English (GB)
9
7.4 Additional protection
The residual-current circuit breaker must be marked
with the following symbol:
The total leakage current of all the electrical
equipment in the installation must be taken into
account. You find the leakage current of the motor in
sections 26.2 Leakage current and 27.2 Leakage
current (AC).
This product can cause a direct current in the
protective earth conductor.
Overvoltage and undervoltage protection
Overvoltage and undervoltage may occur in case of
unstable power supply or a faulty installation. The
motor is stopped if the voltage falls outside the
permissible voltage range. The motor restarts
automatically when the voltage is again within the
permissible voltage range. Therefore, no additional
protection relay is required.
Overload protection
If the upper load limit is exceeded, the motor
automatically compensates for this by reducing the
speed and stops if the overload condition persists.
The motor remains stopped for a set period. After
this period, the motor automatically attempts to
restart. The overload protection prevents damage to
the motor. Consequently, no additional motor
protection is required.
Overtemperature protection
The electronic unit has a built-in temperature sensor
as an additional protection. When the temperature
rises above a certain level, the motor automatically
compensates for this by reducing the speed and
stops if the temperature keeps rising. The motor
remains stopped for a set period. After this period,
the motor automatically attempts to restart.
Protection against phase unbalance
Three-phase motors must be connected to a power
supply with a quality corresponding to IEC
60146-1-1, class C, to ensure correct motor
operation at phase unbalance. This also ensures
long life of the components.
7.5 Connection terminals
The descriptions and terminal overviews in this
section apply to both single- and three-phase
motors.
For maximum torques, see section Torques, page
71.
7.5.1 Connection terminals, CRE, CRIE, CRNE,
SPKE and MTRE pumps
CRE, CRIE, CRNE, SPKE and MTRE pumps have a
number of inputs and outputs enabling the pumps to
be used in advanced applications where many inputs
and outputs are required.
The pumps have these connections:
• three analog inputs
• one analog output
• two dedicated digital inputs
• two configurable digital inputs or open-collector
outputs
• Grundfos Digital Sensor input and output
• two Pt100/1000 inputs
• two LiqTec sensor inputs
• two signal relay outputs
• GENIbus connection.
See fig. 8.
DANGER
Electric shock
- Death or serious personal injury
- Only use residual-current circuit
breakers (ELCB, GFCI, RCD) of type B.
The motor is protected against transients
from the power supply according to EN
61800-3. In areas with high lightning
intensity, we recommend external lightning
protection.