AI Is Fundamentally Changing FLS/FI Service

Picture This:

Imagine your company’s best onsite service techs. Picture how busy they are rushing from site to site, noting symptoms, prescribing fixes and installing replacement parts. Every day they are adding to a catalog of causes and effects, symptoms and solutions, fringe anomalies and their root causes. Every day they are on the job they become more effective and more valuable.

Now think of your most junior tech. Skilled? Yes. But that technician just doesn’t have the database of experience to pull from, and it will take years to amass the skills of your most valuable techs.

What if you could have that experienced tech at every one of your ATMs 24/7 – 365? What if every time a new symptom and solution popped up the information passed instantly to every single clone of your best technician? And what if the diagnosis of the problem was happening instantly without a service call even happening? Now, one more, what if the knowledge of that best technician was shared across your entire company from service managers making hiring decisions to purchasing teams deciding what replacement parts to stock? This is what Artificial Intelligence is bringing to the ATM market today.

The Future is Here

Voltonix has worked with service departments across all kinds of electromechanical equipment manufacturers for years, and this is a pivotal moment. We are all standing on the line of the foundational shift from reactive to proactive service. That is, Artificial Intelligence is changing the world around us. It’s not changing only video games and chess matches but also the way we do work, and the way enterprises make decisions.

AI is an elastic term and means different things to different people. Some more well known examples include Log File or Call Analysis, IoT Data, Digital Twins and Rich Sensor Data. It is the last one – Rich Sensor Data – that is both cost effective and transformational to First Line Service Organizations. The data provides real-time actionable insights with anomaly detections, and it learns and understands what is important as time goes on. It is also retrofittable and allows for cross platform implementation.

Voltonix is partnering with Sigsense Technologies on a wall-to-wall AI branch solution that uses Rich Sensor Data and requires only one sensor between the wall and the plug for each ATM, Cash Recycler, etc. An FLS partner recently told Voltonix:

“This is fundamentally going to change the DNA of our business.”

The solution eliminates mistakes in the diagnostic process and dramatically shortens it. Technicians would have the right part to fix the problem the first time on site. Real first call resolution is within reach.

Getting Specific with the NCR SDM

Inside the ATM ecosystem the NCR SDM cartridge serves as a specific use case and illustrates the agility of the solution. The SDM cartridge holds three bands that peel currency from the deposit. It relies on friction and tension and is generally a filthy component that can often jam bringing the ATM down. So, how does a remote computer with the assistance of only one external sensor alert a service organization to a jam in that specific section of the ATM? Or better yet, how can we tell that the cartridge is wearing before it actually fails and causes downtime?

The sensor provides a window into the machine’s entire electronic power draw. Through this we can see exactly which components are being activated and the sequence in which they occur. Sigsense’s Deep Learning algorithm takes that Rich Sensor Data and understands what a good deposit looks like versus a failed one. It is intelligent enough to correlate the jam signal with previous observed signals to alert technicians to the jam’s exact location. Rather than a technician responding to a general “deposit jam service call” the tech is dispatched to address the exact problem the first time out.

Through cumbersome log file analysis some Service Orgs perhaps can tell where the jam is, but the Deep Learning differentiator comes via correlations over time. The Algorithm understands and tracks when the SDM fails to strip the bill two times but then succeeds; maybe tomorrow the deposits fails three times before a successful sort.
In a log file system these ultimately successful deposits probably do not generate alerts. But with a Deep Learning application we can tell that the unit is entering a failure state by the increase in the frequency of almost failed deposits. That is, a non-catastrophic event can be flagged as an indicator of a future failure and thus a service call. Pattern matching over time empowers the unit to make predictive assumptions based on previous observations.

AI On the NCR S2

The same observations are simultaneously done with an S2 dispenser. Failed picks are easy detections as are the alerts, but the AI digs deeper. Typically, the S2 does not suddenly just stop pulling bills; it goes through iterations of increased rejects over time. Maybe it is a vacuum leak, or maybe it is bad currency. Each potential scenario looks slightly different to the algorithm. These observations are pattern matched to deliver prescriptive alerts for preventative maintenance. With enough data, we can even estimate time to failure.

