Safety system and method for pump and motor

• US 9,712,098 B2
• Filed: 10/17/2013
• Issued: 07/18/2017
• Est. Priority Date: 06/09/2009
• Status: Active Grant

• Current Assignee: Danfoss Drives A/S (Danfoss A/S), Pentair Flow Technologies LLC (Pentair Plc (Ireland))
• Original Assignee: Danfoss Drives A/S (Danfoss A/S), Pentair Flow Technologies LLC (Pentair Plc (Ireland))
• Inventors: Kidd, Melissa Drechsel, Genaw, William James, Pasche, Micheal Robert, Baase, II, Gary Thomas, Fink, Rasmus, Holm, Martin Skov, Berthelsen, Lars Hoffmann
• Primary Examiner(s): Duda, Rina
• Application Number:
  US14/056,625
• Publication Number:
  US 20140042955A1
• Time in Patent Office: 1,370 Days
• Field of Search: 318727, 318751, 318752, 318772, 318774
• CPC Class Codes: F04D 15/0066 by changing the speed, e.g. of the driving engine
• CPC Class Codes: H02H 1/04 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 Class Codes: H02H 7/0822 Integrated protection, motor control centres
• CPC Class Codes: H02P 25/04 Single phase motors, e.g. capacitor motors

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.

Claims

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.