Method and system for detection of faults in pump assembly via handheld communication device

Abstract

A method for detecting faults or operational parameters in a pump assembly by use of a handheld communication device is described. The pump assembly includes an electric motor and a pump, wherein the pump assembly or electric motor has at least one rotating shaft The method comprises the steps of: a) measuring a sound signal emanating from the pump assembly by use of a microphone connected to or implemented in the handheld communication device, b) processing the measured sound signal, and c) recognising one or more sound emanating condition including any possible faults by way of the processed sound signal. The app automatically repeats at least steps b) and c) for a plurality of preselected frequency ranges in order to detect different fault states.

1 . A method for detecting faults in a pump assembly including an electric motor and a pump by use of a handheld communication device running an app, the method comprising:
 a) measuring a sound signal emanating from the pump assembly by use of a microphone connected to or implemented in the handheld communication device,   b) processing the measured sound signal, and   c) recognizing one emanating condition including a possible fault state by way of the processed sound signal, wherein the app automatically repeats at least steps b) and c) for a plurality of preselected frequency ranges in order to detect different fault states.   
     
     
         2 . A method according to  claim 1 , wherein the method is carried out by carrying out a first measurement for a first duration of time for detecting a first fault state, and then carrying out a second measurement for a second duration of time for detecting a second fault state. 
     
     
         3 . A method according to  claim 2 , wherein the first measurement and the second measurement are carried out at two different positions relative to the pump assembly. 
     
     
         4 . A method according to  claim 1 , wherein the method is carried out by sequentially executing scans for individual fault states. 
     
     
         5 . A method according to  claim 4 , wherein the method is carried out by carrying out a first scan in a first frequency range for detecting a first fault state and then carrying out a second scan in a second frequency range for detecting a second fault state. 
     
     
         6 . A method according to  claim 5 , wherein the first frequency range is located in a first band near or in the kHz-range, advantageously up to 1 kHz, and the second frequency range is located in a second band in the kHz-range, advantageously 10-20 kHz. 
     
     
         7 . A method according to  claim 1 , wherein steps b) and/or c) are carried out via a processing unit, such as a DSP, implemented in the handheld communication device and/or a software app installed on the handheld communication device. 
     
     
         8 . A method according to  claim 1 , wherein fault states are identified among the group of: bearing faults, cavitation, dry running, water hammering and unbalance. 
     
     
         9 . A method according to  claim 8 , wherein the method at least carries out sequential detection of water hammering and cavitation. 
     
     
         10 . A method according to  claim 1 , wherein the processing step of step b) comprises the sub-steps of processing the measured sound signal so as to estimate the rotational speed of the rotating shaft and optionally normalizing the measured sound signals or processed sound signals and/or wherein the processing step of step b) optionally comprises the step of filtering out periodic signals of the processed signal, and wherein the recognition of step c) is carried out by use of the periodic signals. 
     
     
         11 . A method according to  claim 1 , wherein the handheld communication device provides a feedback, e.g. an audial, visual or vibrational feedback, when an acceptable measurement position of the microphone has been found. 
     
     
         12 . A fault detection system for detecting faults in a pump assembly, the fault detection system comprising:
 a pump;   an electric motor;   a handheld communication device, which includes a microphone for measuring sound emanating from the pump assembly or electric motor;   a processing unit implemented in the handheld communication device;   a software app installed on the handheld communication device for processing a measured sound signal measured via said microphone;   a recognition module for recognizing a fault condition by way of the processed sound signal, wherein the fault detection system is configured to automatically repeat a sequence of fault detection steps by processing the measured sound signal and recognizing one emanating condition including a possible fault state in a plurality of preselected frequency ranges in order to detect different fault states.   
     
     
         13 . A fault detection system according to  claim 12 , wherein the recognition module is implemented on the handheld communication device. 
     
     
         14 . A fault detection system according to  claim 12 , wherein the processing unit and/or filter module comprises an analysis module chosen from the group of:
 an RMS level detection module;   a spectral analysis module;   an envelope analysis module; or   a Cepstral analysis module.   
     
     
         15 . A non-transitory computer readable storage medium storing one or more programs, which when executed by a handheld communication device cause the handheld communication device to perform a method for a pump assembly including an electric motor and a pump by use of the handheld, the method comprising:
 a) measuring a sound signal emanating from the pump assembly by use of a microphone connected to or implemented in the handheld communication device,   b) processing the measured sound signal, and   c) recognizing one emanating condition including a possible fault state by way of the processed sound signal, wherein steps a)-c) are repeated for a plurality of different frequency ranges in order to detect different fault states.