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Please enlighten us Argile, as to how you define Ohm's law in AC terms and exactly who taught you this.

This board, Mr. Ohm, Mr. Volta and Mr. Ampere all disagree with you.

Gee, talk about maintaining a professional conversation...i'm sure if anyone came to this board who was unfamiliar with electricity, they would say that i was the correct one, because you all sound like a bunch of 9 year olds. Grow up.
Secondly, as i stated in my response to the guy who first responded to me, IT'S NOT ABOUT WHOSE TEACHER IS RIGHT OR WRONG...that wasnt even my point! Really, it wasnt even a supporting point! Respond to my points if you're going to respond at all, because you're dodging my main point (the part that i KNOW is correct).

Ohms law applies whether your units are DC, ACpeak, or ACrms.

A transformer with a secondary rated at (for example) 10 VAC 1 amp has a nominal output of 10 volts RMS and is rated for 1 amp of continuous output. That doesn't mean it will magically drive one amp into any and every load, but rather it is rated to not catch on fire or sustain insulation damage while delivering up to 1 amp of continuous current, and its output voltage should be reasonably close to 10 VAC while delivering up to 1 amp to the load. That's all. Similarly your car battery won't drive 500 "cold cranking amps" through you if you touch its terminals. If you touch the output of a 10v transformer (or battery) and measure the current through your body, you would likely measure far less than 5mA and not feel a thing. If you think a transformer will always run it's rated current through your body, then wouldn't it follow that you absolutely cannot be killed by any transformer rated at under 5 mA? That is plainly false.

Ok, I just did a little experiment...I put myself in series with a current meter connected to a "12 VAC 1.3A" power supply. The output of the 12VAC supply measures 14.7 VAC(rms), and I know this particular supply will deliver over 8 amps for several seconds when shorted. Holding one lead of the DMM between the thumb and index finger of one hand while holding the power source output with the other hand gives a current reading of .28 mA (0.00028 amps), for a calculated body resistance (at this voltage) of 52500 ohms.

Experiment #2. 98 VDC, measuring current through me hand-to-hand as before --- 0.47mA for a calculated body resistance of about 21000 ohms. This is a span powered T1 line I'm touching in this test. I wouldn't recomend doing this, but when you work in the telecom field you touch these by accident all the time (because you know its no biggie, else one would be more careful) and get used to it. I can't even feel it with my fingertips (should try the tongue method!).

Experiment #3 -a 200VDC communications circuit. No way, it bites!

I'm ready to jump into that bath with the laptop now...

I didnt say a transformer of that sort. Clearly that sort is not suited to power transmission. Though, your voltage isnt enough to do any human damage with any transformer...but if you had 10kv and stepped it down to 10mv, the resulting amperage would be very very high (the opposite of power transmission)

Such impedance there, electech.....


Argile, perhaps you should
check out this link ....

Nice Graph: Check
Response to my point about power transmission or amperage being what kills you: _____
It doesnt even have anything about the little sub-argument which i'm trying to avoid about DC math being used in AC systems

Argile,
How can 0.001 volts cause any real amount of amperage to flow through a human? The current is limited by the impedance of the path. High impedance equals low current. Ohms law does apply to AC and is used every day. The only real difference is that you use impedance in place of resistance.
Don

[This message has been edited by resqcapt19 (edited 11-20-2002).]

If that is true, then how does power transmission work? How do transformers that step-up current and step down current work? (well ig uess that last one isnt really a rhetorical question, but you get the idea). Both of these are used every day also.

Argile,
What are you asking about in your last post????????????
Don

See, you cant even respond to my points because you dont even know what power tranmission is about or who it works...like i said before, it's gotta be the same way throughout the entire board (and now i see you, along with sparky, dont understand it)