18 gauge wire is rated for 2 amps. That would be more than enough for all the ceiling lights in my house. (LED) However I prefer to wire the lights so that three circuits would serve them all. That way a breaker that trips off would not leave everything in the dark.
Of course there are no breakers with that low a current rating available for a house panel.
Typical is a 200 amp main breaker for the main service and 20 or 30 amp breakers for the branch loads. Some for 120 volt circuits and others for 240 volt circuits. Rarely used are 15 amp 120 volt ones. Thus the typical branch circuit cables are 12 gauge for 20 amps and 10 gauge for 30 amps. The safety ground wire is slightly smaller as it only needs to be adequate to safely trip the protection circuity.
I do realize some places the main wire is fused and goes to all of the outlets in parallel and the outlets are fused. Here all branches are fused at the breaker panel and the mains service goes through a larger breaker in the panel. Typically the is one dual 200 amp breaker for the two hot main lines and 20 or so branch breakers. Branch breakers that are top to bottom next to each other are on alternate mains service. That way you can get 120 or 240 volt service.
Of course there are no breakers with that low a current rating available for a house panel.
Typical is a 200 amp main breaker for the main service and 20 or 30 amp breakers for the branch loads. Some for 120 volt circuits and others for 240 volt circuits. Rarely used are 15 amp 120 volt ones. Thus the typical branch circuit cables are 12 gauge for 20 amps and 10 gauge for 30 amps. The safety ground wire is slightly smaller as it only needs to be adequate to safely trip the protection circuity.
I do realize some places the main wire is fused and goes to all of the outlets in parallel and the outlets are fused. Here all branches are fused at the breaker panel and the mains service goes through a larger breaker in the panel. Typically the is one dual 200 amp breaker for the two hot main lines and 20 or so branch breakers. Branch breakers that are top to bottom next to each other are on alternate mains service. That way you can get 120 or 240 volt service.
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Considering just how rinky-dink common house wiring is down here in Argentina, outages are confined to windstorm disconnections & seasonal overloads.
In fifteen plus years, no over-voltages, but we did have ONE voltage sag & I got out my meter to measure...I think is was a little more than half at 155 VAC.
For our US spec clothes dryer, I had to explain things to a local transformer build house just what was an autotransformer??? A two pole to three pole center tap...I might just tap their minds to create a 250-0-250V, 6.3-0-6.3V, 5.0V-0 tube-amp transformer one of these days.
I've had my fill of flames jetting out of the so-called "outlets" I've run across...We still deal with the unbalanced voltages everywhere, gotta keep on ones toes around here...exploding neighborhood transformers not withstanding.
----------------------------------------------------------------------------Rick...
In fifteen plus years, no over-voltages, but we did have ONE voltage sag & I got out my meter to measure...I think is was a little more than half at 155 VAC.
For our US spec clothes dryer, I had to explain things to a local transformer build house just what was an autotransformer??? A two pole to three pole center tap...I might just tap their minds to create a 250-0-250V, 6.3-0-6.3V, 5.0V-0 tube-amp transformer one of these days.
I've had my fill of flames jetting out of the so-called "outlets" I've run across...We still deal with the unbalanced voltages everywhere, gotta keep on ones toes around here...exploding neighborhood transformers not withstanding.
----------------------------------------------------------------------------Rick...
In fact the middle of the US sits on the “Madrid Fault”
#3 son wife and kids had a 6+ two weeks ago in NorCal.
I've actually made transformers for grid use myself, several kinds of first and secondaries with alu or copper, layers of up to 3mm thick copper foil with 10cm x 2cm connection bars. Biggest was only 3000kva, so probably small stuff to what's in the US, but still.
Only thing is that the 120v transformer must have thicker core winding to provide the same VA rating. The difference between amount of copper in a 120v and a 240v transformer is negligible at best. The actual difference is what happens AFTER the transformer.
