Grundfos SPE 8 in Submersible Well Pump

Grundfos SPE is a speed-controlled submersible pump system: the SP stainless steel pump end on a Grundfos MS6000P interior permanent magnet (IPM) motor, run through a variable frequency drive such as the Grundfos CUE. The drive matches pump speed to demand, so the pump holds a constant pressure, flow or level as the duty changes, and Grundfos rates the system for a low running cost in changing operating conditions.

The MS6000P is a 4-pole synchronous motor with the magnets embedded in a hermetically sealed rotor, a canned stator, silicon carbide shaft seal faces and heavy duty thrust bearings. Grundfos quotes 8-10% higher efficiency than an asynchronous motor of the same output, in a lighter, more compact motor. The motor runs at 3 × 410 V and up to 3600 rpm (120 Hz) from the drive.

Typical uses listed by Grundfos include water supply, irrigation, groundwater lowering, pressure boosting, fountains, mining and offshore applications. The CUE soft-starts the motor, protects the installation against water hammer and runs the predefined constant pressure, constant flow and constant level modes.

The one thing to plan for: an SPE motor cannot be connected straight to the power line. It needs a variable frequency drive with IPM motor control and an IPM-ready sine-wave filter, both sold separately; the matching Grundfos CUE drive and filter part numbers are in the Models & Ratings table.

24 months from date of installation, but not more than 30 months from date of manufacture. In Grundfos's words, products are “warranted to the original user only to be free of defects in material and workmanship”; the full terms are in the installation and operating instructions on the Data Sheet tab.

Grundfos extends this to a 5-year system warranty when the SPE complete pump is purchased together with a Grundfos CUE drive (Grundfos US price list, January 2026).

Each SPE serves one well, with its own CUE drive. The CUE supports duty and standby operation across two pumps; for a set, or a flow outside what one pump carries, send us the duty and we will size the pumps and drives with you.

The model code reads flow class, motor horsepower and stages: SPE385S400-4 is the SPE 385S (385 GPM class) on a 40 HP motor with 4 stages. The MS6000P comes in 10, 25, 40 and 50 HP executions; the pump power column shows the load each build places on it, which sets the CUE drive and filter size. In the selector, choose horsepower and motor size first, then voltage and phase, then the model, shown with its nominal head at rated flow and full speed. The part number for every build is in the Models & Ratings table.