seriously dont worry about answering this if its too much, i copied all of this to a word document and tried to sort out mostly scotts and pauls replies, but if you dont answer anything else, please tell me how the electricians in the UK refer to 1/2" EMT or 3/4" flex, for instance if i asked them for
a stick of 1/2" EMT would they say: 'eres yer 13-millimeter EMT matey [Linked Image] also think i've heard 1/2" rigid referred to as 16 metric maybe, not 13?

You said this: Capacitive Coupling effect is present whenever there's current flowing, or available to flow on circuits, and there's any difference in Potential - either externally or internally to the conductors.

Questions: Do you have examples of the difference in potential "externally"? Vs "internally"?

You said this: Let's say you have a length of feeder with a measured capacitance between hot & neutral of 0.5uF (microfarads). Assuming a U.S. supply of 120V at 60Hz, the reactance will be: X = 1 / (2 x 3.142 x 60 x 0.0000005) = 5300 ohms approx. That reactance is directly across the supply, so (ignoring the series resistance of the wiring, which is negligible by comparison) there will be a capacitive current of: I=120V / 5300 ohms = 0.0226 A.

Questions: What do you mean “that reactance is directly across the supply”? Potential difference? Electric field? Does the “line charging” ‘couple’ hot to hot, hot to neutral, hot to ground, and neutral to ground? Does capacitive coupling result in reactance and current flow only between those conductors coupled to each other? In other words, lines A and B are coupled, but lines B and C are not close enough to couple, so how does the capacitive coupling current flow in line A or line B relate to line C? If line B touches line C does it discharge? It seems like we’re talking about 2 effects, capacitive coupling results in current flow, and capacitive coupling results in reactance that inhibits current flow.

You said this: 22mA is hardly going to be a problem compared to the probable load on that feeder, and because it is reactive current it isn't actually consuming any power anyway.
Also you said: Although reactance and resistance are both measured in ohms, we can't just add them together because the voltages across them are not in phase.

Questions: What is the difference? Is reactive current like a different sine wave, different phase, or beyond my comprehension at this point?

Questions: In the example there is 2.66 megohms capacitive reactance in the light switch legs tested with a digital meter. Why is there 10 megohms of resistance in the meter? Why can you use 120v in the I=ExR formula since we started with an open circuit without voltage on it?

You said this: In some cases you're not aiming for reactance as high or as low as possible, but for a certain optimum value. The capacitor in a split-phase motor is a good example.

Question: Is there a short explanation for this, or is that another thread?
thanks -C-