The good news is to roll this out you do not need deep OEM pockets or specialized humans. In many cases, you do not even need a year’s worth of carefully organized log data. Deep learning, sensor-based implementations learn in real time, and the return on investment scales with the amount of data observed.

Getting Started

A number of companies are patching data solutions together to try to get ahead of the curve, but they are often cost prohibitive and lack the granularity and nuance that deep learning and Rich Sensor Data bring. Your data should be working for you already, and with this approach, it will work for your entire organization and not only your most valuable service technician.

A New Product Rollout Disaster

Imagine this: Your company rolled out the latest and greatest product that will finally allow you to compete head to head with the market leader. Your biggest customers have become your medium accounts as larger players in the market switched to your platform. The growth curve is looking exceptional, and expansion is on the horizon.

And then it happens…

Your service department is suddenly swamped with a series of issues from the new product; three distinct error codes seem to be bricking the machines. As a result, tens, then dozens, then hundreds of replacement units are being deployed all over the country. Your supplier has no answers, and your service team cannot nail down a single source of failure. Now you are rapidly burning through all of the good relationship equity that this product launch afforded you.

Voltonix was brought to the front lines of this nightmare scenario and assisted its client in this potentially catastrophic, company ending battle.

The Problem:

The product involved a chip-based magnetic card reader that could also write to the EMV or chip. The chip lost power during the card read process, and the machine was unable to provide power to the chip on the card… ever again. A bricked machine that costs tens of thousands of dollars does not make for a happy customer base. What’s worse, word travels quickly in this industry.

The Strategy – Protect:

After Voltonix conducted a deep-load analysis and profiled the device’s DC loads, it was determined that the culprit might be insufficient voltage getting to a component. Furthermore, dirty power sources might also have been corrupting a board. While the manufacturer’s engineers continued to troubleshoot additional hardware fixes, Voltonix helped the client deploy a statistically significant number of low impedance isolation transformers to test power as a variable. In a perfect world, this would be the end of the story. Problem solved – wrap it up with a self-congratulating paragraph and high fives all around. But it wasn’t.

The Result:

While the low impedance isolation transformers did reduce the failure rate by a full 10 percent, half of the units were still failing. The engineering team determined that a combination of replacement parts, including one addressing electrostatic discharge, completely eliminated the problem. The incoming cards carried a small static charge into the system and nuked the board responsible for writing to the card. To solve this, a brush could be installed on the card input that would dissipate the charge. Now the client needed to deploy this 40-minute hardware retrofit to 1,600 units across the country.

The Strategy II – Prepare:

The Voltonix site preparation program allowed us to deploy an army of skilled labor nationwide within days. By adapting the workforce to perform this very specific set of tasks, Voltonix was able to rapidly deploy a complicated hardware retrofit to hundreds of machines. Here’s how we did it.

The Real Solution:

First, we went onsite with the manufacturer who was rapidly retrofitting the existing inventory at the client’s warehouse to learn the process and setup the logistics to deploy the kits to our workforce. Next, we trained our project managers on the procedure and developed the full scope of work and deliverables for each site. We created an iFixit-style walk-through webpage as a reference for technicians to review before they went onsite. Finally, we managed technician check ins, troubleshooting and deliverable submissions from our HQ. We were able to launch this program within days of the discovery of the final fix.

Conclusion:

A valued client faced a perilous situation that could have sunk this vertical within the company at best and the entire business at worst. We were fairly confident that our “Protect” P would solve the problem. It was something; but it wasn’t enough. This might have been the end of the line for some consultants. But Voltonix is dedicated to discovering solutions and solving problems. By working closely with both the client and their supplier collaboratively, we helped implement a fix across a widely dispersed deployment of assets.

The client was satisfied, and the client’s customers saw them as responsive and aggressive in their remediation of a serious issue. The client’s supplier saved face by discovering a solution and funding the remedy. It was a win – win – win scenario. The extended result for Voltonix was a new program: Smart Hands. Voltonix now offers ad-hoc break fix services to OEMs anywhere in the country at extremely competitive rates. When phone support isn’t resolving a site issue, and it isn’t feasible to fly a burdened employee out, Voltonix Smart Hands can work independently or with your service team to get equipment up and running again.

