ok so let me give you the complete story. I didn't buy the EMI filter, I borrowed it to make some tests because I was skeptical about this unit so I built a small test box by wiring a voltmeter, ammeter and its shunt as indicated in the previous links, a regular home wall switch and 2 plugs and I connected the plugs as in my drawing (#2) I had the AC supply feeding the switch and then the shunt and then a small power supply I made to provide 12 volts to voltmeter and ammeter.
From the above configuration I plugged the EMI filter in plug B and a motor in plug A, turned on the switch, motor came on, ammeter showed 6A, turned on EMI filter and nothing changed, still reading 6A. (double checked with my clamp-on meeter to confirm) and made sure I have 120V in plug B.
I then connected the wires like in #1, did the same test and when I turned on EMI filter the ammeter dropped to 3A.
Surprised overwhelmed and confused I decided to make another test.
I plugged-in the EMI filter in the bottom outlet of my garage plug and the motor on the top outlet (both on same plug) along with my clamp-on inductive coil and turning EMI filter on in this configuration made no change in Amp reading which was at 6A.
At that point I figured my garage plug was separated in 2 breakers so I plugged in a power bar on that plug and did the same test this time plugging the EMI filter and the motor on the power bar and it turned out the EMI filter reduced from 6A to 3A when turned on.
I then gave back the EMI filter to its owner and I was still confused... I opened my garage plug to find both outlets are on the same breaker.
I have been getting headaches and migraines since and I am glad to see Sherlock Holmes in my path.
I will definitely redo my tests and I will either film or take pictures because its not making sens and I believe to still have all my head, I am only 50!
I now understand better the power factor issue but why the difference between #1 and #2 as well as on the plug and on the power bar?
Maybe the EMI filter is defective with a loose contact and only works sometimes?
If not, it is still a mystery.
Does my story help clarifying anything?
Mike