This quadruple pump station has been overhauled utilizing the existing motors and pumps.  All motors have been rewound for Inverter duty, bearings have been replaced and pumps overhauled completely.    All tolerances in the pumps were checked to factory specifications to insure the highest efficiency.  Impeller buildup work was done to eliminate chips and crevices. The motors were re-installed on the mounting bases.
 

Toshiba Variable Frequency Drives installed to:

1.      Reduce electricity usage.  These motors operate in the 40to 60Hz range.  As such there is approximately a 30-50% reduction in electrical usage.

2.      Control the volume of pumping

3.      Controlling the substation remotely.

4.      Cycle pumps for longevity

5.      Reduce maintenance:

A.     sensing overloads and automatically stopping

B.     Cycling so seals do not dry out

The controller is a BihlerTech AT2K.  This controller is unique in that it operates not on a speed curve as most other controllers do but rather on a torque curve.  This enable the control to maximize the point of the curve where the efficiency is at its highest point.  This is important because not all pumps are the same, therefore the control senses where, on that particular pump, the load operates best.

Operation of the lift station goes through this control.  The following functions can be individually set and or monitored per motor/drive.  Starting, stopping, adjusting torque settings, reset hour meters, Hz, Amps.  Also the level of the wet well is also known at all times.

In the application to the right, this well is set for starting at 40” level ± ¼”,  the second pump is set for 50”, third set for 60” and the fourth set for 70”.  Total depth of the well is about 14 feet.  All pumps shut down and sleep at 30” and below.