Does an isolation transformer improve a power cable?
In a post dated 12/14, I described how I built my DIY AC power cables. In evaluating these new cables over the first 100 hours, I am hearing parts in music I did not know where there--instruments are standing out in sharp relief with a more robust dynamic and improved clarity. All of this is coming through via Furutech's Ohno Continuous Cast copper, a brand I am not here to promote--rather, it is the one I chose to obtain a legitimate OCC material. These cables are feeding two ARC Reference 210's, modifed to 250's. But, what appears to make as important a contribution is what is feeding the AC cables their current--a large 240V/120V isolation transformer weighing 120 pounds and supplying 4000 watts of work to all of my devices via six outlets on the back. What I am understanding is that this thing provides a more ideal supply of current that is independent of the rest of the house and its appliances and devices. With all that is said about power cables and what they can and cannot do, depending on one's beliefs about alternating current, i.e., what is upstream, how could it matter, what about the rest of the grid, the last six feet is important, etc, I suspect that, in using a true induction transformer in this manner, the last six feet is the only six feet in my power supply, and this is why these OCC cables sound so stunningly good. Is this the purest AC energy pathway possible?
Thanks for posting page 10. It seems to lean toward "...a newly derived system ground." At any rate, I am very pleased with this product, and yes, the 1200C is plugged into the RM PRO. This is what Richard Gray calls their IsoGray configuration, which provides even more isolation to the front end. I have only my Wadia 861 CDP/pre-amp plugged into my 1200C. The Wadia is babied with an ideal power source in this way. The 1200C could easily support separate CDP/transport/turntable/pre-amp. I have another one in another room for my plasma TV and Blu-ray player and a pre-amp, and I plug that one directly into the wall, which also works for the 1200C. A small stereo amp is plugged into the wall. But yes, the best set up is the IsoGray. A lot of people don't like RGPC, citing bad results, e.g., stifled dynamics, but others have found them to be very good. Whether Torus Power or RGPC or another, best to have the 240V/120V models so you have a lot of clean power right up next to your gear. Then, it is only a short run with a great AC cord, and this is, in my recent experience, a breakthrough finding. Best Regards, Joe
I'm still not sure where this leaves us on the question of a separately derived power source or an isolated ground. 01-07-15: Jafreeman
The secondary of the isolation transformer of the Richard Gray RM PRO unit is a separately derived system. The RM PRO unit also provides surge protection on the line side of the primary winding.
Here is just a snippet from a book written by Henry Ott. Quote. "Basically, in the case of a separately derived system, we start all over again, as if it was the main service entrance panel and we create a new single point neutral to ground bond." End of quote.
Page 10 Quote. "| "Residential Power Distribution & Grounding - The Truth In residential installations, a dedicated electrostatically shielded isolation transformer will act as a buffer between the utility company electrical system and the protected electronics systems such as AV equipment, home theater electronics, automation systems, and data devices. These isolation transformers must be hard-wired by a licensed electrician. This transformer, when correctly installed, is an effective sink for the collective ground leakage current of multiple switch-mode power supplies found in almost all modern equipment. The AV and control system will benefit from the improved power quality, greatly reducing the effects of ground loops through having a single point source for power and grounding. An isolation transformer is a device that prevents power quality problems by galvanically isolating the load from the power source, and incorporates a new neutral conductor that is bonded to a newly derived system ground. This newly derived neutral to ground bond eliminates common-mode voltages at that point, which are usually the main cause of unreliable system operation, equipment failure and service calls." End of quote.
I suggest you start reading from page 8.
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The 1200 is the best item for an entire front end.
What are you plugging the 1200 into? The RM PRO unit?
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As for an isolated ground not sure what you are referring to. If you mean an isolated ground for bonding the new neutral of the secondary of an isolation transformer that is a No No. The neutral must bond, connect, to the main electrical service grounding system of your home. The neutral bond, connection, in your case is made through the safety equipment grounding conductor of your 10-2 with ground branch circuit wiring that feeds the isolation transformer. Another good reason you used #10 wire for the branch circuit. .
Jim, thanks for that in-depth manual from Exact Power. This should be enough info for anyone who wants to improve power to a system. I'm still not sure where this leaves us on the question of a separately derived power source or an isolated ground. I know the primary winding is grounded to my house via the supplied cord--not sure what the secondary winding can claim when there is an iron core to aid in the induction of the stepped down voltage made available at the six outlets on the back. I can only say that, having gone up the chain from several 400s, to the Substation to the RM PRO, improvements have been dramatic. The 400s are meant for front-end pieces only, not amps. The 1200 is the best item for an entire front end. There is a guy who occasionally runs an ad for a new 1200, sells them for around $950, sez he can't give the warranty, but guarantees it will work. He's the real deal--I have two from him--guy named William Loni.
