Is there any 110 volts AC in the USA anymore?

[gary350]

Another forum everyone talks about 110 volt AC at home. Electric outlets are 110 volts, lights are 110 volts, circuit box is 220 volts. Small appliances like fan, toaster, electric mixer, coffee maker are 110 volts. Large appliances like kitchen stove, hot water heater and electric drier are 22o volts.

My volt meter shows I have 120 volts at home. We had 122 volts at work and 489 volts in the factory. My parents house was 120 volts in high school. The camp ground is 120 volts. Motels are 120 volts. Relatives and friends house are 120 volts. The college dorm and houses I later lived in were 120 volts that was 50 years ago.

Is there any place in the USA that is still 110 volts?

 

[MaxHeadRoom78]

I think you will find that most of N.A. is now 120/240 service.
Canada definately is.
Max.

 

[KeepItSimpleStupid]

The "elders" may just call it 110/220 because that's what it was long ago. Stuff was tested at 117 V. The voltage crept up.
You'll find 240/120 for split phase/single phase and either 120/208/277 (Y) or 120/240 (Hi leg delta) for 3 phase power.
277 is used for lighting, when the supply is "Y".

=sqrt(3)*277 = 480

 

[gary350]

I did some of the electrical wiring at work for 45 years. Everything in the factory was 120, 240, 277, 480 volts. I never understood why 277 was for lights only. Lights also come 120, 240 and 480 volts. Every factory needs a completely separate 277 volt circuit box and wiring in the building only for lights. The lights in the factory and office were all 277v. Lights in the factory were 240/277/480 volt high pressure sodium.

Any way the other forum kills me with everyone talking about 110 volts. If I type a reply to a thread I always type 120 volts and 240 volts then the forum moderator edits my post and changes it to 110v and 220v. LOL. I wonder if I am driving the moderator nuts typing correct voltages, LOL.

 

[BobW]

The principal function of the first electric power utilities was to provide power for electric lighting. The manufacturing tolerance for early carbon filament lamps was not very tight. So after their manufacture, the lamps were sorted into 110v, 115v, and 120v bins. Power utilities were encouraged to standardize on different voltages to create a market for all of the lamps, resulting in different nominal supply voltages in different regions. After the introduction of tungsten filament lamps in the 1910's, which could be manufactured to much tighter specs, there was no longer a need for this variation, and lamps were standardized at 115 volts.
The utilities eventually adopted 120 volts as the supply standard (allowing for a 5 volt drop in the distribution system).

Source: The late Alan Douglas, and AIEE Transactions from the 1920's.

 

[KeepItSimpleStupid]

Look at: https://en.wikipedia.org/wiki/Mains_electricity

In the United States[8] and Canada,[9] national standards specify that the nominal voltage at the source should be 120 V and allow a range of 114 V to 126 V (RMS) (−5% to +5%). Historically 110 V, 115 V and 117 V have been used at different times and places in North America. Mains power is sometimes spoken of as 110 V; however, 120 V is the nominal voltage.

Hopefully, I'll be back with some more related stuff. In Bold is what I said.

 

[Ratchit]

Another forum everyone talks about 110 volt AC at home. Electric outlets are 110 volts, lights are 110 volts, circuit box is 220 volts. Small appliances like fan, toaster, electric mixer, coffee maker are 110 volts. Large appliances like kitchen stove, hot water heater and electric drier are 22o volts.

My volt meter shows I have 120 volts at home. We had 122 volts at work and 489 volts in the factory. My parents house was 120 volts in high school. The camp ground is 120 volts. Motels are 120 volts. Relatives and friends house are 120 volts. The college dorm and houses I later lived in were 120 volts that was 50 years ago.

Is there any place in the USA that is still 110 volts?

You might like to peruse this thread starting at post #47. https://www.electro-tech-online.com/threads/a-pedantic-question.135826/page-3

Ratch

 

[KeepItSimpleStupid]

This https://www.school-for-champions.com/science/ac_world_volt_freq.htm#.VmpF2nqYO1E one isn't too bad.

It also explains the evolution briefly.

 

[KeepItSimpleStupid]

Here's https://www.ccontrolsys.com/w/Electrical_Service_Types_and_Voltages a brief review of electrical distribution systems. It shows where 277 comes from.

 

[Gasboss775]

This has cleared up a few things for me. As a non American I was a little thrown by the whole 110 / 117 / 120 volt thing. It was even weirder here in the UK. With voltages once covering the range of 200 - 250 volts with DC in some places when power was supplied from local sources prior to the advent of the national grid. It is now standardised as 240V / 50Hz ( 415V for 3 phase )

 

[KeepItSimpleStupid]

I worked in a building that had 240 3 phase and it was probably hi-leg delta. We moved to a place where 208/Y was installed or at least that was the distribution. 277 was available for lighting. Ventilation and 32 water to air heat pumps were three phase 4xx. For the most part everything worked except we had to change some heating elements from 240 to 208 on some diffusion pumps and the people that designed the electrical forgot the neutral wire that the equipment needed. One piece of equipment needed 90 A 3 phase 208 and another took 200 A 208 3 phase.

