Grundfos CUE - Page 8

Electrical connection
WARNING
Electric shock
Death or serious personal injury
‐
Before starting any work on the
product, make sure that the power
supply has been switched off and
that it cannot be accidentally
switched on. See the section
regarding installation requirements.
‐
Touching the electrical parts may
be fatal, even after CUE has been
switched off.
The owner or installer is responsible
for ensuring correct earthing and
protection according to
local regulations.
For products with STO, ensure short-
circuit protection of the cable between
terminal 37 and the external safety
device.
Security measures are the
responsibility of the user.
The frequency converter parameters
can be password protected.
TM038525
ELCB
Example of three-phase mains connection of CUE with main
switch, backup fuses and additional protection
Protection against electric shock, indirect contact
CAUTION
Electric shock
Minor or moderate personal injury
‐
CUE must be earthed correctly and
protected against indirect contact
according to local regulations.
The leakage current to protective earth
exceeds 3.5 mA, and a reinforced
earth connection is required.
Protection against short circuit, fuses
CUE and the supply system must be protected against short circuit.
Grundfos requires that the backup fuses mentioned in section
"Cable cross-section to signal terminals" are used for protection
against short circuit.
CUE offers complete short-circuit protection in case of a short circuit
on the motor output.
Additional protection
WARNING
Electric shock
Death or serious personal injury
‐
The leakage current to protective
earth must exceed 3.5 mA.
If CUE is connected to an electrical installation where an earth
leakage circuit breaker (ELCB/RCD) is used as additional
protection, the circuit breaker must be of a type marked with the
following symbols:
TMA06789TM006789
ELCB/RCD
The 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 CUE in normal operation can be seen in the
electrical data section.
During startup and in asymmetrical supply systems, the leakage
current can be higher than normal and may cause the ELCB/RCD
to trip.
EMC-correct installation
The motor cable must be screened for
CUE to meet EMC requirements.
Mains and motor connection
Check that the mains voltage and
frequency correspond to the values on
the nameplate of CUE and the motor.
The motor cable must be screened for
CUE to meet EMC requirements.
Wiring diagram
The wires in the terminal box must be as short as possible.
Excepted from this is the protective conductor which must be so
long that it is the last one to be disconnected in case the wire is
inadvertently pulled out of the cable entry.
TM038799
Wiring diagram, three-phase mains connection
8
English (GB)