How does 50hz motor differ from 60hz motor?

"petrus bitbyter" wrote ...

Of course, same here (and likely most places). But I thought we were discussing what was actually WIRED INTO THE HOUSE. Although it is not necessarily common deep within large residential areas to see all three phases going down the street past your home. You can save money by not distributing what you will likely never need in the forseeable future.

Reminds me of the story of the power utility guy giving his friend directions to his house. Went something like... "Follow the 38K feeder to the fourth stepdown, turn left and follow the 19K branch to the second crossover, turn right, two blocks past the isolation switch, and I live at the third transformer."

Our entire residential city grid isn't even wired for 3phase here in TORONTO!! (not the GTA, just surrounding areas).

The transformers on the street are 1phase 220V, there is not 3 phase power running on the poles, that would have a huge effect on balancing the phases.

Comes from the step down from the transformer station as 1ph.

In Canada, we step down using a three phase isolation transformer usually stepping down from 600V

Three Phase you get a potential of 208Volts between two phases Three Phase you get a potential of 110Volts between Ground & Hot of any phase Single Phase you get a potential of 220Volts between Phase A and Phase B Single Phase you get a potential of 120Volts between Ground & Hot of any phase

This is assuming a step down transformer is used for regular low voltage AC requirements.

What I meant to say about European voltage in *ALMOST* every respect is that there is a

220V+ potential between Hot and Ground, I thought that was pretty clear. Valencia Spain is 230V, I was there recently working with a design team of a professional amplifier, then in the UK, 240V was used as the primaries and the amp had problems, They were using a 115 O 115V transformer, it worked on 'any voltage'. Meaning, we could wire it here for 120V, but, we were over voltage because the primaries were wired for 115V. Same with the UK, across the two 115V primaries, instead of feeding 230V, they were feeding it 240V, blowing up components in the amp.

First of all, are you aware that there is "Florida Power", and "Florida Power & Light"? Two different companies. BTW, "Florida Power" recently changed their name to "Progress Energy"

The house had a pad mounted transformer like you see for a small strip mall. They had 120/208 three phase fed to two 200 amp panels that I know of. The owner died a few years ago, and the property ws on the market so I can't call and get any details. The one thing to keep in mind is there is a different rate structure for three phase power. I ran into a "Progress Energy" tech the other day and saw he had a pile of current transformers in his truck I talked with him a couple minutes, then he told me he had just replaced the C-ts at the Microdyne plant in Ocala (I worked there till they started closing the plant) because the meters were not showing any power use for the security lighting, and several other small loads.

There was a small house next to CH55's (WACX, Orlando) original TV tower in Lisbon, Florida that had three phase power as well. The transmitter building and the house were on the same meter. "Florida Power" contacted the station to tell them they were going to pull out the transformers because the transmitter was no longer in service, but changed their minds when they were informed there were several repeaters on the site that needed air conditioned, and it used three phase. It was cheaper to leave three phase service than replace all the three phase equipment in the two buildings.

--
Merry Christmas!

Take care, and God bless.
Michael A. Terrell
Central Florida

(not the

running on the

A lot of subdivisions only have a single phase per street service because there is no zoning for commercial service.

--
Merry Christmas!

Take care, and God bless.
Michael A. Terrell
Central Florida

Some things are really different here. I have an old radio from the fifties that has a voltage carousel with eight different mains voltages ranging from

110V to 240V. That's where we came from. The mains were standardized to 220V over the years but there are still local exceptions. During the last few years the voltage was slowly raised to 230V and it is said to become 240V over time.

Where I live (in the Netherlands) power production and distribution is done in a three phase system. For all I know there are no air lines left except for >100kV. So a power utility guy will get lost. Local transformers step down from 10kV or 25kV to 400/230V. They have to service tens to hundreds of houses. The power cable ends up in a house in a sealed black box. There one phase is selected and connected to the kWh meter via a 25A fuse. (It may be somewhat over 25A these days.) If you are a power user you get three phases. For instance, one of our neighbours has an electric cooking-range and has three phases. Commonly called "powercurrent". So if someone needs more then the usual (~5kW) power for whatever reason they only have to rearange some connections and replace the kWh meter for a three phase type. This way they can do almost all control and maintenance without digging. Digging is by far the most expensive part of the laying of the power grid so they want to do it only once.

petrus

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[snip]

I had three-phase power in the first house I bought in Scottsdale, Arizona (in 1964).

It was in an area bounded by 68th St. on the west, Scottsdale Rd.on the east, Oak St. on the south, and Thomas Rd. on the north.

Had a nice three-phase Goettl air conditioner that purred like a kitten ;-)

...Jim Thompson

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|  James E.Thompson, P.E.                           |    mens     |
|  Analog Innovations, Inc.                         |     et      |
|  Analog/Mixed-Signal ASIC's and Discrete Systems  |    manus    |
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|  E-mail Address at Website     Fax:(480)460-2142  |  Brass Rat  |
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This is true.

To my knowledge there is no plans for the voltage to become 240V in Europe. 230V is the standardized voltage throughout Europe.

Yes. 230V from neutral to phase and 400V between phases nowadays.

--
Tomi Engdahl (http://www.iki.fi/then/)
Take a look at my electronics web links and documents at 
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pass (CNC

use current

I watched one of these saws being commissioned once. The do-or-die moment is when the saw generates its _own_ blade-guide by cutting through the load-beam, a 4" square box channel about ten feet long. Made a huge noise and attracted everybody in the factory, fingers in ears and cigarettes on lips. The ceremony is especially important to those who checked blade's axial runout. Wade Hassler