Electrical Connection - Three-Phase Pumps Up To; Electrical Connection - Three-Phase Pumps, 11-22 Kw - Grundfos TPE 2000 Series Installation And Operating Instructions Manual

5.3 Electrical connection - three-phase pumps up to

7.5 kW
Warning
The user or the installer is responsible for the
installation of correct earthing and protection
according to local standards. All operations must be
carried out by qualified staff.
Warning
Never make any connections in the pump terminal
box unless all electric supply circuits have been
switched off for at least 5 minutes.
Note for instance that the signal relay may be
connected to an external supply which is still
connected when the mains supply is disconnected.
The above warning is indicated on the motor
terminal box by this yellow label.
5.3.1 Preparation
Before connecting the E-pump to the mains, take the issues
illustrated in the figure below into consideration.
L1
ELCB
L2
L3
PE
Fig. 6 Mains-connected pump with mains switch, backup
fuses, additional protection and protective earthing
5.3.2 Protection against electric shock - indirect contact
Warning
The pump must be earthed in accordance with local
regulations.
As the leakage current of 4 - 7.5 kW motors is
greater than 3.5 mA, take extra precautions when
earthing these motors.
EN 50178 and BS 7671 specify the following precautions when
the leakage current is greater than 3.5 mA:
• The pump must be stationary and installed permanently.
• The pump must be permanently connected to the power
supply.
• The earth connection must be carried out as duplicate
conductors.
Protective earth conductors must always have a yellow/green
(PE) or yellow/green/blue (PEN) colour marking.
5.3.3 Backup fuses
For recommended fuse sizes, see section
5.3.4 Additional protection
If the pump is connected to an electric installation where an earth
leakage circuit breaker (ELCB) is used as additional protection,
the circuit breaker must be of a type marked with the following
symbols:
This circuit breaker is type B.
The total leakage current of all the electrical equipment in the
installation must be taken into account.
The leakage current of the motor in normal operation can be seen
in section 21.3 Leakage current.
During start and at asymmetrical supply systems, the leakage
current can be higher than normal and may cause the ELCB to
trip.
L1
L2
L3
20.1 Supply voltage.
ELCB
5.3.5 Motor protection
The pump requires no external motor protection. The motor
incorporates thermal protection against slow overloading and
blocking (IEC 34-11, TP 211).
5.3.6 Protection against mains voltage transients
The pump is protected against voltage transients by built-in
varistors between the phases and between phases and earth.
5.3.7 Supply voltage and mains
3 x 380-480 V - 10 %/+ 10 %, 50/60 Hz, PE.
The supply voltage and frequency are marked on the pump
nameplate. Make sure that the pump is suitable for the power
supply of the installation site.
The wires in the terminal box must be as short as possible.
Excepted from this is the protective earth conductor which must
be so long that it is the last one to be disconnected in case the
cable is inadvertently pulled out of the cable entry.
Fig. 7 Mains connection
Cable glands
Cable glands comply with EN 50626.
2 x M16 cable gland, cable diameter ∅4-∅10
•
1 x M20 cable gland, cable diameter ∅9-∅17
•
• 2 x M16 knock-out cable entries.
Warning
If the supply cable is damaged, it must be replaced
by qualified staff.
Grid types
Three-phase E-pumps can be connected to all grid types.
Warning
Do not connect three-phase E-pumps to a mains
supply with a voltage between phase and earth of
more than 440 V.
L1
L1
L2
L2
L3 L3
9