Thanks for the clarification on the grounding of the Richard Gray RM PRO Unit.
The RM PRO is more than just an isolation transformer. Richard Gray RM PRO . . Here is a white paper from EXACTPOWER. (PDF). You may find it interesting reading. .
An isolation transformer creates a new separately derived AC power system that is independent from the mains power of your home's AC power system. 12-30-14: Jea48
Maybe I misread it.... 01-04-15: Scvan
Again,
Just to be a bit of naysayer/ clarifier the transformer does not "create" electricity as I have stated before. 01-02-15: Scvan
Exactly where in the sentence do I say an isolation transformer "creates" electricity? It does not . Post in question.
Are you saying an isolation transformer does not "create" a "separately derived system" as defined by the NEC Code Definition? Is your hang up the word create? When an isolation transformer is connected to a grounded power system because the secondary is not electrically connected to the primary, the secondary output will be floating above ground. The secondary is isolated from the power source that feeds the primary in so far as there is not a reference, difference of potential, voltage, from its' output to the power source that feeds its' primary until one lead, leg, of the secondary winding is intentionally connected, bonded, to ground. (Ground being the main grounding system of the premises' electrical service.) This leg becomes the The Grounded Conductor, the neutral. A new grounded power system is created.
Here is a snippet from a book written by Henry Ott. 3.1.6 Separately Derived Systems. Do you find fault with what Ott said? .
You are smarter than that. You know the definition of created.
If the voltage on the supply side drops it drops on the other side of a transformer. It isolated electricity it doesn't create it.
One side of the transformer has an electromagnet on it that created a field that oscillates at 60 hz. That field is transfered by the core to another set of wires that the field is inducted to. If electricity was truly being created, it would violate the first law of thermodynamics.
Definition of a transformer:
A transformer is an electrical device that transfers energy between two or more circuits through electromagnetic induction.
Transfer, not creation...
Isolation transformers block transmission of the DC component in signals from one circuit to the other, but allow AC components in signals to pass
hmmm... so if I have an AC noise or change in AC voltage will the isolation transformer let it pass or will it always be a perfect sinewave?
And for those that are excited about the idea of a balanced isolation transformer, from the NEC:
647.3 General. Use of a separately derived 120-volt single-phase 3-wire system with 60 volts on each of two ungrounded conductors to a grounded neutral conductor shall be permitted for the purpose of reducing objectionable noise in sensitive electronic equipment locations provided that the following conditions apply.
(1) The system is installed only in commercial or industrial occupancies.
Just to be a bit of naysayer/ clarifier the transformer does not "create" electricity as I have stated before. 01-02-15: Scvan
Scvan,
Other than you, who has made such a statement?
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Separately Derived System.
NEC 2011 Article 100 Definitions
Separately Derived System.
A premises wiring system whose power is derived from a source of electric energy or equipment other than a service. Such systems have no direct connection from circuit conductors of one system to circuit conductors of another system, other than connections through the earth, metal enclosures, metallic raceways, or equipment grounding conductors.
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The revised definition in the 2011 NEC defines Separately Derived System as: A premises wiring system whose power is derived from a source of electric energy or equipment other than a service. Such systems have no direct connection from circuit conductors of one system to circuit conductors of another system, other than connections through the earth, metal enclosures, metallic raceways, or equipment grounding conductors.
A separately derived system is a premises wiring system with no direct electrical connection to conductors originating from another system [Art. 100 definition and 250.20(D)]. All transformers, except autotransformers, are separately derived because the primary circuit conductors do not have any direct electrical connection to the secondary circuit conductors. Generators that supply a transfer switch that opens the grounded neutral conductor would be considered separately derived [250.20(D) FPN 1].
An Isolation transformers is a Separately Derived System.
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Separately Derived System. A premises wiring system whose power is derived from a source of electric energy or equipment other than a service. Such systems have no direct electrical connection, including a solidly connected grounded circuit conductor, to supply conductors originating in another system.
. .
