Grundfos SP Submersible Motors
Features and benefits
A complete motor range
Grundfos offers a complete range of submersible motors in different voltages:
Submersible motors, MS
• 4" motors, single-phase from 0.37 to 2.2 kW:
- 2-wire
- 3-wire
- PSC (permanent split capacitor)
• 4" motors, three-phase from 0.37 to 7.5 kW
• 4" T60 motors, three-phase from 2.2 to 5.5 kW
• 6" motors, three-phase from 5.5 to 30 kW
• 6" T60 motors, three-phase from 5.5 to 22 kW.
Submersible, rewindable motors, MMS
• 6" motors, three-phase from 3.7 to 45 kW
• 8" motors, three-phase from 22 to 110 kW
• 10" motors, three-phase from 75 to 190 kW
• 12" motors, three-phase from 147 to 250 kW.
High motor efficiency
Within the area of high motor efficiency, Grundfos is a market leader.
Rewindable motors
The 2-pole Grundfos MMS submersible motors are all easy to rewind. The windings of the stator are made of a special waterproof wire of pure electrolytic copper sheathed with special non-hydroscopic thermoplastic material. The fine dielectric properties of this material allow direct contact between the windings and the liquid for efficient cooling of the windings.
Industrial motors (T60)
For heavy-duty applications, Grundfos offers a complete motor range of T60 motors with up to 5 % higher efficiency than that of Grundfos' standard motors. The T60 motors are available in sizes 2.2 to 22 kW. The cooling of the motor is very efficient due to the large motor surface.
The efficient cooling makes it possible to increase the liquid temperature to 60 °C at a minimum flow of 1 m/s past the motor. The T60 motors are for customers who value low operating costs and long life higher than price.
Grundfos T60 motors are developed for difficult operating conditions. These motors will stand a higher thermal load than standard motors and thus have a longer life when subjected to high load. This applies whether the high load is caused by, for example, bad power supply, hot water, bad cooling conditions, high pump load.
Please note that heavy-duty motors are longer than motors for standard conditions.
Overtemperature protection
Protecting the motor against too high motor temperature is the simplest and cheapest way of avoiding that the motor life is reduced.
Accessories for protection against overtemperature are available for both Grundfos MS and MMS submersible motors. When the temperature becomes too high, the protection device cut outs, and thereby avoids damage to the pump and motor.
MS
The Grundfos MS submersible motors, except MS 402, are available with a built-in Tempcon temperature sensor for protection against overtemperature. By means of this sensor connected to the MP 204 motor protector via the power line, you can read out and/or monitor the motor
temperature. As an alternative, you can fit the MS motors with Pt100 and Pt1000 sensors for temperature monitoring via a control unit.
MMS
The Grundfos MMS submersible motors are not available with built-in Tempcon temperature sensor. For these motors, we offer Pt100 and Pt1000 sensors for temperature monitoring. Together with a control unit, the sensor ensures that the maximum operating temperature
is not exceeded.
Protection against upthrust
In case of a very low counter pressure in connection with startup, there is a risk that the entire chamber stack may rise. This is called upthrust. Upthrust may damage both pump and motor. Therefore, both Grundfos pumps and motors are protected against upthrust as standard, preventing upthrust from occurring in the critical startup phase. The protection consists of either a built-in stop ring or hydraulic balancing.
Built-in cooling chambers
In all Grundfos MS submersible motors, cooling chambers at the top and at the bottom of the motor and internal circulation of motor liquid ensure efficient cooling. As long as the required flow velocity past the motor is maintained (see section > on page), cooling
of the motor will be efficient.
Lightning protection
Grundfos recommends that you use extra lightning protection to minimise the risk of motor burnout caused by lightning strike.
Reduced risk of short-circuit
The stator is hermetically encapsulated in stainless steel. The stator windings are embedded in polymer compound. This results in high mechanical stability, optimum cooling and eliminates the risk of short circuits in the windings caused by condensing water.
Shaft seal
MS 402
The shaft seal is of the lip seal type characterised by low friction against the rotor shaft.
The choice of rubber offers good wear resistance, good elasticity and resistance to particles. The rubber material is approved for use in potable water.
MS 4000, MS 6000
The material is ceramic/carbon carbide providing optimum sealing, optimum wear resistance and long life.
The spring-loaded shaft seal is designed with a large surface and a sand shield. The result is a minimum exchange of pumped liquid and motor liquid and no penetration of particles.
Motors, version R, have a SiC/SiC shaft seal according to DIN 24960. Other combinations are available on request. MMS rewindable motors
The standard shaft seal is a ceramic/carbon mechanical shaft seal. The shaft seal is replaceable. The material provides good wear resistance and resistance to particles. Together with the shaft seal housing, the sand shield forms a labyrinth seal, which during normal operating conditions prevents penetration of sand particles into the
shaft seal.
On request, motors can be supplied with a SiC/SiC seal according to DIN 24960.
