I came across a website, http://www.phaseback.com, that has a device called a Phaseback VSGR where in addition to voltage stablization they make the claim that it prevents arcing ground faults thereby reducing the potential for arc flash by over 85%.

I am wondering what other's think of this and I have included the website so people can review for themselves.

By including the website, I make no claim or endorsement of this product.

Thanks Barry.

I was contacted directly by them last week so I am also curious about what others think.

I've seen many wild claims of how much eliminating arcing ground faults eliminates arc flash. The claims I usually see are 90 or 95% though. 85% seems awful low. IEEE Standard 493 (or whatever the 3000 series number is now) lets just say Gold Book has tables of how many arcing faults are phase-to-phase faults and how many are ground faults and the numbers are significantly lower than the purported number of faults that would be eliminated. However there is a problem with these numbers. Most of the time, ground faults rapidly escalate into full 3 phase faults. That much is clear from the open literature on arcing faults. In fact it happens within 1 or 2 cycles so it's almost instantaneous. If we were to examine the equipment after the fact, we'd see evidence of a 3 phase arcing fault. So the post mortem data used to develop IEEE 493 is clearly going to be skewed towards 3 phase arcing faults where the reality is quite a bit different.

Unfortunately though I can't point to a single well documented source suggesting what the real ratio of arcing faults (ground faults to everything is) actually is. All that I can say with any certainty is that using high resistance grounding MASSIVELY reduces the damage from arcing faults to the point where sometimes it is challenging to figure out what is wrong in the vast majority of failures. But I can't generate statistics on this.

As to the rest of the claims...they don't really ever get around to explaining it. It sort of sounds like a DSTATCOM or some similar FACTS device. They are pretty good but not that good. A quick scan of IEEE Xplore with the terms from the ads don't give any articles discussing it. I didn't see any patent numbers so no way to check there. I've always felt that something like a DSTATCOM long term is probably the way to go but the price tag is so incredibly high that it's not going anywhere any time soon for anything but the most specialized situations.

Hello everyone,

My name is Bill Hinton, Director of Engineering at Applied Energy, LLC, the company responsible for the development of the Phaseback Voltage Stabilizing Ground Reference (VSGR).

As Jim stated, I had reached out to him via e-mail on June 13th, 2017 to gauge his (and possibly the Arc Flash Forum’s) interest in the VSGR. Because I was unsure whether the Arc Flash Forum community is tolerant toward direct promotion or advertisement, I chose to wait until I received word back.

I have just discovered this thread this evening, and I am excited to address the concerns stated by PaulEngr, and additionally, provide some information for any other readers who may be interested.

I would also like to thank Jim Phillips for providing the opportunity for this discussion to take place, and for the open-minded nature of the comments received here.

First, I would like to give some background to the development of the product discussed herein.

In 1969, I started my career as an electrician. One of my first jobs involved working in power system maintenance. Today, I am still involved with power systems and power quality.

In 1993, I developed the first prototype leading to the Phaseback VSGR to prevent motor burnouts caused by arcing ground faults. We had 24 motor burnouts in 3 months. In the two years following the installation of the VSGR prototype, only two motors failed. Both failures were the result of the motor being inadvertently filled with water.

To be clear: the VSGR will not keep the water out, it won’t keep the drive coupling lined up, and it won’t clean particulate dust out of the fan, but it will prevent motor winding failure caused by voltage spikes and arcing ground faults.

In 2002, Applied Energy, LLC received patent rights (patent no. 6,888,709, see https://www.google.com/patents/US6888709) for the Phaseback Voltage Stabilizing Ground Reference (VSGR). At the time of patenting, it was described as an Electromagnetic Transient Voltage Surge Suppressor (EMTVSS). Upon the recommendation of the IEEE, the EMTVSS was renamed to the VSGR.

Next, I would like to address some of the points made by PaulEngr.


According to the arc flash software reference manuals, 85 to 90 percent of line-to-line faults start as phase-to-ground faults, also known as single line-to-ground faults. This is correct, as we are using the same data as the IEEE. We obtained the figure of 85% from a 1979 study, as referred to in the IEEE gold book that you had mentioned.


This is precisely why the VSGR’s original intent of design was to prevent ground faults. We are in agreement that most three-phase faults begins with a ground fault. Because the VSGR prevents the first arc to ground, it prevents the air from ionizing (becoming conductive), which prevents phase-to-phase faults.