Some examples of separately derived systems would include: Transformers, shown in photo 1, where the supply side is isolated from the derived side except by magnetic coupling Generators (motor, wind, or engine driven), one example shown in photo 2 and figure 1, where it is either a totally stand-alone system or is an alternate source of power and the grounded conductor (neutral) is not solidly connected in the transfer switch or transfer equipment Battery/inverter systems where the output is not interconnected Photovoltaic systems where there is no interconnection to the grid or another energy source (off grid system)
Some examples of separately derived systems would include: Transformers, shown in photo 1, where the supply side is isolated from the derived side except by magnetic coupling
The main benefit offered by Isolation Transformers is the input-to-output isolation, where the output circuit can be re-grounded and isolated from input or other ground noise sources. This isolation can also be useful where Ground Potential Rise protection can not be afforded by normal bonding procedures.
I wonder if anyone has converted 3 phase to a home use 120 line like this. I suppose that would even give better quality AC.
Just to be a bit of naysayer/ clarifier the transformer does not "create" electricity as I have stated before. It is just isolating you from the grid from "quick" spikes and drops, any long term spike or drop will effect the other side of the transformer.
The best way for clean AC is to have your own method of developing the AC signal from either using the grid power to DC and then back to AC or from off the grid sources as in solar and wind. The last two are becoming quite popular and should be able to create amazingly clean power (based on the inverter)
Jim, thanks for that clarification. I should have said that the ampacity I ran ends at my receptacle. Beyond that, the product supplies a 12 AWG cord and a 20 amp breaker. The cord is grounded to my receptacle and into the transformer. The company claims of protections from surges, elimination of ground loops--at least between gear in the system-- instantaneous power on demand have led me to believe this is an isolated power supply. At any rate, the results say just that--there is no noise, there is no loss of voltage, no clipping, a vastly improved soundscape--lots of "headroom". I have not altered the unit in any way--it is plug-and-play--just need the outlet. They are expensive-got mine for half cost here on 'Gon from an installer who had an extra--otherwise, would have tried Torus Power, also very costly, but well regarded. I just wanted to report my findings using OCC copper in my DIY AC cables that are supplied by this clean power---outstanding!
mmmm, this thread is informative, jea48, please call me, if you recieved my #, I have done what you have specified, LOL!, everything in my house affects the sound of my sysytem, I have dedicated lines, I need dedicated breaker box with it's own ground for the system!, the ground is where this problem is, there is no other answer?
Yes, I have a dedicated 240 volt line, made from 10 AWG Romex and a 30 amp breaker. 01-01-15: Jafreeman
The 30 amp breaker does nothing more for the available power the ISO xfmr can draw from the main electrical panel than the correct size 20 amp breaker would. The total power that the ISO xfmr can deliver to the connected load is limited by the circuit breaker mounted in the front of the ISO xfmr unit. That breaker is there to protect the unit from a continuous overload or short circuit. The current carrying contacts inside a 30 amp breaker are exactly the same size as a 20 amp breaker. The only difference is the thermal and magnetic trip unit settings. The #10 wire was a good idea but it should be connected to a 2 pole 20 amp breaker.
There is a reason why the manufacture of the ISO xfmr specs a 20 amp circuit, there in a 20 amp breaker. He is following NEC Code which says a 20 amp rated receptacle can only be connected to a 20 amp breaker.
No need to lift the ground--the house ground is not involved,
I hope that does not mean a separate earth ground, ground rod, that is not connected to the main grounding system of the electrical service of your home.
There is a reason why NEC Code requires the neutral conductor of a separately derived power system, (there in the neutral conductor of the secondary winding of an ISO xfmr), to be connected to the main grounding electrode system of the main electrical service. It can be connected to it at any point. (Technically a safety equipment grounding conductor is not part of the grounding electrode system, though it connects to it.)
If you do have a dedicated earth ground that is totally separate from the main grounding system of your home I hope you did not break the equipment grounding conductor/connection that connects to the ISO xfmr unit from the 240V branch circuit that feeds the unit. That could be dangerous.
The Earth does not possess some magical mystical power that sucks nasties from an audio system. .
