Wireless sensors in asset monitoring: resistance and misgivings

The saying “the only constant is change,” while cliché, has never made more sense than in this day and age.   

The digital world is full of variables and changes happen relatively frequently, with technology driving many of them.   

Although change is increasingly a constant and part of our daily lives, people still tend to be resistant. And this is understandable. It can be difficult to adjust to something new, to a new routine, to new technology. 

From a new team member joining the group, another one leaving, or maybe the company itself going through some kind of organizational change, to adopting new technologies and processes. All of this has a degree of complexity and difficulty for the people involved. 

On a more personal note, at Dynamox, a technology company focused on asset monitoring, we feel this resistance on a daily basis. A few years ago, we introduced wireless vibration and temperature sensors in the market. We can say, without false modesty, that we were pioneers in this type of technology, along with a few other players in the world market. 

Naturally, misgivings were present, some of which remain to this day. Many analysts, accustomed to the traditional method of collecting vibration data with portable handheld collectors on biweekly, monthly, or even more widely spaced offline routes, looked with disbelief at a new, completely wireless technology and cloud-based analysis platform. And indeed, it is something truly disruptive, which over time has changed the routine of many years of more experienced analysts. 

We know that many leaders encounter resistance when implementing new technologies in their teams, and that many technicians encounter colleagues who may also be resistant to new ways of working. Below, we will list some of the main sources of resistance we have heard over the years and our humble opinion on each of them, in the hope that this text can help you overcome some of these barriers. 

“With these wireless sensors, will I see the same vibration data I see with the traditional system?”  

They are different technologies, with the same principle, but with different electronic and mechatronic components. The very form of installation often changes in relation to traditional systems (magnet vs. glue vs. screw). The number and positioning of the wireless sensors can also change if we think in a uniaxial (traditional) versus triaxial (wireless sensor) comparison. 

But of course, these variations should not be so large as to hinder the analysis (considering quality wireless sensors). The identification of the excited frequency data in the machine must be the same or very similar, because this is about the mechanics of the asset. 

At Dynamox, in order to ensure the accuracy of the data collected, we make various comparisons of our system with traditional systems / calibrated reference accelerometers.  

In summary, yes, with the care of using the same maximum frequency, the same filters and parameters, the data collected by quality wireless sensors should be very similar or even identical to traditional systems, as can be seen in the following example on data collected on a pump, for the velocity spectrum and waveform autocorrelation plots. 

“So, with wireless sensors, will I be able to detect the same faults that I detect with my traditional system?” 

We believe that an assertive analysis is a combination of factors: 1) a good data collection system; 2) good analysis and detection tools in the monitoring system; 3) good settings to optimize the use of the system and 4) a good vibration analyst.   

Assuming the first three items are met, and we believe the Dynamox system delivers this required quality, a qualified analyst will still be important for the analysis (or double-check) and recommended action. And here comes back the issue of resistance that we commented on earlier. Many times, the analyst has worked with the same analysis system all his life and is used to operating in that routine. It is natural that the change to another system is seen with some caution, but then the question remains: Is the analyst in charge of analyzing just the platform, or does he/she actually have the background and technical knowledge for the analysis?

Over the years, we have seen that even the most demanding analysts can adapt to a new system, if it is of such quality and brings benefits that justify the change from an X system to a Y system. As a conclusion, yes, with a good wireless monitoring system and skilled people to operate it, one should be able to identify the same flaws found via a traditional system. And the best, all this with collection systems that are much more frequent and take inspectors out of the field, scoring positively on safety and labor optimization. 

“I have no confidence in cloud data, I prefer to have my data stored locally.” 

This resistance is perhaps one of the strongest. We usually hear more from IT teams, though it is not restricted, and is usually a shared view with other areas. 

At Dynamox, we believe that what guarantees security are processes and qualified people, not the fact of working on a local server. Also, what is the probability of a local server surviving the same number of cyberattacks as an online server of one of the four major players in the market (Google, Amazon, Azure, and Oracle) if the ratio is 1 to 10.000? 

Another point is that working in the cloud has several advantages. To name a few: 

• There is no need to maintain physical infrastructure, subjected to natural disasters and on-site maintenance. 
• Availability and easy access: in terms of access, because it is in the cloud, the analysis software can be accessed from anywhere and in a matter of seconds, and not just within the company, as is the case with local servers. 
• Data security: Much has evolved in encryption and access controls in recent years. In this respect, Dynamox has several data security certifications to ensure that the best practices are followed: ISO 27001, ISO 27701, and ISO 27018. 
• Alarm management: a cloud system favors online management by emailing critical cases, for example, enabling immediate actions to prevent breakdowns and corrective actions.  
• Data integration: Cloud data also facilitates software integrations and data centralization. 

