Inverter.........!

[audioguru]

Use simple addition to add up the rated current of everything that is turned on in your house. But things like a CRT TV has a current that varies due to the brightness.

 

[koolguy]

No sir, i want maximum value of the line supply, as my teacher told that it depend on load resistance as the resistance decrease the will be infinite that i wan to conform how it possible as if load is of 1.5ohm so, the will be 146amp is this possible..!

 

[audioguru]

No sir, i want maximum value of the line supply

What is a "line supply"?

as my teacher told that it depend on load resistance as the resistance decrease the will be infinite that i wan to conform how it possible as if load is of 1.5ohm so, the will be 146amp is this possible..!

if your electricity is 220VAC then a load of only 1.5 ohms causes a current of 230/1.5= 146.7A.
It is simple Ohm's law and simple arithmatic.

 

[chemelec]

Sir, I want to calculate current of ac house line supply not of Battery...!

The AC Suppy of a House Circuit is Determined by the House Fuses of your Electrical Box.
On our 110-220 AC Lines, Most Outlet Lines in North America are rated at 15 Amps.
Hot Water and Dryer Lines are usually 40 Amps, and the Main Fuses are typically between 60 and 200 Amps.

Not Sure What your Voltages or Fuse Ratings are Where you live? But Just LOOK at the Fuses or Circuit Breakers in your Main Electrical Box.

 

[koolguy]

The AC Suppy of a House Circuit is Determined by the House Fuses of your Electrical Box.
On our 110-220 AC Lines, Most Outlet Lines in North America are rated at 15 Amps.
Hot Water and Dryer Lines are usually 40 Amps, and the Main Fuses are typically between 60 and 200 Amps.

Not Sure What your Voltages or Fuse Ratings are Where you live? But Just LOOK at the Fuses or Circuit Breakers in your Main Electrical Box.

if we connect no fuse and then we find max. current, i thick the supply coming in house have some rated current as it come from transformer so, how can it be possible to have current like 146amp if we see an example like battery it has max. current rating on it and can't be increase by decreasing load, pls clear my doubt.

 

[carmusic]

just borrow an ampmeter from an electrician (clamp on), turn everything on in your house and measure current.

 

[chemelec]

if we connect no fuse and then we find max. current, i thick the supply coming in house have some rated current as it come from transformer so, how can it be possible to have current like 146amp if we see an example like battery it has max. current rating on it and can't be increase by decreasing load, pls clear my doubt.

What makes you think a Car Battery can ONLY DELIVER 146 Amps?
Actually a Car Battery can deliver Several THOUSAND AMPS on a Low Resistance Load. But Only for a Few Seconds.
Not sure What Rating your Looking at, But Probably an "Amp Hour" Rating or a "Cold Crank" Rating?.

As to Your House Current, If you Bypass the Fuses, It can Also Deliver VERY HIGH CURRENT on a very low resistance load.
It Could Actually MELT the Wires coming to your house.

But WHAT IS THE POINT TO THESE SILLY QUESTIONS?

 

[koolguy]

But WHAT IS THE POINT TO THESE SILLY QUESTIONS?

I was asking this question b'coz my teacher was explaining dc motor as he was telling that starting motor without starter will damage it as the field winding resistance is very low, he was giving example on it that's why i was asking.

 

[koolguy]

Pls clear my one more doubt as every one say DC is more harmful then AC why we get shock in ac but when we simply touch both terminal of dc we can't get shock,why...?

 

[chemelec]

Pls clear my one more doubt as every one say DC is more harmful then AC why we get shock in ac but when we simply touch both terminal of dc we can't get shock,why...?

Before you can get a Shock, you need to have Enough Voltage to Overcome your Skin's Resistance so a reasonable amount of Current will Flow. The Greater the Current Flow, the More Dangerous the Shock!
12 Volts from a Battery is NOT Enough Voltage to allow current to flow though your skin.
(And 12 Volts AC is Also Not enough Voltage to give you a Shock.)

Typically, Voltages GREATER than 48 Volts (AC or DC) will become Dangerous.
But Not Everyone has the Same Skin Resistance, so this can Vary Somewhat.

 

[koolguy]

i have diode Fr2007 i have solder it out from ups i searched in google, but not get it link pls tell what is this..?

 

[Transistorman]

Here in india power outages are very common... Typically every household invariably in any city all thru the country faces 2 to 3 hours of outage daily.. Simply because we dont have sufficient generators to feed all people... So they shed loads in turns.. Power from a generator for one place in morning and for some other place in evenings...!

@audioguru: I am surprised to know that its a surprise for you...!

here in indonesia

outages are really common

usually it takes 8 - 10 hours until it get on again

 

[koolguy]

i have diode Fr2007 i have solder it out from ups i searched in google, but not get it link pls tell what is this..?

Pls reply..!

 

[chemelec]

As near as I can tell, there is NO SUCH PART NUMBER!
tHERE IS AN FR2006 AND FR2008, BUT NOT AN FR2007!

 

[koolguy]

In 5kw ups if we connect 50 watt load that mean it will continue for 100hrs. is this true pls clear my doubt.

 

[Ubergeek63]

In 5kw ups if we connect 50 watt load that mean it will continue for 100hrs. is this true pls clear my doubt.

you confuse rating with run time. there is a power rating AND a run time. a typical cheap UPS supplies 500 watts for 3 minutes and would supply your 50W load for about 30 minutes. this does not hold true for low loads since they will be dominated by the UPs's own electronics.

you need to start from what MUST be kept running and for how long... you will probably be dissuaded from this fruitless venture when you see the cost of the batteries for what you are proposing

to keep your laptop (50W) going during your 10Hr blackout will cost 200 USD just for the batteries.

 

[audioguru]

Canada has an extra nuclear generating station on "standby" in case it is needed. It was not needed last year so the costs of having it ready was very high. It also might not be needed this year but next year it will probably be used so that there are no blackouts.

 

[koolguy]

ok, i have 625VA UPS for computer, but if i calculate it power given by battery to ups is P=12*(less than 20amp.) how can it give power output of 625VA As 625=220*I(amp).

 

[koolguy]

one more question I was measuring output current of transformer of 18V, but multimeter fail to show it's output current but on connecting rectifier it show near by 7Amp. pls tell any relation for calculating ac current with same meter.

 

[audioguru]

I have 625VA UPS for computer, but if i calculate it power given by battery to ups is P=12*(less than 20amp.) how can it give power output of 625VA As 625=220*I(amp).

625VA might be the max allowed momentary peak output power. Its continuous allowed output power might be only 300VA.

If it operates from a 12V battery, is 80% efficient and has a 300W load then it draws 375W from the battery so the battery current is 375/12= 31.25A.
If it operates from a 12V battery, is 80% efficient and has a 625W load then it draws 781.3W fom the battery so the battery current is 781.3/12= 65.1A.
625W at 220V has a current of 625/220= 2.84A.

You forgot to tell us the waveform shape. If it is a simple square-wave or a modified sine-wave then you must measure its voltage and current with a true-RMS meter because an ordinary cheap meter is calibrated for a perfect sine-wave.