Jafant, yes, I have had the 240V/120V Substation and the upgraded to the RM Pro for even more power and outlets. Yes, I have a dedicated 240 volt line, made from 10 AWG Romex and a 30 amp breaker. Svan, even though power is not made at the transformer, it makes a lot of power available. Mine receives 240V via 30 amp service = 7200 watts. It steps the voltage down to 120V and preserves 4000 watts available for devices, and, as claimed by the manufacturer, it is all isolated from the house. My amps tell me this--they read at 121 volts constant. The Substation before it that outputted 2400 watts gave them 118 volts constant. No need to lift the ground--the house ground is not involved, again, as claimed--no ground loop issues at all. And this is what I am experiencing during listening. The amps are perfectly quiet and there is no effect on the sound from my house, including an electric range, the furnace, AC, 1/2 horse garage door opener, etc. If you read the claims made by the makers of these transformers, and if you believe them, then all that is left is to try them. I have them, and they have given me stellar results, and I live in a first-ring suburb with above-ground wires on poles that are > 40 years old. The neighbors' appliances don't bother me, either. But what I originally posted was a question about my new AC power cables, and I am answering yes to my own question, and I stand by this.
reading thru this thread there are lots of numbers being tossed around about output of isolation transformers, gauge of wire, and such things.
what appears to be unclear is what sort of amperage is being supplied to these devices from the power grid of the household. an isolation transformer plugged into a 20amp circuit cannot output 4000 watts.....no matter what it's output capability might be. the limitation will always be the amount of amperage input.
stand alone boxes not hard wired into the power grid have limitations as to output. and they typically cannot fully supply the needs of high powered amplifiers.....although there are exceptions. mostly they will limit dynamics of very high powered amplifiers. it's about how much headroom the power grid has to handle musical peaks at those moments when the amplifier demands lots of power right now. line sag comes thru as compression and hardness in the music.
stand alone isolation transformers plugged into a wall outlet can predictably effectively power source gear as they don't have the same huge momentary demands on the amperage.
it can become a choice between lower noise and more dynamic energy when deciding to use a stand alone isolation transformer....or not on power amplifiers.
I am getting at is that, if this is a truly isolating transformer, then there is nothing upstream of it--forget about the house and all the big appliances.
No.... If you have a drag on your power system, like a big appliance you will have the same drag on the other side of the transformer. The electricity is not made at the transformer it just isolates it from the other side. If you want to eliminate the reactive noise coming back up the ground you can lift the ground. I don't recommend doing it long though.
As stated above by another poster, these sorts of things are really used in hospitals, industrial use and labs that need to protect incredibly sensitive electronics. Remember, in your amp there is already a transformer so theoretically your rails are already separated from the electrical mains. And those transformers are typically balanced out so you are getting those same effects of cancellation already.
Mike, the Equ=tech 10wq system looks like a superb product--I am sure it is giving you a very quiet power supply that allows all the inner details to come through. Jea, the unit I am using must be a grounded power system, as it has six grounded receptacles on the back. Looking at these transformers form RGPC and Torus/Bryston, they are very domesticated, made for the living room. There isn't anything easier--just plug it into the wall and plug your gear into it. What I am getting at is that, if this is a truly isolating transformer, then there is nothing upstream of it--forget about the house and all the big appliances, all the switching noise, the voltage sags, the buzzing dimmer switches, waiting until midnight for the best sound, etc. All the power is right there with your gear. Beyond that, there are only your own power cords--your own AC lines. Now, use the best copper available, and you have this nailed. I cannot think of a more pure atomic structure than OCC copper. You are down to an element here. It is free of other metal impurities and oxygen. It has no grain boundaries that cause distortions; the electromotive force alternates back and forth along shared electrons quietly. Your gear operates in an ideal power environment. The music signal is modulated onto this pure power source, so this is what you want from your power. I don't have any EE knowledge beyond what I can read and understand, but sometimes this allows a basic idea to come through as perhaps a profound revelation. I am trying to tell you that two AC power cords are acting like a front-end upgrade here--if I only had words.......In the spirit of reporting great things in this community, I just want to tell all of you, and if just one person also tries this combination, then something has been accomplished. Best wishes for health and a Happy New Year to all.
Richard Gray Power Company makes the "Sub station" isolation transformer in both 102/240V options. It has been in production for more than 10 years. Yes, these devices serve as a resivor for clean power reserve. Additionally, these devices clean your power coming into your dwelling from your power company's line-transformer. Very cool stuff indeed. Lastly, consider a dedicated line for your gear if you live on the "grid". Keep me posted & happy listening! JA
I totally agree with the comment Mikelavigne made regarding power filtration and the use of power cords. I have noticed that in my systems also. A very well made point.
