What are specs? Specs are the blueprints for building powerlines. They list every piece of equipment you need and where to install it.

Every co-op you work for will have a different and sometimes stupid way of framing poles. The good thing is that the basics pretty much stay the same while only details change.

Phase Letter

The phase letter in your spec code will always mean the same thing. These letters simply let you know how many wires you will have to support with your pole.

A Phase

If a spec starts with A or VA (e.g. A2.2), that means it’s a single-phase pole. To dumb it down more, A = 1 hot line + 1 neutral.

B Phase

If a spec starts with B or VB (e.g. VB1), that means it’s a double-phase pole. To dumb it down more, B = 2 hot lines + 1 neutral.

C Phase

If a spec starts with C or VC (e.g. C5.1), that means it’s a triple-phase pole. To dumb it down more, C = 3 hot lines + 1 neutral.

Want the D?

D Phase is known as double-circuit primary. It's the red-headed step-child of distribution powerlines. 6 hot lines and a neutral.

ID Number

The number immediately following your phase letter determines the main design of your pole. This number means the same thing across all spec books. 

1 = in-line pole. The lines pass over the pole.

2 = in-line pole. The lines pass over the pole with double equipment.

3 = angled in-line pole. The lines do not stop at this pole, but they have an obtuse angle.

4 = angled double dead-end. The line stops at one angle and starts at another. Acute and obtuse angles.

5 = dead-end. The line stops here. These are typically your “destination” poles.

6 = in-line double dead-end. The line dead-ends on one side of the pole and starts on the other.

* You may notice a 4 is just two 5s at an angle or that a 6 is two 5s back-to-back. I’ve seen a 90 degree corner labeled with a 4 and I’ve seen it with two 5s as well. They’re basically the same thing. It depends on what your engineer decided to call it that particular day. 

Specific Specification Numbers

After the ID number, there will be a dash or a decimal, then more numbers. These numbers will indicate your co-op’s specific design for that pole.

Here are some examples of different spec book’s variations of the same type of pole: 

This is a VC2.21 from Central Rural Electric Cooperative’s (Oklahoma) spec book
This is a C2-2 from the Tennessee DOT Utility Specification Book

As you can see, they’re both C phase and they’re both doubled up on equipment. One chose to use a dash while the other chose a decimal. These are the same spec minus a few details like the size of the cross arm.

Hopefully, this drives my point that all specs are mostly the same and if you learn the basics, you can take that knowledge to any powerline company/co-op.

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