Electrical Connection - Three-Phase Pumps, 0.75-7.5 Kw; Mains Switch; Protection Against Electric Shock - Indirect Contact; Additional Protection - Grundfos CRE Installation And Operating Instructions Manual

NC C NO N PE L
0-10 V
0/4-20 mA
4-20 mA
0/1
1 9 8 7
STOP
RUN
0/4-20 mA 0-10 V
10K
6 5 4 3 2
Fig. 5 Connection terminals
3.5 Electrical connection – three-phase pumps,
0.75-7.5 kW
The user or the installer is responsible for the
installation of the correct earthing and protection
according to valid national and local standards.
Caution
All operations must be carried out by a qualified
electrician.
Warning!
All electric supply circuits must be interrupted
before working in the pump terminal box.
Never make any connections in the pump
terminal box unless the electricity supply has
been switched off for at least 5 minutes.

3.5.1 Mains switch

The pump must be connected to an external all-pole mains switch
with a contact separation of at least 3 mm in each pole according
to IEC 364.
6
1: Digital input
9: GND (frame)
8: +24 V
7: Sensor input
B: RS-485B
Y: Screen
B Y A
A: RS-485A
6: GND (frame)
5: +10 V
4: Setpoint input
3: GND (frame)
2: Start/stop
3.5.2 Protection against electric shock – indirect contact
The pump must be earthed and protected against
indirect contact in accordance with national
regulations.
Protective earth conductors must always have a yellow/green
(PE) or yellow/green/blue (PEN) colour marking.
As the leakage current of 4 kW to 7.5 kW motors
is > 3.5 mA, these motors must be connected to
Caution
especially reliable/sturdy earth connections.
The leakage current of the motor can be found in section
13.2 Leakage current.
EN 50 178 and BS 7671 specify the following:
Leakage current > 3.5 mA:
The pump must be stationary and installed permanently.
Furthermore, the pump must be connected permanently to the
electricity supply.
• The earth connection must be carried out as duplicate
conductors.

3.5.3 Additional protection

If the pump is connected to an electric installation where an earth
leakage circuit breaker is used as additional protection, this
circuit breaker must be of the type:
• which is suitable for handling leakage currents and cutting-in
with short pulse-shaped leakage.
• which trips out when alternating fault currents and fault
currents with DC content, i.e. pulsating DC and smooth DC
fault currents, occur.
For these pumps an earth leakage circuit breaker type B must be
used.
This circuit breaker must be marked with the following symbols:
When an earth leakage circuit breaker is
selected, the total leakage current of all the
Note
electrical equipment in the installation must be
taken into account.
The leakage current of the motor can be found in section
13.2 Leakage current

3.5.4 Motor protection

The pump requires no external motor protection. The motor
incorporates thermal protection against slow overloading and
blocking (IEC 34-11: TP 211).
ELCB