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Joined: Aug 2001
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pauluk Offline OP
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Red-yellow-blue are the standard phase colors used in the U.K., but seen here on 12kV lines in CA:

[Linked Image]

Thanks to Bjarney for the photo.

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Unruly far-west colony has adopted a centuries-old, hallowed and reverential act of Elizabethan tribal symbolism.

Noted channelist/vaguely clairvoyant television spiritualist Clotille Xirgita Onderdonk [illegitimate grandniece of Mama Cass] predicts taxation of practice to be godsend for state automobile registration-fee boondoggle.

Production camps for Ricki Lake, Jerry Springer and Barbara Walters are reported to be in bloodthirsty bidding war for broadcast and set-catering rights.





[This message has been edited by Bjarney (edited 12-20-2003).]

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Paul, I originally learned RED-YELLOW-BLUE from an old man from Australia. He gave me his books from the Royal Melbourne Technical College...This was my "formal" education.
Watch out for yellow on a secondary line here in CA.
They use yellow stripes on their grounded (noodle) conductors.
(They're able to make their own rules) [Linked Image]

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Bjarney, although Mama Cass had an excellent voice, I didn't know she had any legitimate relatives that could produce illegitimate kin.

I'm going to read my post a few times to see if I understand what I just said. [Linked Image] [Linked Image]

Roger

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Sorry folks—I don’t have an answer for the color sequence. There were two new ‘riser poles’ close together, and they were the same. At first I guessed the phase sequence must be viewed from the fused-cutout side, but nothing explains Y-B-R or R-B-Y…

Roger, I was just trying to give the story a ‘celebrity spin,’ but I’m in the wrong end of the state to make that work.

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Now there's a turn-up for the books!. [Linked Image]
Mind you Bjarney, as long as the colours aren't the same as a Neutral or an Ground conductor and the colours are the same throughout the system, what difference does it make what colour the wires are marked as?.
Just a small question, what sort of material are them markers made out of?.
We use small coloured plastic discs here, that are screwed into the cross-arms below the insulators, to identify phase sequence, but this is only done at Spur lines, Service drops, Transformer poles and anywhere else where there are fuses or switches.
Phase conductors of cables leaving poles are identified with Heat-shrink tubing. [Linked Image]

[This message has been edited by Trumpy (edited 12-27-2003).]

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[Linked Image]

Yellow for A phase, Red for B phase and Blue for C phase is a common color coding for medium voltage circuits around here. This is a picture of a 15KV switch viewed from the back. (A phase is on the right, sorry for the bad quality) I have no explanation for the sequence on the pole in the above picture.

- Nick

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pauluk Offline OP
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Same colors, different phase order. The sequence in Britain is A=red, B=yellow, C=blue.

Yellow has been in use only since the mid 1960s. Prior to that, phase B was white.

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Oddly enough Paul,
While in most installations here, we are required to use White as Phase B, where cables are used.
Overhead lines are a different story, we are told to use Red, Yellow and Blue.
Why this is, is just beyond me, you'd think you would make all the colours the same.
Even in the latest Electrical Supply Regulations, it still mentions RYB as the colour coding for 400V-220kV lines.
Go figure. [Linked Image]

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Seen the same Color Coding on a few newer Primary Risers - such as the one in this Image, in various parts of Southern California - and Northern California.

ØA = Yellow,
ØB = Red,
ØC = Blue.

ØA would be normally Black, my guess is the Yellow gives it a tagged color which helps eliminate any second guessing as to the Phase Arrangements (i.e. Black Tape on Black Insulation = ????).

Looks like the Phase arrangement on this pole ended up as A, N, C, B (if the 2nd from the left is a Grounded Conductor, that's the "N" - looks like the 4 wire Primary Feeders around here, however the Grounded Conductor normally lands on a White Insulator at each pole).
The offsetting of B and C would be from "swapping positions" at certain intervals, for tuning the lines per Capacitive Reactance.
See it done on all systems at certain intervals. Not sure what the proper term for it is (or the Linemans' slang term either), but I do know it's to keep Reactance in check.

Anyhow, IMO, that would explain why the "Backwards Rotation" of A-C-B is seen here.
I'm sure the other end (at the Transformer it's feeding via Underground duct) is "Phase Proper" - having the Yellow Tagged Feeder landing on H1, the Red Tagged Feeder landing on H2, and the Blue Tagged Feeder landing on H3.

My 2¢

Scott35

p.s. have seen our local DWP's Line Crews tag many Primary Feeders with wraps of white tape, numbered per Phase line as:

1 wrap = ØA,
2 wraps = ØB,
3 wraps = ØC

Will get some pic's of these for posting.

So far, the white tape has not caused any problems or fires, and the Electrons are not afraid to flow past these points when seeing the white tape.

[Linked Image]

Just a bit of humor!

S.E.T.


Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!

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