I use the Equi=tech 10WQ wall panel system which includes a 10kva isolation transformer. when I installed this 400 pound panel 4 years ago I did have to re-think the power cords in my system. previously I had Jena Labs Fundamental One power cords with in-line power conditioners. however; once I cleaned up the noise in my power grid with the Equi=tech isolation transformer the Jena Labs actually added noise. so I switched to a more simple approach in a power cord, the Absolute Fidelity power cords for most of my gear. I have 9 of those. they are very simple and quiet. I do use 2 Evolution Acoustics TRPC (triple run power cords) on my 2 dart mono block amplifiers.
some power cords do filter noise, and some do not.
so no, an isolation transformer does not improve a power cord, but it does change the context it is used in. so you must investigate the performance equation for the specific power cord in the new context. I suppose it is possible that the isolation transformer might improve the total picture. but unless you try some alternatives you won't know if the power cord you have always used is holding you back.
All you need is a 240V outlet next to your gear--simple, clean, direct with no worries about phase. 12-29-14: Jafreeman
Jafreeman,
I agree I would feed a 4KVA ISO transformer with 240V as well. Better for isolation of the ISO transformer as well as for balancing the mains of the electrical service panel.
As for phasing if you are by chance referring to my above post it doesn't matter if the primary is fed by 240V or 120V. The outputs of ISO transformers could still end up out of phase with one another.
I have taken the easier but more expensive route by using plug-and-play transformers that are made to sit with your gear, not in the basement under your breaker box. The two best known audiophile brands are Richard Gray and Torus/Bryston. These products have their own AC power cables that simply plug into a wall outlet. I happen to use the Richard Gray Rack Mount Pro. The model below that is their Substation. Their largest is the Powerhouse. The Torus products come in various power outputs, as well. In any case, I would only use a 240V/120V version. All you need is a 240V outlet next to your gear--simple, clean, direct with no worries about phase. The 240V versions deliver more wattage, and this is what you want--a dedicated 120V, 20 amp line will deliver 2400 watts, so you want to equal or exceed that. If you are running two 20 amps lines for two big mono blocks and subwoofers, then you may need an isolation transformer for each side of your system. I also use the RGPC 1200C for my front end. These are all expensive, though, and heavy, as they should be. They do not limit peak demands, they supply them, and, as said, they isolate your system away from ground and grid. Results in my old house have been a broader, more relaxed and articulate low end and sound stage. The new AC OCC cables have taken everything to a new plateau of clarity and presence.
The isolation transformers I use in my system are industrial ones like Topaz. They range from 1 kVA to 2.4 kVA. Another one I use are older Tice Power blocks. The con of these isolation transformers are they are big bulky and not the prettiest to look at.
I've got them from various outlets. Audiogon, Ebay, and Craigslist.
Isolation transformers are used to isolate electronics/ devices from the primary source of power. The benefit of this is that the ground is now independent of everything else so ground loops can go away and short high spikes in electricity do not affect the other side.
In your use, you may be getting some positives from the ground loop issue. Also if you have "dirty" electricity with a high frequency noise in it that is probably being filtered out. A transformer is basically two inductors with a iron loop connecting them to pass the field. At high frequencies inductors act as resistors.
So based on the cable you are using I think you believe in the need for quick clean power to your amp to deal with the high frequency shifts caused by power changes on the power supply in your amp. An isolation transformer will most likely do the opposite, it will not allow the amps power supply to fluctuate quickly.
If you want really clean power that is isolated you would need a bunch of batteries and a really good inverter, much like you see in many high end solar projects.
Lak--yes, the isolation transformer does provide a clean, stable current. My amps read 121 volts input with these large AWG cords, but what I am doing here is plugging my transformer into a 240V wall outlet I installed using 10-2 Romex. The transformer sits under my equipment--it is right there, next to my amps. From the transformer's outlets, I am running these new OCC AC cables directly into my amps' IEC receptacles. What I am seeing here is that there is no grid upstream--just six feet of ultra pure copper as the "last" and only six feet of AC cable--a private power grid. Correct me if I am wrong, but this appears to be a breakthrough realization in providing ultra smooth, quiet power, even though there is a core in the transformer that appears in diagrams to be a material link between the two windings. Even so, this arrangement is giving me something that asks for further consideration. I would like some more input from those with some expertise, Lak included.
IMO: The Isolation transformers should clean the AC line going to your audio outlets giving you a blacker background hence you hear more details in the music. The actual power cord can also inhance the sound. This is what I've been doing for power filtration in my system for the past 18 years or so. I'm not sure if answered your question or if I'm capable of answering it in technical terms.
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