“This automation of data collection using wireless sensors will make me, as an inspector, lose my job.” 

This is sometimes a fear of the people involved in the process of collecting data from the machines in the field. However, we have seen with our customers that there is a huge demand for labor in the market, especially for skilled labor. What we see, because of this, is a reallocation of labor, specialization, and technical improvement, to tasks that generate even more added value. 

“Does this software have all the tools that my traditional software has? Will I lose analysis quality?” 

It is quite true that the first version of Dynamox’s software, prior to 2019, lacked more expert tools for analysis. However, little by little, updates were made, with the addition of new analysis tools, new graphics, new dashboards, and so on, always listening to our partners and customers. 

No one is born great, right?  

And these frequent updates are one of the biggest benefits of a cloud platform, because the updates are transparent to the users, that is, there is no need to download a new program, a new update, or pay for a new license. 

Back to the question of tools, today, the Dynamox software has several vibration tools capable of supporting even the most demanding analysts in an assertive diagnosis. To name a few:  

• Telemetry with collections up to 1 in 1 minute with maximum frequency of up to 13 kHz;  
• Banded trend graphs with alarms; 
• Spectral Envelope; 
• Circular waveform; 
• Autocorrelation; 
• Cepstrum; 
• Orbitals; 
• Cascade of all spectral graphs; 
• Bearing database for model registration; 
• High-pass, band-pass, low-pass and center-frequency filters; 
• Various metrics: peak, peak-to-peak, rms, kurtosis, crest factor, crest plus factor. 

In addition, the system has an automated detection module, dashboards for visual management of the maintenance processes and integration with several platforms. Another point to comment on is the integration with the system’s sensitive module, responsible for saving all the records of field inspections made by the system’s users via Mobile Application. 

“How are wireless sensors calibrated? What ensures that they will be generating reliable data?” 

Wireless sensors, because they are easy to install and are usually fixed to the machines, characterize a new reality in terms of quantity, that is, it is common for companies to adopt them massively with the installation of hundreds and thousands of sensors. Therefore, it is highly impractical to periodically calibrate each one of them, as is done with offline collectors. 

However, the good news is that for the technology used in Dynamox sensors, which uses MEMS capacitive accelerometers with digital output, this periodic calibration is not even necessary. 

All sensors present in the DynaLoggers (Dynamox’s data loggers), whether the accelerometer or temperature sensor, are calibrated by their manufacturers, that is, the devices are already calibrated in the production process. In addition, the manufacturers of the MEMS accelerometers used in the DynaLoggers correct the gain and sensitivity of each accelerometer with compensation routines stored in the internal memory of the sensor. Each time the device is triggered, the compensation values are loaded, obviating the need for subsequent calibrations. 

Another point is that the DynaLogger goes through checks within our strict quality process, where Dynamox is ISO 9001 certified. 

MEMS technology has great reliability with respect to drops and impacts on the sensor. Some studies show that the most common failure mechanism in MEMS accelerometers is caused by fatigue, which means that device degradation occurs most commonly due to sensor usage issues. Research also shows that the mean time to failure (MTTF) due to fatigue effects of the mechanical elements of a MEMS accelerometer is about 1.9×1081 s (worst case), which indicates that MEMS sensors have a high resistance to mechanical fatigue. Even under accelerated degradation conditions (at high temperatures, frequency, and amplitude), the estimated failure rate is little compromised. Therefore, based on several robustness studies available in the literature and practical validation with our customers, it can be stated that with the estimated lifetime of around 5 years, a DynaLogger does not change its response within this period. 

Proof of this is the graph below of the frequency response of a DynaLogger that was tested before field installation, soon after it was manufactured (blue line), and then retested years later, with various marks of use (image to the right) on the curve highlighted in dotted red. 

Predictive maintenance analysts and other industry professionals have already pointed out the advantages and benefits of implementing wireless sensors to monitor assets. Joel Nunes, vibration specialist at Dynamox, states: 

“In the more than 30 years that I have been in the field of predictive maintenance, I have used many types of vibration collectors. These wireless monitoring technologies have been a pleasant surprise and have been great allies in increasing asset security and reliability. For some years now, I have been dedicating my efforts to the evolution of technologies in this area with Dynamox.” 

And finally, Antonio Marcos Silva, vibration analyst at Alcoa, complements: 

“Wireless sensors have been changing the culture of my workplace. Simple, robust, low-maintenance devices that provide democratic information without losing quality and reliability. A solid step for industry 4.0. Today, I use the Dynamox system in my daily routine and one of the main gains of this system is the removal of the inspector from the risk area, allowing more time for assertive analysis and, consequently, improving the results for the company.” 

Keep browsing our blog and check out success cases with DynaLoggers installed on industrial assets.