Three-Phase Pumps, 20-30 Hp; Protection Against Electric Shock - Indirect Contact; Backup Fuses - Grundfos CRE Instrucciones De Instalación Y Funcionamiento

3.4 Three-phase pumps, 20-30 hp

DANGER
Electric shock
Death or serious personal injury
– The user or the installer is responsible for the
installation of correct grounding and protection
according to current national and local
standards. All operations must be carried out by
qualified personnel.
DANGER
Electric shock
Death or serious personal injury
– 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 power supply is
disconnected.
WARNING
Hot surface
Death or serious personal injury
– The surface of the terminal box may be above
158 °F (70 °C) when the pump is operating.
3.4.1 Preparation
Before connecting the E-pump to the power supply, take the
issues illustrated in the figure below into consideration.
L1
L2
ELCB
L3
PE
Fig. 2 Power supply-connected pump with power switch,
backup fuses, additional protection and protective
grounding

3.4.2 Protection against electric shock - indirect contact

DANGER
Electric Shock
Death or serious personal injury
– The pump must be grounded in accordance
– As the leakage current of 20-30 hp motors is
EN 61800-5-1 specifies that the pump must be stationary and
installed permanently when the leakage current is > 10 mA.
One of the following requirements must be fulfilled:
• A single protective ground lead (7 AWG minimum copper)
Fig. 3 Connection of a single protective ground lead using
one of the leads of a 4-core power cable (7 AWG
minimum)
• Two protective ground leads of the same cross-sectional area
L1
as the power supply leads, with one lead connected to an
L2
additional ground terminal in the terminal box.
L3
Fig. 4 Connection of two protective ground leads using two of
the leads of a 5-core power supply cable
Protective ground leads must always have a yellow/green (PE) or
yellow/green/blue (PEN) color marking.

3.4.3 Backup fuses

For recommended fuse sizes, see section
with national regulations.
> 10 mA, take extra precautions when
grounding these motors.
8.1.1 Supply voltage.
7