Simplification: you can view the voltage drop as a constant, if you have a specific length of cable where the voltage drop is 3v, it is the same 3v loss if the voltage is 120v or 240v. So the % of effective loss is much lower with higher voltages, this is the reason why the grid is operating on high voltage to begin with.
2 Amp circuit breakers are available in France. Nothing special, that is standard common gear.
In home, widely used: 2A 10A 16A 20A 32A.
In home, widely used: 2A 10A 16A 20A 32A.
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It is Volt and kVA... Please. The example with 3V voltage drop is nice but in reality the load will be the same power. For this an equally simplified example: in 120V areas a 120W lightbulb draws 1A. In 240V areas a 120W lightbulb will draw 0.5A. As I is squared (copper losses = Isquared x R x t) the influence of the current is large on copper losses.
So, as you correctly state, the higher the voltage the less losses. For this very reason mains voltage was upped to 230/240V ages ago.
Low current breakers exist in DIN rail format. But ... wiring still needs to be the standardized gauge here (2.5 mm2 for L, N and PE, 1.5 mm2 for switched wire to light points in ceilings). A new house owner may decide to install let's say a few 20W LED fixtures per room and a 16A breaker on that light group....
At the left an old breaker 4A C class, at the right a 16A B class. That specific 4A version is now forbidden, can you tell me why?
So, as you correctly state, the higher the voltage the less losses. For this very reason mains voltage was upped to 230/240V ages ago.
Low current breakers exist in DIN rail format. But ... wiring still needs to be the standardized gauge here (2.5 mm2 for L, N and PE, 1.5 mm2 for switched wire to light points in ceilings). A new house owner may decide to install let's say a few 20W LED fixtures per room and a 16A breaker on that light group....
At the left an old breaker 4A C class, at the right a 16A B class. That specific 4A version is now forbidden, can you tell me why?
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That is why a 2A breaker is rarely used.
A case I am aware of, is in a electric water heater command circuitry: A 2A is used to protect the switch that commutes according to day/night billing.
10A is commonly used for a bunch of lightings.
Breakers below 6A are costlier here, calibration has to be better.
The 4A is a C Class single pole unit. is that why it is banned?
The 4A is a C Class single pole unit. is that why it is banned?
Here in India there is a big incentive towards solar, net metering is used, you pay for the difference between generated power and used power, and the bills become negligible.
Small "bicycle" windmills are available, 500 VA upwards, which can work round the clock, generating power in the dark too.
Power management systems are there to handle the power generated, in order to supply the grid, charge batteries or both, using solar and wind mill supplied power together.
For remote locations, Lead Acid is the preferred battery chemistry. Old truck batteries are also recycled.
So it is gaining popularity, simply as a tax and money break, as tax benefits up to the solar system cost are available on an accelerated basis.
Some states offer a 50% subsidy on the system cost. So you get the system essentially free, as there is a large tax break available, apart from the subsidy.
This has resulted in more reliable power, there is a greenhouse gas saving, and thanks to LED the overall load has come down, but more and more air conditioners are being installed.
No battery farm as yet reported in my state. One is coming in the next state, no idea of status.
Small "bicycle" windmills are available, 500 VA upwards, which can work round the clock, generating power in the dark too.
Power management systems are there to handle the power generated, in order to supply the grid, charge batteries or both, using solar and wind mill supplied power together.
For remote locations, Lead Acid is the preferred battery chemistry. Old truck batteries are also recycled.
So it is gaining popularity, simply as a tax and money break, as tax benefits up to the solar system cost are available on an accelerated basis.
Some states offer a 50% subsidy on the system cost. So you get the system essentially free, as there is a large tax break available, apart from the subsidy.
This has resulted in more reliable power, there is a greenhouse gas saving, and thanks to LED the overall load has come down, but more and more air conditioners are being installed.
No battery farm as yet reported in my state. One is coming in the next state, no idea of status.
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Yeah, I'm just tired of the whole thing, big and small letters all over the place pending on mood, humidity and wind direction or whatever else, and simply stopped caring, so not sorry about that. Should be sufficient to read it in context. Nice to see you squirm over my complete lack of caring, look here: hZ! 😀
At any rate, the voltage drop is a simplification, as stated.