To be clear: you can still drive a fork truck over an extension cord, or stick a screwdriver into a live circuit -- the VSGR won’t account for the remaining 10 to 15 percent of the causes arc flash!


While it’s true that a high resistance ground will limit ground current and reduce damage from arcing faults, it does so in a wasteful manner. By draining excess current to ground, a typical energy cost is incurred of $25,000 to $50,000 per year per 2,000 kVA transformer.

By comparison, the VSGR does not drain the capacitive energy to ground. Instead, it redirects the energy into the capacitive charge to balance the phase voltages.


The VSGR is designed to interact dynamically with the power system. It connects in parallel. It does not conduct or handle any load current. The VSGR causes a phase voltage correction as soon as the voltages are not equal to each other. This can typically balance the phase voltages within 1 to 2 volts using only a few milliamps.

Let’s do a comparison between a MOV-based TVSS, which tries to pull down the source voltage, causing tens of thousands of amps of noisy current to ground. The VSGR simply balances the load voltage, which takes milliamps of current instead of thousands of amps of current. The VSGR simply balances the load voltage the instant an imbalance starts to occur.


One major difference is that the VSGR does not compensate for poor power factor by the use of capacitors or solid state devices. Capacitors typically last 10 to 15 years, while the earliest prototype of the VSGR from 1993 is still in use today.

The VSGR is categorically different from a DSTATCOM or similar devices: the VSGR is a compensator of poor power quality, without the need for capacitors. In fact, the VSGR cleans up noise and disturbances caused by DSTATCOM (and other VAR compensating systems).

The VSGR is a purely inductive device, which operates at the speed of current flow. It simply balances the phase voltages with respect to ground under all conditions, including power failure, in which it provides a stable shutdown of equipment.


Our device currently holds a patent under #6,888,709. This patent number is described in the following link to the patent details sourced from Google: https://www.google.com/patents/US6888709



I believe the DSTATCOM’s design is excessive for the function it serves, and so too is its cost. Thanks to its elegant design, the Phaseback VSGR typically provides a payback of less than one year, and presently carries a 50 year warranty.

For additional information, I have attached a set of links pertinent to the VSGR and its benefits, including a test indicating its ability to prevent most arc flash events.

Again, I would sincerely like to thank the members of the Arc Flash Forum for this opportunity to elaborate on the design, function, and benefits of the Phaseback VSGR.

Questions, comments, and inquiries are welcome via this thread, or by my contact email at the bottom of this post.


Respectfully submitted,

William Hinton
Director of Engineering
Applied Energy, LLC
http://www.phaseback.com


KEMA Laboratory Arc Flash Test Video
https://www.youtube.com/watch?v=BXoG-NZqb7E

KEMA Laboratory Arc Flash Test PDF
http://www.phaseback.com/wp-content/uploads/2017/03/17013-k-phase-to-ground-overvoltage-withstand-borg-general-il-report-3633-ver-18.pdf

Phaseback VSGR 2017 Brochure
http://www.phaseback.com/wp-content/uploads/2017/03/a-new-vsgr-brochure-1-5692-ver-6-2325-ver-13.pdf

Benefits of Phaseback
http://www.phaseback.com/wp-content/uploads/2017/03/Benefits-of-Phaseback.pdf

Applied Energy “Critical Power” Presentation Video
https://www.youtube.com/watch?v=QFlucnojOsg

A couple things here. First the charging current in ANY grounding scheme which consists of the insulation in a 2000 kVA transformer and the grounded side will be about 1 A @ 600 V, or 2 A at 4160 V using the standard rules of thumb. Using 4160 V and $0.10/kw-hr, I get about $12,500/year in electrical costs. The loss exists whether the transformer is solidly grounded or ungrounded. The issue isn't magnitude. It's not $25-$50K except above 10 kV where high resistance grounding can't be used. It's the idea that charging current goes away if somehow things are "balanced". Parasitic capacitances exist always and can only be decreased with a smaller physical system (reduced surface area) or decreased insulation thickness (not really practical).

Second, I've looked at the patent. It shows a wye-delta transformer with the delta side having a single resistor in one of the delta legs and the other two shorted together. My immediate thought is that this is really similar to a high resistance grounding system for ungrounded deltas where you use a delta-wye transformer with a resistor in the wye leg, except that the transformer is "backwards". I'm really going to have to think about this in terms of impedance's but I swear I had one of these as a test or homework problem in school.