In general, 3 phase is not used for residential, but some utilities allow it.

A friend had a business where 2-phase was used at one time and he had some motors to prove it.

The house I live in is primarily natural gas/electric. Air conditioning wasn't common back in the 1960's. 240 was installed, but not used for anything.
The only 240 V thing is the air conditioner.

Japan, apparently, has 100 V is some places. So, some switchmode power supplies are 95 to 285 V input which accommodates 100 and 277 V. Many SMPs supplies just auto switch from 120/240. They create about 400 VDC internally from either half or full wave rectification of the 220 or 120 mains.

 

[chemelec]

It really does not matter if it is 110, 117 or 120 Volts.
These are Nominal Ratings and a 110 Volt Appliance will still operate OK at 120, or Visa Versa.
A 10% Change is Acceptable.

According to our Utility Company, the Nominal Voltage is 117.5 VAC, but depending on the time of day and amount of use at a give time, it can vary considerably.
Varying Current Loads and Wire Resistance can change these voltages, even in Two different rooms in a House.

 

[Gasboss775]

According to our Utility Company, the Nominal Voltage is 117.5 VAC, but depending on the time of day and amount of use at a give time, it can vary considerably.

My understanding is that the frequency of the mains supply is far more carefully regulated than that of the voltage. I assume this is to ensure synchronisation of different sources on the power grid.

 

[chemelec]

My understanding is that the frequency of the mains supply is far more carefully regulated than that of the voltage. I assume this is to ensure synchronisation of different sources on the power grid.

Yes the Frequency is Quite Precisely Regulated.
Partly for That reason and also to Control Older Clocks and other Items that are Frequency Dependant.

 

[Diver300]

My understanding is that the frequency of the mains supply is far more carefully regulated than that of the voltage. I assume this is to ensure synchronisation of different sources on the power grid.

I don't think it works like that. When a generator is about to be connected to the grid, it has to be synchronised so that the phase is correct, before the connection is made.

Once the connection is made, the generator is effectively locked to the rest of the generators on the grid, and the entire grid will run at exactly the same frequency. If one generator gets ahead, its prime mover (usually a water/gas/steam/wind turbine) becomes loaded more, and therefore slows down.

It is a bit like two riders on a tandem. The chain that joins the two sets of pedals together keep both riders pedalling at the same rate. The grid keeps all the prime movers synchronised.

The frequency is kept within limits so that the loads run at the correct speed. There is a much tighter limit on the total cycles for a day than for a second, so that synchronous clocks don't drift, and if they slow a bit during the day, they catch up at night.

 

[schmitt trigger]

Edison came up with 110 volt nominal, because that was the highest DC level he could interrupt safely with the available equipment.
With the advent of AC, 110 volt was kept for compatibility. The voltage was increased slightly to 120 volt later on.

But colloquial terms don't die easily, and people still refer to 110 volt.

 

[Tony Stewart]

The regulators have a criteria of 5% for generation and transmission and 5% for distribution.
I find in Canada they tend to be on the positive side of 120 with 127 nominal here for me.

Maybe our dozen or so house sharing of a transformer demand side is low most of the time, maybe they want to increase revenue a few %

Checking with Hydro One specs for some customer transformers, I read the following for different Types of Control Voltage
Nominal 125 V dc
Closing Range 90-140 V dc
Tripping Range 70-140 V dc


"Hydro One operates all voltage regulating devices on its distribution system to 125V ±1.5V on a 120V base." Without Distributed Generators ( e.g. wind, solar etc ) the short-term voltage fluctuation on Hydro One feeders are well below 1%, or half of the dead band of voltage regulating facilities. With DG's the minute to minute fluctuation has been seen to be 20~30%."

 

[KeepItSimpleStupid]

More detailed research says that it's related to the fabrication of Edison's ARC lamp and it's ideal voltage in DC.

 

[schmitt trigger]

I never understood why 277 was for lights only. Lights also come 120, 240 and 480 volts. Every factory needs a completely separate 277 volt circuit box and wiring in the building only for lights. The lights in the factory and office were all 277v. Lights in the factory were 240/277/480 volt high pressure sodium.
LOL.

277 is the phase to neutral voltage of a 480 volt Star connected three phase system.
Since 480 volt is a widespread industrial range, 277 volt is also very common voltage for industrial illumination.

 

[Tony Stewart]

Due to the SCR effect (aka avalanche arc) of ionized air, AC contacts can switch higher currents than DC for the same voltage due to the zero crossing quenching of arcs.

Relay contacts are always derated for AC motors and DC due to arcing during shutoff vs Resistive loads on AC (heaters)