I can phrase it differently if that helps.
A specific cable thickness can carry a certain amount of current safely, double the voltage (as long as it's within spec) and that same cable can still carry the same current. Voltage loss will be the same, but VA capacity is a just a tiny little bit more than doubled.
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Yes the lower voltage delivery does use more current and thus requires thicker branch circuits.
Although much wire gauge is specified by current rating, there are also bits of the electrical code regarding loss. You are allowed 5% voltage loss from the mains power distribution lines into your high current breaker panel and another 5% loss on a branch circuit. It does not matter what the actual voltage can be!
Of course a 240 volt branch circuit at 60 hertz would be the best provided the outlet receptacle cannot be probed with a child’s fingers, knife, fork or similar. Ground fault or similar circuit interrupters do need to be provided to prevent injury.
Here there is also the requirement for arc detection and interruption breakers for sleeping quarters and similar.
Or as a friend getting shocked from a 120 volt line for the first time mentioned it didn’t hurt nearly as much as a 240 volt one! I should mention I have been on job sites where folks were killed by making mistakes. Worst case I know of was a fellow checking to see if the spacing of a 22,000 volt line matched the transformer input terminals on a live line with a metal tape measure. The result killed him and burned down the building.
As far as I know virtually every standard is raising the actual voltage level to increase efficiency. This is done gradually so as to prevent consumers from complaining about burnt out gear. They just assume it is old age. This does affect the use of vintage equipment as much of it is unhappy with the higher voltage.
If you look at small transformer ratings they are often specified for 110 or 220 volt primaries. The idea being they will saturate a bit and deliver the rated secondary voltage correctly, albeit a bit distorted. A lot of older transformers tried to avoid saturation and end up delivering high secondary voltage.
Years ago I did design a 15 kVA and 30 kV transformer. It worked nicely, but I must admit my design was double checked by the manufacturer who was surprised I got it right. Likely due to my university course still including magnetics and transformer design.
Although much wire gauge is specified by current rating, there are also bits of the electrical code regarding loss. You are allowed 5% voltage loss from the mains power distribution lines into your high current breaker panel and another 5% loss on a branch circuit. It does not matter what the actual voltage can be!
Of course a 240 volt branch circuit at 60 hertz would be the best provided the outlet receptacle cannot be probed with a child’s fingers, knife, fork or similar. Ground fault or similar circuit interrupters do need to be provided to prevent injury.
Here there is also the requirement for arc detection and interruption breakers for sleeping quarters and similar.
Or as a friend getting shocked from a 120 volt line for the first time mentioned it didn’t hurt nearly as much as a 240 volt one! I should mention I have been on job sites where folks were killed by making mistakes. Worst case I know of was a fellow checking to see if the spacing of a 22,000 volt line matched the transformer input terminals on a live line with a metal tape measure. The result killed him and burned down the building.
As far as I know virtually every standard is raising the actual voltage level to increase efficiency. This is done gradually so as to prevent consumers from complaining about burnt out gear. They just assume it is old age. This does affect the use of vintage equipment as much of it is unhappy with the higher voltage.
If you look at small transformer ratings they are often specified for 110 or 220 volt primaries. The idea being they will saturate a bit and deliver the rated secondary voltage correctly, albeit a bit distorted. A lot of older transformers tried to avoid saturation and end up delivering high secondary voltage.
Years ago I did design a 15 kVA and 30 kV transformer. It worked nicely, but I must admit my design was double checked by the manufacturer who was surprised I got it right. Likely due to my university course still including magnetics and transformer design.
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It is best not to touch either 120 or 240V. I am not very afraid of 230V but I do have a healthy paranoia with 400V 3 phase systems and 400...500V DC systems. Or the absolute worst in low voltage... +/- 400V high power DC systems with batteries. Imagine the risks of let's say replacing one of the middle batteries in the positive string. I have had small shocks from capacitive coupling to the floating battery rack.
