Safety system and method for pump and motor

Patent metadata

Field	Value
Publication number	US-9712098-B2
Application number	US-201314056625-A
Country	US
Kind code	B2
Filing date	Oct 17, 2013
Priority date	Jun 9, 2009
Publication date	Jul 18, 2017
Grant date	Jul 18, 2017

Abstract

Embodiments of the invention provide a variable frequency drive system and a method of controlling a pump driven by a motor with the pump in fluid communication with a fluid system. The drive system and method can provide one or more of the following: a sleep mode, pipe break detection, a line fill mode, an automatic start mode, dry run protection, an electromagnetic interference filter compatible with a ground fault circuit interrupter, two-wire and three-wire and three-phase motor compatibility, a simple start-up process, automatic password protection, a pump out mode, digital input/output terminals, and removable input and output power terminal blocks.

First claim

The invention claimed is:

1. A method of controlling, a pump driven by a motor, the pump and the motor installed in a well, the motor connected to a variable frequency drive, the method comprising:
connecting the variable frequency drive to a previously-installed motor in order to retrofit the motor;
selecting, via a control pad, a motor connection type for the previously-installed motor wherein the selecting of the motor connection type includes selecting a motor connection type from a plurality of different motor connection types including a two-wire, single phase motor or a three-wire, single phase motor;
automatically setting a minimum frequency and a maximum frequency output from the variable frequency drive to the motor based on the motor connection type selected via the control pad; and
generating with the drive a first waveform and a second waveform, the second waveform having a phase angle of about 90 degrees offset from the first waveform in order to control the three-wire, single-phase motor, where the motor is indicated to be the three-wire, single phase motor.

2. The method of claim 1 wherein the two-wire, single phase motor is a permanent split capacitor motor.

3. The method of claim 1 , further including:
entering a service factor current value using the control pad;
entering a current time using the control pad;
entering a current date using the control pad; and
engaging one of a pump-out button and an automatic start button on the control pad.

4. The method of claim 1 , further comprising:
reducing electrical noise generated by the motor by adding an electromagnetic interference (EMI) filter to the drive such that the drive is simultaneously compatible with a Ground Fault Circuit Interrupter (GFCI).

5. The method of claim 1 , further comprising:
engaging a pump-out button of the control pad to enable the drive to enter a pump-out mode for discharging sand and dirt from the well.

6. The method of claim 1 , further comprising:
maintaining a constant water pressure by increasing or decreasing a speed of the motor, wherein the speed to be increased or decreased is determined by a controller of the variable frequency drive.

Assignees

• Pentair Flow Tech Llc
• Danfoss Drives As

Inventors

• Kidd Melissa Drechsel
• Genaw William James
• Pasche Micheal Robert
• Baase Ii Gary Thomas
• Berthelsen Lars Hoffmann
• Fink Rasmus
• Holm Martin Skov

Classifications

• H02H1/04

  Arrangements for preventing response to transient abnormal conditions, e.g. to lightning {or to short duration over voltage or oscillations; Damping the influence of DC component by short circuits in AC networks} · CPC title

• H02H7/0822

  Integrated protection, motor control centres · CPC title

• F04D15/0066 Primary

  by changing the speed, e.g. of the driving engine · CPC title

• H02P25/04 Primary

  Single phase motors, e.g. capacitor motors · CPC title