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Balanced vs standard power

Searching for an Isolation Transformer 10 or 15kva. I have the budget for Equitech but I'm sold only on the benefits of isolation and not "yet" on the benefits of balanced power unless one is recording live musicians. My rationale is that most if not all audio components are not designed with balanced power so they may be optimal performers with standard power and lesser performers with balanced power. Until someone does a side by side comparing isolated balanced to isolated standard power we may never know.

I have read the various threads regarding isolation transformers from Equitech 10wq, MGE Topaz etc, and the Euqitech stereophile review. For larger non-balanced options there is Ultra K 600 with K factor correction and triple shielding from the Controlled Power Company. They range from 5 to 25 kva.

I think supersizing Isolation transformers for audio is not well recognized yet because no one has done the necessary review/ comparisons to determine the performance curve of Isolation Transformer size to Audio Performance. Although Isoclean advocates the use of two of their Isolation Transformers for each piece of equipment. Maybe they're trying to tell us something or just sell more transformers. 10 KVA is "plenty" for my system according to Martin at Equitech, but "plenty" is not quantified enough to convince me, so I 'm leaning toward the 15kva on the Ultra K 600 from Controlled Power about $4000 vs Equitech 15 kVA at upwards of $14000.
natan6355
jea48
2,944 posts
 
11-07-11: Ngjockey
Sorry, misled again.

UL101 and IEC 60335/60990 are more consistent than I was told. IEC is specific about class and such but generally leakage limited from 0.5mA. Difference is that IEC specifies true RMS reading.

Still, that's per appliance.

Ngjockey,

Big difference between 5ma and 0.5ma!
So much for my memory concerning UL standards.
IEC 60335-1 Standards.
.
ngjockey
1,042 posts
 
Somewhere between a decimal place and half a heart attack.
jea48
2,944 posts
 
Somewhere between a decimal place and half a heart attack.
11-09-11: Ngjockey

LOL, though actually 5ma of AC current passing through the heart will not kill or cause heart damage. At least NEC code doesn't think so.

5ma is the maximum amount of leakage current,("consisting of possible resistive and capacitive leakage currents"), for the audible alarm to sound for a Line Isolation Monitor for an AC Power Isolation System found in Health Care facilities in; OR, Cath Labs, and ER rooms where electrical monitoring equipment and such may be connected to a patient. (Also required ma meter. Green light for normal, red light for alarm condition.)
2011 NEC 517.160 (B) (1) (2) (3)
Notice I said alarm, the power is not interrupted.
Though I would assume the doctor or techs in the room would disconnect the medical equipment from the patient in a timely manner or at least monitor the milliamp meter.... Don't know the answer to that one...

Also per NEC a GFCI is supposed to trip open around 5ma of current when detected between the hot to earth ground/earth grounded object. (GFCI senses more than just the hot to earth ground for its operation).

The problem with UL they only test new appliances as far as I know of. New at normal operating temperatures.
Not necessary the case in the real world.
As you know heat will degrade the insulting resistive covering the conductors of motors and transformer windings. Over heating, excessive overheating, caused from ambient temperatures or over working of the appliance can cause a break down of the insulation and result in more leakage or worse case a short.

http://hypertextbook.com/facts/2000/JackHsu.shtml

4krow
79 posts
 
Jea48 THANK YOU! GOOD LORD, why don't we just hook a dedicated line from a substation. There is no doubt that this 15KVA is an overkill idea. I used to work with dc current 60-1,200 amps. requiring less than 1/4 voltage drop. For that kind of specification, we sometimes used cables as big as you'r wrist!(750kcml). I don't doubt that they engineered these battery circuits for very specific purposes. So when I see consumers buying bigger is better thinking, I know that there is an uneducated/greedy salesman lurking in the shadows. Yes, there is a great need for clean power, and balanced power is very effective for cancelation of noise. Yes, there is a need for adequate reserve, but don't you think that a DECENT piece of equipment(such as Levinson) considers that in their design? No doubt you should have low impedance, and the best(read tight) connections required. Yes can analyze this to death, but in the end, your ears are to be the judge and not some hype/misinformation.
natan6355 OP
14 posts
 
Thanks for all the advice.
I am still leaning toward 15 kva Isol trans due to the size of my system. I have a dedicated 100 amp service from the electric company transformer feeding a dedicated 9 circuit/ 80 amp isoclean breaker panel. This service shares the same power meter with 2 other 100 amp services feeding my 2 household breaker panels.

I have 3 systems fed by the isoclean breaker panel which includes hometheater with projector, processor, large multichannel amp, 3 powered subs, multiple sources, housewide music distribution with 1 large multichannel amp and 1 large stereo amp and multiple sources, and finally 2 channel system with 1 amp, 4 powered subs, digital, vinyl, reel to reel sources, main preamp and phono preamp. Also several large plasma screens.

In the future I anticipate more computer based sources and processors, more amplifiers and more screens and possibly a 4th system.

during the summer and fall I usually have 2 systems working simultaneously. Winter and spring usually 1 system at a time. On rare occasions all 3 are going.

All electric services come in through my garage which is the location of my isoclean breaker panel. The 450lb ultra k will be installed in the garage immediately adjacent to the panel. This location is completely isolated physically from all systems.
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