All,
Today John has sent along these short paragraphs to explain how our unit works without giving away all of the Secret Sauce. I know from first hand experience that most likely this will raise even more questions (or at least has the potential to)... but we hope this will suffice.
John is a consummate New Englander. He's to-the-point and "lets get on with it" kind of guy. He is not everyone's cup of tea - but I love him dearly.
Here are his few words on the subject (unedited - even though I was tempted in a few places ::)
+++++++++++++++++++++++++++++++++++++
I understand that one of your customers tried using an off-the-shelf AC Line
Voltage Polarity tester on the the output of an Equicore and was confused by
the results. He or she should be: it's the wrong tool for assessing the
Equicore's properties.
Conceptually, Equicore is a simple unbalanced-to-balanced transformer, as
described in numerous on-line references. (Google and its brethren are your
friends.) The 120 (or 240)V AC line voltage is impressed on the primary, and
the output is wired to deliver a center-tapped 120 (or 240)V output. This
offers significant audible benefit in cleaning up common-mode noise coming from
the AC line, at least to my aging ears. For safety, the secondary center tap is connected to the green ground from the AC line. There is no magic here.
Your typical AC Line Voltage Polarity tester measures the voltage from green
ground, the long prong on the AC plug, to each of the other 2 prongs. One of them
is called "hot" and the other "neutral". The
"hot" one should exhibit a 120V (or 240V) difference from green
ground. The "neutral" wire should be pretty much at ground and will
typically be no more than a few 10's of millivolts from ground. The Polarity
tester "lights some lights" to indicate these voltages in sort of a
"go/no-go" fashion. In some instances, the hot and neutral are
inadvertently swapped or otherwise incorrectly connected, which can cause
problems for some equipment. Hence the need for such testers.
The reason this is the wrong tool is that both hot and neutral are the same
voltage (~60V) away from ground for Equicore! That's the way it's supposed to
work in order to derive its many benefits. Again, I don't know why someone
chose to try to assess the performance with such a device, as its indicators
would not be as expected.
It's important to note the a safety ground is assured by connecting the
center tap of the transformer secondary to green ground. Any equipment whose
chassis is ordinarily grounded to the AC line green ground will still have this
connection.
HTH.
JL
+++++++++++++++++++++++++++++++++++++
So - there you have it. Ground IS IN PLACE... but in pure-speak it might be "masked" to some measurement techniques. John makes note of that here
=====
For safety, the secondary center tap is connected to the green ground from the AC line. There is no magic here.
=====
We have not had any issues with respect to this and to today we have still had one only return (from The Netherlands).
None of this is simple or easy (at least I don't think it is) and I applaud vigorously the work of @ozzy for his analysis - given the tools he had. His offending sub(s) are not plugged into any of our outlets but given the system is by definition "A SYSTEM" he was looking at all potential causes. We did get caught in that rip-tide a bit.
I'm here to help - although very little voice recovering still from whatever virus has invaded my chubby body.
Thanks once again...
Best wishes -
Mark
