Grundfos SE - Troubleshooting

8.3 Power cable data
Cable type Outer cable diameter [mm] Minimum bending radius
[mm
2
]
min. max. [mm]
Standard power cable
4 × 10 20.9 23.4 70
4 × 16 23.8 26.3 80
4 × 25 28.9 31.4 100
Screened EMC power cable
4 × 10 23.1 25.1 100
4 × 16 26.6 29.6 120
3 × 25 + 3G16/3 25.3 28.3 120
3 × 35 + 3G16/3 28.3 31.3 130
Screened EMC sensor cable
10 × 1.5 16.7 18.7 80
18 × 1.5 24 27 110
8.4 Sensors
The pumps can be equipped with various switches and sensors for protection. The specification table below indicates which switch and sensor
types can be used.
Switch and sensor specification
Standard pump Sensor version 1 Sensor version 2
Thermal switches / PTC ● ● ●
Moisture switch ● ● ●
Float switch in leakage chamber ● ● ●
Pt100 in motor winding ● ●
Pt100 in upper bearing ● ●
Pt100 in lower bearing ● ●
PVS3 vibration sensor ● ●
SM113 (integrated in the motor top) ●
IO113 (not integrated in the motor top) ●
Voltage tolerances
Component
Voltage Tolerance
Motor See the pump nameplate ± 10 %
Thermal switches Maximum 24 V DC ± 10 %
Thermistors 2.5 - 7.5 V -
Moisture switches 12-24 V DC -
Other sensors (optional) Maximum 14 V DC ± 1 V
SM 113 (optional) Maximum 14 V DC ± 1 V
8.5 Thermal switches
Three bimetallic thermal switches are built into the stator windings. A contact opens in case of overtemperature (150 °C). The motor insulation
is class H (180 °C).
The supply voltage to the thermal switches must be 12-24 V DC.
The thermal switches are connected to the control cable and must be connected to the safety circuit of the separate pump controller.
Use a multimeter to check that the circuit resistance does not exceed the maximum of 1.5 Ω (including 3 x PTO and control cable) at 20°C.
The motor-protective circuit breaker of the pump controller must include a circuit which automatically disconnects the power supply in
case the protective circuit is opened.
8.6 Moisture switches and leakage switches
One moisture switch and one leakage switch are installed in the pump. The moisture switch is placed in the top cover and the leakage switch
is in the chamber above the shaft seal.
8.7
Thermistors
The standard pump range has bimetallic thermal switches connected, however, a pump with PTC thermistors connected are available as a
Factory Product Variant (FPV).
The thermistors can be used as motor protection devices to monitor stator temperature instead of thermal switches and must be connected to
the thermistor relay in the control cabinet.
The operating voltage of PTC thermistors is 2.5 - 7.5 V.
After the electrical connection, use a multimeter to:
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English (GB)