MP 1, SQE-NE, SPA-NE, SP-NE - SCL Water

Submersible pumpsSubmersible pumpsSP EnvironmentalOvertemperature protectionAccessories for protection against overtemperature isavailable for the MS 4000 RE submersible motors.When the temperature becomes too high, theprotection device will cut out the motor, thus preventingdamage to pump and motor.The motor can be restarted in two ways after a cut-out:• manual restarting• automatic restarting.The Grundfos MS submersible motors except MS 402are available with a built-in Tempcon temperaturetransmitter for protection against overtemperature. Bymeans of the transmitter it is possible to read out and/or monitor the motor temperature via an MP 204 or aPR 5714 relay.The Grundfos MS6 submersible motors can be fittedwith a Pt100. The Pt100 is fitted in the motor andconnected directly to the MP 204 or monitored by thePR 5714 relay.Protection against upthrustIn case of a very small counter-pressure in connectionwith start-up, there is a risk that the entire pump bodymay rise. This is called upthrust and it may damageboth pump and motor. Therefore, both Grundfos pumpsand motors are protected against upthrust as standard,preventing upthrust from occurring in the critical startupphase. The protection consists of either a built-instop ring or a hydraulic balancing device.Built-in cooling chambersIn all Grundfos MS submersible motors, type RE,efficient cooling is ensured by means of coolingchambers fitted at the top and at the bottom of themotor, and by internal circulation of motor liquid, seedrawing to the right. As long as the required flowvelocity past the motor is maintained (see "Operatingconditions" page 46) cooling of the motor will beefficient.TM00 5698 0996Fig. 35 MS 4000 RE, internal circulation48