How to read utility pole markings
What do numbers on electric poles mean?
Some of the numbers indicate the location of the pole. You could call the utility company to report a problem and give them the pole number if you don’t know the address. Other tags can indicate if the pole is safe or unsafe to climb or can indicate when the pole was treated to resist rot or insect infestation.
Are utility poles numbered?
One utility owns the pole, but multiple utilities use it — and each has its own way of numbering it. “For example, if Pepco attaches a power line to an existing Verizon pole, Pepco will add Pepco’s unique number to the Verizon-owned pole,” said Pepco’s Christina Harper.
Why are there numbers on light poles?
By numbering your pole lights, that takes away all the guessing. If your pole lights are numbered, your preferred electrical contractor should be including on their invoice the pole light numbers that were fixed so that you have it for your records (and they have it in their records as well).
How do you identify power poles?
It is easy to tell power lines apart from these types of lines – power lines are always higher up on the pole, they always have insulators, and they do not touch other lines. Cable and telephone lines are located further down the pole and are directly attached to power poles without insulators.
What does a red tag on a power pole mean?
Poles with less advanced decay conditions are classified as “non-priority.” Poles are originally red tagged during inspection when the remaining strength of the pole is compared to the original strength of the pole.
What wires are on a utility pole?
What Are Each of the Wires on Utility Power Poles?
- Static Wire. The utmost top line of the utility pole is the static wire. …
- Transmission Lines. Below the static line are three power lines called transmission lines. …
- Grounding Conductor. …
- Primary and Secondary Line. …
- Neutral Space. …
- Communications Lines. …
- Grounding Rod.
What is a pole number?
The number of pole pairs (p) or number of poles for an asynchronous motor determines the motor’s synchronous speed: Two-pole and four-pole asynchronous motors are typically used for centrifugal pumps. The rotational speed of these motors can be varied using frequency inverters.
What does ous mean on a utility pole?
Osmose Utility Services
But rather than being graffiti, a gang message or a misspelled reference to The Ohio State University, the marks are actually part of a Penelec maintenance project. And “OUS” is the initials for the Penelec contractor completing the work — Osmose Utility Services.
How old is my utility pole?
Most poles now have a metal serial number tag. This number is used to inventory the pole and keep track of its inspection, treatment and age. The first marking is the date that the pole was treated.
What are pole pairs?
The pole represents the number of permanent magnet poles for the rotating rotor, and a motor with one pair of N pole/S poles is called a two-pole motor. The number of poles can be 2, 4, 6, 8,…, etc.
What is the diameter of a utility pole?
There is also a minimum top circumference that is the same for all species and lengths. For example, a class 1 pole has a minimum top circumference of 27 inches. If it is 25 feet long and cedar (most utility poles are cedar), the circumference measured 6 feet from the bottom must be at least 43.5 inches.
What is a 2 pole 3 phase motor?
On a three-phase motor the pole pattern has to be repeated for each phase. Therefore a 2=pole, 3-phase motor will have six poles.
How do you check a motor pole?
What is number of pole in motor?
The pole count of a motor is the number of permanent magnetic poles, north and south, on the rotor. There is always the same number of north and south poles on the rotor. For example, in a 12 pole motor, there are 6 north poles and 6 south poles. This motor would also be considered a 6 pole-pair motor.
How do you find the number of pole pairs?
The formula is n = 60 x f /p where n = synchronous speed; f = supply frequency & p = pairs of poles per phase.
What is pole in motor winding?
The pole represents the number of permanent magnet poles for the rotating rotor, and a motor with one pair of N pole/S poles is called a two-pole motor.
What is RPM in electric motor?
What Is the RPM of a Motor? RPM is a measurement used to describe a motor’s speed. It stands for revolutions per minute and describes the rate at which the rotor is revolving, which is the number of times the rotor shaft completes a full rotation each minute.
What is pole frequency?
A pole frequency corresponds to a corner frequency at which the slope of the magnitude curve decreases by 20 dB/decade, and a zero corresponds to a corner frequency at which the slope increases by 20 dB/decade.
What is a 4 pole 3 phase motor?
With a 4-pole machine, the rotor will move from 1 pole pair to the next in 1 AC supply cycle, so will do half a rev in one supply cycle – the synchronous speed is therefore 50/2 revs per second, or 1500 rpm. A 4-pole induction motor will have a nominal speed of 1450 rpm or thereabouts.
What is 2 pole and 4 pole motor?
What is the difference between 2-Pole Motor and 4-Pole Motor? 2 pole motor has two poles (or a single pair of magnetic poles) while 4 pole motors have four magnetic poles in alternating order. 2 pole motors have twice the speed of a 4 pole motor.