SQFlex data booklet

2. Features and benefits
Dry-running protection
The SQF pump is protected against dry running to prevent
damage to the pump. The dry-running protection is activated
by a water level electrode placed on the motor cable 0.3 to
0.6 m (12 to 24 in) above the pump, depending on the pump
type.
The water level electrode measures the contact resistance
to the motor sleeve through the water. When the water level
falls below the water level electrode, the pump stops. The
pump automatically restarts five minutes after the water
level is above the water level electrode.
0.3 to 0.6 m (12 to 24 in)
TM022436
Vertical installation
0.3 to 0.6 m (12 to 24 in)
TM078602
Horizontal installation
High efficiency
The MSF 3 motor is a permanent-magnet motor (PM motor)
featuring a higher efficiency within the power range
compared to a conventional asynchronous motor.
In addition, the segmented motor stator also contributes to
high efficiency.
The MSF 3 motor is characterized by a high locked-rotor
torque even at low power supply.
Over- and undervoltage protection
Over- and undervoltage may occur in case of unstable
power supply or a defective installation.
The pump stops if the voltage falls outside the permissible
voltage range. The motor automatically restarts when the
voltage returns within the permissible voltage range. No
extra protection relay is needed.
Note: The MSF 3 motor is protected against transients from
the power supply according to EN/IEC 61000-4-5 (6 kV). In
areas with high lightning intensity, we use external lightning
protection.
Overload protection
In case the upper load limit is exceeded, the motor
automatically compensates by reducing the speed. If the
speed falls below the minimum speed, the motor stops
automatically.
The motor remains stopped for 30 seconds, then the pump
automatically restarts.
The overload protection prevents the burnout of the motor.
No extra motor protection is required.
Overtemperature protection
A permanent-magnet motor gives off a small/negligible
amount of heat to its surroundings. In combination with an
efficient internal circulation system leading the heat away
from the rotor, stator and bearings, optimal operating
conditions are ensured for the motor.
As an extra protection, the electronic unit has a built-in
temperature sensor. When the temperature rises above 85
°C (185 °F), the motor automatically stops. Once the
temperature drops to 75 °C (165 ° F), the motor
automatically restarts.
Maximum Power Point Tracking
The built-in electronic unit gives the SQFlex system a
number of advantages compared to conventional products.
One of these advantages is the built-in microprocessor
with Maximum Power Point Tracking (MPPT).
Due to the MPPT function, the pump duty point is
continuously optimized according to the available input
power. MPPT is only available for pumps connected to DC
supply.
Wide voltage range
The wide voltage range enables the motor to operate at any
voltage from 30-300 VDC (100-300 VDC for 2500 W) or
90-240 VAC. This ensures easy installation and sizing.
SQFlex
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Features and benefits