta starting
Note
If this requirement is not met, the motor warranty
will be invalidated.
Warning
Before making any electrical connections, make
sure that the electricity supply has been switched
off and that it cannot be accidentally switched
on.
The pump must be connected to an external
mains switch with a minimum contact gap of
3 mm in all poles.
The pump must be earthed.
TM
02
94
58
26
04
T
M
02
52
56
24
02
TM
0
0
4
035
1
694
T
M
00
40
34
31
97
RD
YE
BK
0,47 µF
RD = red
YE = yellow
BK = black
BM hp
0.47 µF
BM/BMB
Terminal box
BM hp
M
S
U
P
P
L
Y
L3
L2
L1
Yellow:W
Red :V
Black :U
Yellow
Black
Red
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
B = black
R = red
Y = yellow
