more Line Poles questions

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Comrade Milosh Rektorikov ye asketh:

>>>
Can anyone tell me the use of that top bracket and wire?
Why isn't it on an insulator? Or is it, and you just can't tell from the
pic? -- Mike Rector
<<<

That top wire is the "Static wire." It is up there to catch lightning and run it to ground before it did too much damage. The wire was just steel cable, but it appears to be heavily galvanized.  You can see the same thing up on top of the really big electrical transmission towers, some of which are now carrying around 700,000 volts.   

And there was no need for an insulator, as they wanted to carry directly to ground any current on the Static Arm.  Each pole had a copper wire leading from the Static Arm, stapled down the side of the pole and directly into the earth.   As I recall, the requirement was to form five circles with the ground wire and staple it firmly to the bottom surface of the pole before placing it in the ground.  The Static Wire cable was also mechanically attached (i.e. bolted) at both ends to a heavy ground rod driven deeply into the earth.  All electrical equipment on the railroad was grounded: motors, transformers, signal cases, etc.

Some of this has an analog on the electrical distribution system which brings power to your home.  I cannot speak for the distribution system in your'Hood, but in my 'Hood the top wire (which is bare Copper wire) carries the Primary, 7200 volts. Pay attention to a pole sometime. Immediately below the Primary is the circuit breaker, and coming out of the bottom of the breaker is a wire feeding into the transformer. The tranny has three wires coming out of the side near the bottom: two are energized off the secondary windings of the tranny at 120v (or perhaps a bit closer to 130v,) and the third is the Neurtral. On the pole, but below the tranny, is a steel cable serving as the Neutral in the system, and as the "return" side, which is ultimately connected back to the main transformer at the generating station. The various stuff constituting the bottom collection of wires on your neighborhood pole line (and usually attached directly to the pole, without the use of a cross arm) is the co
 mmunications (sometimes called "commie") stuff: telephone and fiberoptic cable.

Last week I had a wonderful walk around the neighborhood with my 12 year old Grandson. We examined and discussed poles and transformers, and how electrical power is delivered to the home. We also discussed expansion cracks in sidewalks, and why one should always look up before parking his automobile, avoiding dangerously overhanging tree limbs, if possible. We also discussed the shape of the branchlets on the Arbor Vitae plant, and how a proper gentleman should walk, not ape-like, but in a more refined manner, and we finished with a little brush-up on etiquette at the dinner table. All of which things no older man ever discussed with me as I was growing up. Which is why I so much enjoy being a Grandfather! Then we came home and did some Algebra homework.

Stay away from the hot stuff, Mr. Rector... it only takes 1/16th of an amp to stop the human heart !

-- abram burnett
Financial Secretary of the Turnip Cartel