Grundfos MTR 1, Instructions Manual

Page: 12 / 86

6. Electrical connection
WARNING
Electric shock
Death or serious personal injury
‐
Switch off the power supply before you
start any work on the product.Make
sure that the power supply cannot be
switched on accidentally.
‐
Connect the product to an external
main switch close to the product and to
a motor-protective circuit breaker or a
CUE frequency converter. Make sure
that you can lock the main switch in
OFF position (isolated). Type and re-
quirements as specified in EN
60204-1, 5.3.2.
All electrical connections must be carried
out by a qualified electrician in accordance
with local regulations.
Check that the supply voltage and fre-
quency correspond to the values stated on
the nameplate.
Carry out the electrical connection as
shown in the wiring diagram located inside
the terminal box cover.
Single-phase Grundfos motors incorporate a thermal
switch and require no additional motor protection.
Three-phase motors must be connected to a motor-
protective circuit breaker.
6.1 Changing the terminal box position
WARNING
Electric shock
Death or serious personal injury
‐
Switch off the power supply before you
start any work on the product. Make
sure that the power supply cannot be
switched on accidentally.
The terminal box can be turned to four positions in
90° steps.
270
o
180
o
90
o
0
o
TM004257
Terminal box positions, top view
Follow this procedure to change the terminal box
position:
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. Refit and tighten the bolts.
5. Refit the coupling guards.
6.2 Frequency converter operation
You can use three-phase motors for frequency
converter operation following the conditions below.
This section applies to motors defined in IEC 60034.
Related information
10.7 Noise
6.2.1 General conditions
Protect all motors used with frequency converters
against voltage peaks and dU/dt according to IEC
60034-17. Grundfos recommends that you use
insulated bearings for motors from frame size 225 (45
kW/2-pole, 30 kW/4-pole and 22 kW/6-pole).
12
English (GB)