 

Executive Bio: Andy Steele

Andy Steele serves as the Vice President of Strategic Operations for Voltonix. It is Andy’s responsibility to ensure the company’s day-to-day operations run smoothly while gracefully navigating any unforeseen bumps in the road. He works closely with all external company principals and owns the company’s customer service process, supporting it from initial outreach through onboarding. He believes deeply in single-point accountability and the need to first listen and understand a customer’s goals before offering a solution.

He says a positive customer experience is critical to the establishment of long-term relationships and thus the health of the business. “We have a real focus on quality and the need to make our clients thrive in front of their key relationships,” he says. “By going to market with ‘The Four Ps’, we are in a unique position to help companies save money across multiple verticals while also helping them to deliver on their own vision.”

Andy earned his Bachelor’s degree at the University of Montana and his Master’s in International Affairs at Ohio University. After living and working abroad for over ten years in Thailand, Indonesia and Afghanistan, he joined Voltonix in 2016.

Andy spends his free time chasing warblers and other avian oddities while keeping tabs on a precocious toddler named Emma Rose.

 

 

Executive Bio: Ken O’Connell

Ken O’Connell serves as the Vice President of Business Development for Voltonix. It is Ken’s job to ensure Voltonix is connecting with the companies looking to aggressively tackle service burden, reduce warranty exposure and increase reliability across their manufactured products. Ken helps the Voltonix team work closely with executive, service and engineering teams to implement key initiatives around artificial intelligence for predictive analytics, power protection and end user install site preparedness. He helps marketing and sales teams within these OEMs introduce products and services to their customers.

Ken believes simplifying the complexities around AI and electrical engineering problems helps OEMs drive toward the implementation of solutions. He says, “Many OEMs have 2020 and 2021 initiatives around implementing deep learning and artificial intelligence platforms to reduce service costs and predict failures. Often they struggle with the resulting science experiments that don’t lead to actionable services. We help introduce much more simple, cross-platform solutions that drive toward specific and measurable service cost reduction from day one.”

Ken studied Electrical engineering at the Ohio State University. He’s spent over 6 years with Voltonix working with OEMs in the ATM, clinical diagnostic and 3D printing markets.

When he’s not crunching algorithms, Ken spends his time with his wife corralling his two rambunctious boys on the shores of the Gulf Coast.

 

 

Predictive Analytics Could Have Prevented Disaster – Heartbreak

predictive analytics artificial intelligence

On the weekend of March 3rd 2017 a cryogenic storage freezer failed. 2,100 embryos and eggs were destroyed and hundreds of families were left devastated. It took only a few hours for the finger pointing and allegations to begin. The Ohio fertility clinic blamed the equipment manufacturer; the OEM blamed the hospital. The families, who trusted their potential progeny to be stored, had little recourse but to file lawsuits. What could predictive analytics via artificial intelligence have done to prevent this? Let’s dig in to the details.

 

What happened?

After a lengthy investigation it was determined that the storage tank was having trouble for weeks. An alarm system had been turned off failing to indicate that the tank’s temperature began to rise. The tank was also undergoing preventive maintenance at the time because of a problem with a system that automatically fills the liquid nitrogen, which keeps the embryos frozen. The manufacturer of the tank, Custom Biogenic Systems, said it didn’t have anything to do with the remote alarm system being turned off. It said the tank functioned properly by indicating a high-temperature condition and activating a local alarm. For potentially weeks, that alarm was alerting staff locally that temperatures were rising out of spec. The staff eventually became annoyed and disabled the alarm. University Hospitals said it doesn’t know who shut off the remote alarm, which should have alerted staff again to changes in the storage tank’s temperature on the weekend of March 3 when no one was at the lab. Because that was turned off and no redundant alert system was in place, 2,100 embryos and eggs were lost.
 

