Basic speaker cable question

Status
Not open for further replies.
Jump to Latest
#41
PRR said:
You mean, to a dirt-rod?

I have. The bulb is dim.

This with a nominal 120V 0.5A (60W) lamp and 7 feet of rod under my septic field; and the power company dirt-rod (2 8') on the far side of the field.

My summary data suggests around 120 Ohms from a full size dirt-rod to another rod on the same land, implying 60 Ohms from one rod to an imaginary "true earth".

My 60W lamp is nominally 120V/0.5A= 240 Ohms, so 60-120 Ohms in series makes it dim. (And a dim bulb is a lower resistance, so I was getting like half of line voltage.)

This incidentally means I can NOT blow a breaker with "earth current" literally through dirt. Three 60 Ohm rods is 20 Ohms, marginally under the NEC goal of 25 Ohms, but 120V/20r is only 5 Amps, and my smallest breakers are 15A.

Things CAN be different on the damp salty coast of Florida.
Click to expand...

It all depends on the conductivity of the soil. It's a test I did many times (before the differential switches were invented) and it always worked. Surely this protector (great invention) will be activated, so I will disconnect it and I will do it again. Here the lamp lights up in all its luminous intensity.
Here we have 220 volts / 50 Hz. It is a very humid climate and also live near the Rio de la Plata. And there is a very old power plant (which was fueled by coal, then gas) in Puerto Nuevo, Buenos Aires. They took the neutral and connected it to a huge copper plate submerged in the muddy bottom of the River. I have a javelin connected to the entire neutral installation of the house, so I'll use it to repeat the experiment.
 
#43
For what it's worth, there is a type of residential power distribution system called SWER, which stands for Single Wire Earth Return. For 20 years lived in an old neighborhood with this system. A single 2000 volt wire fed one end of the pole transformer(s) primary and the other end went to a ground rod. So the return path back to the power station was through the ground/dirt/mud/water for several miles. The regulation isn't good and our line voltage would be anywhere from 102 to 125V. I couldn't believe such an archaic system is still in use in metropolitan New Jersey in 2019. It was probably installed by Westinghouse himself and hasn't been upgraded since. I am an EE who went to college in the 70's and this wasn't covered in any of our power courses. I learned about it by living with it.
 
#44
> such an archaic system is still in use in metropolitan New Jersey in 2019

Where??

We had some funky junk in ex-NJ-farmland grown into suburbs, former "farmers' cooperative" wiring, but not like that.

(PM me if you rather.)
 
#45
The best cable is the one made from unobtanium material. You can't make it. You can't listen to it. It works best when You really need moments of silence. I believe I have somewhere lying around old headphones with rare metal ?? magnets. There are many companies who want Your money. Trust me !!
 
Status
Not open for further replies.
Top Bottom