Audiolabyrinth,
Sure, no problem.
Jim
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?
Showing 7 responses by jea48
All you need is a 240V outlet next to your gear--simple, clean, direct with no worries about phase.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. Jim |
Yes, I have a dedicated 240 volt line, made from 10 AWG Romex and a 30 amp breaker.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. 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. . |
Just to be a bit of naysayer/ clarifier the transformer does not "create" electricity as I have stated before. Scvan, Other than you, who has made such a statement? ~~~ Separately Derived System. NEC 2011 Article 100 Definitions Separately Derived System.
>>>>>>>>>>>>>>> http://www.jade1.com/jadecc/courses/UNIVERSAL/NEC05.php?imDif=10 http://www.jade1.com/jadecc/courses/UNIVERSAL/NEC05.php?imDif=10 >>>>>>>>>>>>>> http://ecmweb.com/nec/grounding-and-bonding-separately-derived-ac-systems An Isolation transformers is a Separately Derived System. >>>>>>>>>>>>>>>>
Some examples of separately derived systems would include:http://iaeimagazine.org/magazine/2009/11/16/separately-derived-systems/ http://iaeimagazine.org/magazine/2009/11/16/separately-derived-systems/ ********************* http://www.erico.com/public/library/fep/technotes/tncr016.pdf . |
Jea, Again,
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? . |
Jafreeman, 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. . |
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. 3.1.6 Separately Derived Systems, by Henry Ott. >>>>>>>>>>> What a shielded isolation transformer does. >>>>>>>> EXACTPOWER, PDF 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. >>>>>>>>>>
What are you plugging the 1200 into? The RM PRO unit? >>>>>>>>> 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. . |