Multiple Failure Points

  1. Preventative Maintenance

    It’s fairly clear that the tank’s trouble began with a failure to carry out standard, necessary preventative maintenance. After 5-7 years of service life, the Custom Biogenic Systems tank was known to experience ice build up on the solenoid valves that automatically refill the nitrogen. A defrost cycle was necessary to prevent the valve from sticking. The defrost was not performed and the University Hospital staff was filling the tank manually.

  2. Local Alarm Only

    When the tank temperature rose to an alert status, the understaffed hospital clinic was closed for the weekend AND a potentially non-clinical staff member silenced the alarm. Critical alarms with no centralized reporting can (and did) result in catastrophic failures.

  3. No Reporting to the OEM

    Though Custom Biogenic Systems was not named in the lawsuit and appears to not be culpable, there was likely significant damage to their reputation in the market. The UK issued a warning after similar incidents had come to light. Googling the trade name results in pages of headlines about their relation to the destroyed embryos. There is little indication, however, that the University Hospital system is the one being held accountable unless one clicks through and reads the entire article.

 

What could have happened?

If the OEM had central monitoring of its deployed assets that indicated whether preventative maintenance procedures (like the defrost) had occurred, it could have alerted the hospital that best practices were not being followed. Furthermore, if the OEM had been able to monitor the individual components of its assets, they could have known a failure was imminent. A stuck valve has a very pronounced electrical signal and can fairly easily be identified as non-nominal behavior.

predictive-analytics-for-precision-diagnostics

Predictive Analytics via Artificial Intelligence is the Answer

Sigsense allows equipment manufacturers to unobtrusively monitor deployed assets at the component level. An artificial intelligence algorithm constantly monitors the behavior of the device and compares it to non-nominal behavior. If maintenance procedures are not completed or motors or valves deviate from normal alerts are generated. The problems are then addressed before thousands of headlines are published. It’s true preventative maintenance and in this case, a really great reputation management tool.

Sigsense allows OEMs to understand why components fail before they do. By implementing remote monitoring capabilities OEMs can reduce service calls, downtime and reactive maintenance costs. In high-stakes applications like this, Sigsense could have enabled this manufacturer to protect its customers from a devastating disaster.

 

What is the Best UPS for 3D Printers?

One of the most common questions we get at Rapid3D and similar trade shows is: “What is the best UPS for 3D Printers?”. Like most things, it depends. A $300 Monoprice Maker Select probably isn’t going to be found in the wild on an online sine-wave output UPS. That said, there are a few questions to ask yourself when pairing your industrial 3D printer to a reliable UPS.

What problem am I trying to solve?

Power problems originate from 2 sources: Inside your facility and outside:
best ups for 3d printers problem sources

It’s easy to think that most power issues are coming from that power plant on the left, right? The lights flicker or you’re searching for candles; this is the most visual representation of power issues, but it’s only a small part of the problem.

3d printer problem sourcesSo if the printer is disposable and all we care about is occasional downtime from a thunderstorm or a car careening into a telephone pole, a big box UPS is probably fine. If the 3D printer is an investment or it produces critical prototypes or products, we have to dig deeper.

What is True Power Protection?

Power Protection keeps the power pumping when the power goes out AND protects the device from non-nominal power from within the facility. Even dedicated circuits with isolated grounds often share neutral wires with additional circuits; until 2011 the NEC allowed it and even still, most inspectors don’t know to look for it. From the NEC code book:
So if your machine is disposable or your installation site was built after 2011 AND you know for sure the electrician did not share neutral wires, you might be ok… unless your device has a connected ethernet port. Assuming the IT rack has a different ground location from the circuit feeding your printer, you probably have a ground loop. Ground loops cause communication issues and connectivity problems frequently; these symptoms are rarely traced to the power problem causing it.

True power protection is prepared to address all sources of electrical problems:

So, What Do I Need?

If you really want the best UPS for 3D printing, it needs to have all of these things:

1. Isolation Transformer

A low impedance isolation transformer creates a copper break between the incoming power and the printer. Damaging transients, harmonics and ground loops will never get through.

2. Battery Back-Up

To protect against power outages and voltage sags/dips, you need batteries in-line to keep the power flowing.