With 10 kV or higher it is plain fear (despite calculated risk) and therefor being cautious and double thinking before doing. Most will know the dry mouth despite a good cup of coffee. Even when working safe things can go wrong on various levels. The switch itself breaking down is not uncommon as mid voltage switchgear is not meant for many switch actions. One phase missing, a new but leaking cable etc. Many (including me) underestimate the sound levels of switchgear.
With 10 kV or higher it is plain fear (despite calculated risk) and therefor being cautious and double thinking before doing. Most will know the dry mouth despite a good cup of coffee. Even when working safe things can go wrong on various levels. The switch itself breaking down is not uncommon as mid voltage switchgear is not meant for many switch actions. One phase missing, a new but leaking cable etc. Many (including me) underestimate the sound levels of switchgear.
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Here In Canada, we don't waste time with 277/480V... We use 347/600V. My street is supplied with 27.6kV.
I have a 100A service in a 380 sqft appartement. No fuses or breakers lower than 15A exist here (for electrical panels).
If I designed a system for residential, it would be 12VDC and 600VDC. LV triggers for lights etc... That would get rid of all that damned hum.
I have a 100A service in a 380 sqft appartement. No fuses or breakers lower than 15A exist here (for electrical panels).
If I designed a system for residential, it would be 12VDC and 600VDC. LV triggers for lights etc... That would get rid of all that damned hum.
I am so cautiou about high voltage that I got a project never finished.
I wanted to make my own oscilloscope from scratch. So I bought a CRT, fast penthodes, built a case, bought a high voltage transformer and caps. It was asking for a pretty high voltage for post acceleration.
Then I started building the PSU....But, I though: Only one mistake and it is likely, I will kill myself.
So I gave up.
May be thanks to this decision, I am here to write this.
While moving stuff recently, I found this unfinished project in a basement, a more than 50 years old memory.
I wanted to make my own oscilloscope from scratch. So I bought a CRT, fast penthodes, built a case, bought a high voltage transformer and caps. It was asking for a pretty high voltage for post acceleration.
Then I started building the PSU....But, I though: Only one mistake and it is likely, I will kill myself.
So I gave up.
May be thanks to this decision, I am here to write this.
While moving stuff recently, I found this unfinished project in a basement, a more than 50 years old memory.
I got 950V from a scope once... I'm still here...
Lucky for me the current only ran through my fingers.
Lucky for me the current only ran through my fingers.
One sunny summer day I arrived home from work and while pulling up to my house everything looked wet. No clouds in sight. Then I look up and see liquid dripping from the pole transformer. I guess something went wrong and the antique transformer decided to violently vent all its oil. Oddly enough we still had power. I called the power company and they didn't seem too concerned as the woman took down my information. Figuring that piece of paper would be at the bottom of the pile I called 911 to get the ball rolling. The power company sent out a cleanup crew to scrub down my driveway and the street and cut back the vegitation that was covered in oil. While this was going on they replaced the transformer. Makes me wish I had a security camera at the time. That oil release must have been a sight.
Looks to be an upcoming market for the bucking transformer topology. They bring it up, we bring it back down for ya!
Just watched a YT vid of a guy rebuilding a truck battery. Replaced and re-laced all the plates inside, put new posts on and resealed the plastic case, put new electrolyte. Pretty impressive work.
Then I started vid binging on how in other countries, people fix stuff that most here in the US would throw in the towel on; put to the junk yard. You can tell it's pretty much done right too.
Truck and car batteries that won't crank are used here for backup, larger ones for inverters, smaller ones for stalls selling vegetables, food and so on.
Somebody here even rents the batteries out to these small carts and stalls, charges them up, delivers, takes back to recharge after exchanging them.
A fruit cart has a solar panel on the roof...off grid power to LED arrays...
Somebody here even rents the batteries out to these small carts and stalls, charges them up, delivers, takes back to recharge after exchanging them.
A fruit cart has a solar panel on the roof...off grid power to LED arrays...
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