Electrical Connection; General - Grundfos MS Montage- Und Betriebsanleitung

5. Electrical connection

Warning
Before starting work on the product,
switch off the power supply. Make sure
that the power supply cannot be
accidentally switched on.

5.1 General

The electrical connection must be carried out by an
authorised electrician in accordance with local
regulations.
The supply voltage, rated maximum current and
cos φ appear from the separate nameplate that must
be fitted close to the installation site.
The required voltage quality for Grundfos MS and
MMS submersible motors, measured at the motor
terminals, is - 10 %/+ 6 % of the nominal voltage
during continuous operation (including variation in
the mains voltage and losses in cables).
Furthermore, check that there is voltage symmetry in
the power supply lines, i.e. same difference of
voltage between the individual phases. See also
section 10. Checking of motor and
Warning
The motor must be earthed.
The motor must be connected to an
external mains switch with a minimum
contact gap of 3 mm in all poles.
If MS motors with a built-in temperature transmitter
(Tempcon) are not installed together with an MP 204
motor protection unit, they must be connected to a
0.47 μF capacitor approved for phase-phase
operation (IEC 384-14) to meet the EC EMC
directive (2004/108/EC). The capacitor must be
connected to the two phases to which the
temperature transmitter is connected. See fig. 6.
10
cable, item 2.
The motors are wound for direct-on-line starting or
star-delta starting, and the starting current is
between four and six times the rated current of the
motor.
The run-up time of the motor is only about
0.1 second. Direct-on-line starting is therefore
normally approved by the power supply company.
0.47 μF
1 = L1: Brown
2 = L2: Black
3 = L3: Grey
4 = PE: Yellow/green
Fig. 6 Connection of capacitor