3. Sine-Wave Output

Don’t expect the SMPS to auto-magically rectify a cheap square waveform generated by a sub-par UPS. The fast rising and falling edges of the “modified side-wave” create noise that will be coupled to the DC busses. It is also a stress riser for capacitors and silicon components since there is a resulting current spike. In English: It is shortening the life of the your printer while also generating noise which can cause lock ups. A Sine-Wave is the same type of power that comes out of the wall. The UPS should be proving it too.

4. Noise Filter

Every UPS on the market lists “noise filter” as a feature. The reality is, unless the impedance is known, a noise filter cannot be attenuated to be effective. An isolation transformer creates predictable impedance so an effective noise filter can be implemented.

*Bonus*: Surge Protection

Many UPS systems advertise this as a primary benefit but most every consumer grade UPS will be destroyed with an inbound strike. The printer will be protected but the voltage was just shunted to the ground. If there are any other unprotected devices on the circuit, they are toast. An isolation transformer can absorb up to 6000V @ 500A non-destructively. This means the printer is protected, so is your UPS and everything else down circuit.

Standard UPS systems don’t do anything to impede surges below 300 watts.

So, What is the Best UPS for 3D Printers!?

Ultimately having the best UPS for 3D printing is not life or death (like it is in some cases). We’ve worked with some of the biggest 3D printing manufacturers in the world to answer exactly that question. The answer is a UPS that has all of the above and is sized to handle both the inrush and sustained load of the printer. We’ve developed 3-phase solutions with voltage step-downs that accommodate the 400V input required by some German-based manufacturers. We’ve private labeled solutions for OEMs to market the UPS as a single “Power Protection Solution”.  Whether you’re simple selling desktop 3D printers or large frame 3-phase 3D printers, we can help your team develop, field trial, market and sell a solution that will impress your customers. It’s what we do. Give us a shout and we’ll figure it out.

Voltonix – CUSI – One Became Two

Here We Grow Again

 

What Happened?

We are excited to announce that Customized Uptime Solutions, Inc. split into two separate entities in 2018 to create a clear distinction between its lines of business. The new entities are CUSITech LLC, at www.cusitech.com and Voltonix LLC, already active here. Both companies will continue to operate out of the headquarters in Westerville, OH.

What’s Different now?

CUSITech provides national onsite electric, structured cabling and smart hands support to help companies achieve smooth implementation on a broad geographic scale. CUSITech provides its services to companies that need a simple new electric or data circuit to very complex projects that require trenching, boring, 1,000’ of feet of conduit and major system upgrades. It also provides turnkey installation services for applications that require electrical and structured cabling infrastructure as part of the installation such as HVLS fans, kiosks, dock and door as well as electric car charging stations. CUSITech helps streamline reliability, simplify complexity and provides single point accountability. It is the trusted national partner providing consistent onsite site prep services.

Voltonix LLC provides power quality consulting and hardware and software technology to reduce electro-mechanical equipment downtime. Voltonix provides its services to companies that manufacture and/or service equipment such as medical devices, lab instrumentation, 3D printers, POS systems, ATMs, kiosks, heavy industrial presses and lasers and medical imaging equipment. The proven process and patented technology is paramount in reducing service spend and helping customers increase revenue. The return of investment is less than 90 days in most applications.

What does Voltonix Stand For?

Power is complicated. It’s a major variable that has qualitative and quantitive effects on our customers and partners. Our first goal is to make sure our products and services are effective. Our field trial process makes this free and painless. One of our customers once told us “In god we trust, all others must bring data”. Our goal is to create demonstrable results so that our partners can calculate exactly what our products will save in reduced service costs. We believe in optimizing uptime and empowering reliability.

What will Change to You?

In short, our email signatures and our website. Our team will work with the contract administration departments over the next 8 weeks to update all of the important documentation such as Supplier Agreements and Confidentiality Agreements. Give Craig, Ken or Andy a call or email if you have any questions.

Power Conditioner vs Voltage Regulator

power-conditioner-vs-voltage-regulator

Power Conditioner vs Voltage Regulator: The Ultimate battle in Power Quality gear. To understand the difference we must take a look at some history and the reason each of these important power protection components evolved. Let’s take a deep dive:

Power Conditioner vs Voltage Regulator Introduction

Since the advent of electronic systems, electrical power related disturbances have had the ability to destroy components, disrupt system operation and interfere with productivity. Almost everyone has experienced the effects of power problems at one time or another, and it’s a common belief that system failure is due to voltage “sags” and “surges”. However, electronic technology is continuously evolving, and it is important to recognize that this evolution has changed the way systems respond to power disturbances. The advent of switch mode power supplies (SMPS) was specifically implemented to address these issues. The adoption of the SMPS replaced the linear power supply opening up modern computers to a fatal flaw.

The Evolution

When John Atanasoff and Clifford Berry invented the first digital computer in 1939 at  Iowa State University, they built a machine that relied on vacuum tubes for the fundamental logic circuitry. These were high voltage, low current devices that were powered by a basic linear power supply. From the ENIAC, EDVAC, and UNIVAC systems that followed to the more familiar systems of the mid-1980’s, little change took place in power supply design. By the late ‘80’s, however, engineers had begun using large numbers of integrated circuits which themselves were being built with increasing numbers of transistor junctions. The result was a “low voltage” computer, which used substantial amounts of current. Linear power supply technology of the time was inefficient. A power supply capable of meeting the current delivery requirements of the rapidly growing computer circuitry would be significantly larger than its predecessors. Designers were striving to make computers smaller and, larger power supplies were just not compatible with this goal. The result was the introduction of the SMPS. This design eliminated the 60 Hz. stepdown transformer and series regulator section in favor of a pulse width modulated, high frequency circuit capable of rectifying line voltages down to usable, well regulated dc power for the computer’s logic circuitry.

Fundamental Differences

This technological change is responsible for some fundamental differences in the way systems respond to power problems. The linear power supply rectified incoming line voltage and supplied power to the logic circuitry through a series regulator. The range of this regulator was limited, however and an input voltage that was too high or too low would quickly result in problems. Low input voltage would cause the supply output to “foldback” or drop below the operating tolerance of the logic circuit. Input voltage that was too high would activate the power supply’s “crowbar” circuit. In the process of protecting itself, the power supply output would again fall below the operating tolerance of the computer’s electronic circuitry. Because line voltage variations are frequent, sags and surges were commonly the culprit in early electronic system failures. Dedicated electrical circuits were the first line of defense against this condition, and if ineffective, a voltage regulator was normally specified.

Switch mode supplies are very different. The series regulator has been eliminated along with the input stepdown transformer. Switch mode power supplies consume current from the AC power supply for only portions of each power line cycle. Not only are switch mode supplies considerably smaller and more efficient, but they are largely immune to voltage sags and surges. An explanation is found in the way the system operates.

Duty Cycle Is Everything

Because the switch mode supply draws current for only a brief time period, much can occur to the line voltage during the time the switcher is “turned off” with little effect on its operation. If line voltage sags or surges during the time the supply is “turned on,” the supply compensates for the variation by adjusting its duty cycle or the time period over which it operates. With less peak current available, the supply compensates by drawing current for a longer period of time. The power supply’s voltage outputs still supply well regulated +5 and + 12 volts under full rated load.

Built In Voltage Regulation

The capabilities of switch mode power supplies with regard to voltage regulation problems are well documented. In fact, it is the inherent tolerance to such voltage variations that makes it possible to operate a modern system from a standby UPS in which the computer may operate completely without power for as much as 5 or 6 milliseconds while it is transferred to a battery powered inverter. Switch mode power supplies can be said to contain their own “built in” regulation capability. It is important to note that most voltage regulators can only adequately regulate down to 75% of nominal line voltage. Switch mode power supplies are naturally tolerant of voltages well below the regulation capabilities of most regulators.

Compatibility Issues Abound

The most popular types of regulators are tap switching autoformers and/or transformers and ferroresonant transformers. Regardless of the type, these regulators all accomplish their function by controlling the current flowing in an electrical circuit. This can have implications for the appropriate operation of switch mode supplies. Voltage regulators tend to be high impedance sources, which restrict the amount of current available to the supply at any given time. Under these circumstances, the switch mode supply can be “starved” for current and in the process cause significant voltage distortion on the output of the regulator. Significant noise generation may result, and there is conjecture in the industry about the stress placed on the supply by permanently altering its duty cycle. All these are compatibility issues of the first order. Voltage regulation is no longer necessary for switch mode technology. Eliminating the misapplication of voltage regulation technology will eliminate any concern for compatibility, too.

Appropriate Solutions

In the migration from linear supply to switcher, the input step down transformer was eliminated. In the process, the system’s natural immunity to common mode noise and high voltage impulses was totally lost. Today’s power protection solutions recognize that these immunities must be restored. An appropriate solution for modern systems incorporates a surge diverter, an isolation transformer, and a noise filter. These three elements work in concert with the natural voltage regulating ability of the switch mode supply to provide all the power protection elements necessary for modern systems.

Conclusion

Voltage regulators no longer provide any needed protection for modern computer systems. Their continued use is largely due to the industry’s failure in educating its customers about the power protection needs of modern systems. Solutions that include isolation transformers, surge diverters and noise filters are far more effective and do not introduce the compatibility issues that can create more power problems than are solved.

Neutral to Ground Voltage: What is it?

Most people believe that “power problems” start at the power company or within the transmission network. It’s true that brownouts do occur and cars occasionally careen off into a power pole; however, in the grand scheme of things, this is super rare. The most common power issue is caused by neutral to ground voltage and it’s coming from inside your facility. So what exactly is it? Where does it come from and how can we prevent it? Let’s get into the details.

Defining the Problem

Neutral to ground voltage is most often called Common Mode (CM) Voltage.  It’s measured between the neutral (white) conductor and safety ground (green or conduit) conductor of the electrical system. Common mode voltage can occur over a wide range of both frequencies and voltages. Neutral to ground events can cause some really serious disruption to the operation of microprocessor based equipment. In the old days, microprocessors used to be fed by large linear power supplies that did a fantastic job of eliminating Common Mode voltage. The tiny switch mode power supplies of today are great at regulating voltage but do very little to suppress Common Mode voltage. Microprocessors are constantly measuring logic voltages against the “zero voltage reference” of safety ground. Since all of a computer’s decisions are the result of discriminating one rapid changing voltage from another, ultra-clean and quiet electrical safety grounds are essential. The microprocessor expects to see very low (less than .5 volts) of neutral to ground voltage. When common mode voltages get out of this range you’ll see system lockups, communication errors, reduced operating throughput, unreliable test data, fragmented hard drives, and operational problems that cannot be explained or duplicated. Software developers and equipment manufacturers get fingers pointed at them, but the facility power is the source. Let’s look at from where in the facility these transients are coming.

Shared Neutral Conductors

Electrical Codes, let electricians “share” the neutral conductor… so they do. This practice allows a neutral conductor to serve three different circuits. On paper this look like the voltages would cancel out and everything would work in a state of total equilibrium. In real life, three-phase systems are not so tidy. Electricians may do their best to try and balance the currents in each leg, but it is nearly impossible to balance correctly.

Equipment like elevators, compressor and air handlers cycle in their operation while computers, lights, copy machines etc. are continuously turned on and off. These changing conditions create imbalances in the system. An electrical environment is very active and is guaranteed to make the balanced math fall apart.

So, what we get is neutral to ground voltage flow.

Load Balancing Difficulties

While changing load conditions make load balancing difficult, all the switch mode power consuming current in nonlinear “gulps’ from the power line makes it even worse. Even if an electrician managed to balance all three RMS phase currents, he will discover that current is still flowing in the neutral conductor.

This circumstance will occur in a modern facility even when good wiring practice and load balancing techniques have been observed.

Branch Circuit Length

Sue’s blood gas analyzer is on the opposite side of the building from the electrical panel. The 240V branch circuit feeding his device shares a neutral conductor with the refrigerator in the break room. Every time that DC compressor motor kicks on, a frenzy of transients are transmitted back to her Analyzer. The additional circuit impedance of the long branch circuit makes Sue’s issues even worse. Sue gets inconsistent results and blames the OEM. Three months later, the support staff is pulling their hair out trying to figure out the issue.

Induced/Conducted Voltages.

An induced disturbance happens through electromagnetic fields. That fancy inductive iPhone charger of yours is creating an electromagnetic field. Lightning, close physical proximity to motors or other devices with electrical windings can all cause issues. The common mode voltage disturbances that affect systems are produced by the systems themselves. “It’s coming from inside the house!”

Personal computers, copy machines, fax machines, laser printers, medical instrumentation, telephone switches, the point of sale systems etc. all are contributors to this effect of conducted neutral to ground voltages.

So what do we do about it?

Finding Solutions

Microprocessors are getting smaller, more sensititve and ubiquitous. Reduce the impact of common mode voltage is imperative. Here’s how to do it:

  • Use oversized conductors to lower impedance
  • Run individual neutral conductors to each circuit
  • Perfectly balance each circuit

OR

  • Use an Isolation transformer at the point of use

The most effective tool for control of neutral to ground and common mode disturbances is an isolation transformer. These allow the bonding of neutral to ground on the transformer secondary. That just means there’s full isolation from the building’s electrical system. This creates predictable impedance (almost zero) it is impossible to cause the voltage drop associated with long branch circuits. Isolation transformers eliminate the problems associated with common mode voltage. Service calls are reduced, uptime is increased and users are happy.

 

This is why there’s an isolation transformer in most every device we carry.

 

3 types of UPS Systems and How to Not Pick The Wrong One

types-of-ups-systems

There are three main types of UPS systems and each is intended to keep a device, instrument or computer protected from blackouts, brownouts and catastrophic events. Ultimately the job or any type if UPS is to protect your gear from one of the potential power issues out there. A full power quality solution requires a more than just a battery backup.


1. Standby UPS

A Standby or “Offline” UPS system’s load is powered directly by the input power. When the voltage becomes too high or too low, the UPS automatically switches to battery backup mode.

There is a transfer time that occurs to go between normal power and battery power. The switchover can take as long as 25 milliseconds (ms) depending on how long it takes the standby UPS to detect the lost utility voltage. The UPS is designed to power certain non-critical equipment like personal computers.

 

2. Line Interactive UPS

A Line Interactive UPS is similar to a Standby UPS but with the addition of a multi-tap variable voltage autotransformer that provides built-in voltage regulation – commonly called a buck/boost capability. The special type of transformer can add or subtract powered coils of wire, thereby increasing or decreasing the magnetic field and the output voltage of the transformer. Got that?

This type of UPS is able to tolerate continuous under voltage brownouts and overvoltage surges without using the batteries, which helps to preserve battery life. When the voltage is too high or too low for the buck/boost capability, the UPS will automatically transfer to battery power. There is a transfer time that occurs between normal power and battery power, however, unlike a standby UPS, the transfer time is very quick and should occur in less than 5 ms. This type of UPS is great for devices/equipment fed by a switch mode power supply (SMPS). The SMPS can easily tolerate the switchover.

 

3. Online UPS

An Online UPS provides a constant source of electrical power from the battery, while the batteries are being recharged from the incoming AC power. It uses a “double conversion” method of accepting AC input, rectifying to DC for passing through the rechargeable battery (or battery strings), then inverting back to the necessary AC voltage for powering the protected equipment.

With Online UPS systems, the batteries are always connected to the inverter so there is zero transfer time when an outage occurs. When power loss occurs, the rectifier simply drops out of the circuit and the batteries keep the power steady and unchanged. When power is restored, the rectifier resumes carrying most of the load and begins recharging the batteries.

Most UPSs below 1kVA are Line Interactive or Standby. An online UPS is for mission critical applications. Clinical, analytical, laboratory and uptime guaranteed IT hardware must be protected with a power conditioned UPS.

 

Picking the right one

Many consumer applications will tolerate an off-the-shelf big-box store UPS just fine. There can be compatibility issues with newer switch mode power supplies and the cheapest square-wave bypass UPS systems.