amp and watts

[nandac]

by amp i don't mean amplifier, but the measure of electricity commonly used in plugs etc.

in my apartment's switch board, there is a switch for each room. some of them read 6 amps and some read 16 amps. our electrician says that the 16 amp switches are for bathrooms, kitchens etc which use high load electrical appliances - water heaters etc.

according to him, a 6 amp switch can only generate a certain amount of power - 700 watts or so. he says that if i have a 1000 watts step down transformer and the room's switch reads 6 amps, then it is quite likely that the 1000 watt step down transformer will not get that much current.

but in the raksha step down transformer that i use, the input socket seems to use only the standard small (5 amp?) plug. or am i mistaken in that 16 amps plugs are bigger?

so question here is regarding the correlation between amps and watts : how much is the max power a 5 amp switch can handle/generate?

our electrician says that he can swap the 6 amp switch for a 10 amp switch which according to him is now approved by the bangalore electricity board.

appreciate any insights.

 

[reignofchaos]

5A x 220V = 1100W peak output in theory assuming everything else works. You'd however be limited by your MCB/Switch if it is lower capacity.

Audio equipment would never reach these limits. However things like multiple airconditioners will definitely cause switches to trip if they are not up to it. I had to replace quite a few switches when the house got airconditioned. Turning two ACs on would cause a trip otherwise.

 

[jls001]

our electrician says that he can swap the 6 amp switch for a 10 amp switch which according to him is now approved by the bangalore electricity

Not a good idea. Amp rating is not just the plug and switch. There has to be 16A rated wiring behind it. You don't just slap a 16A point on a 5A wiring. Otherwise, if you draw higher than 5A from that plug, the wire would start heating up. In worst case, it can lead to meltdown and fire.

5A/6A and 16A are of different sizes. Compare the 3-pin plug of your washing machine (which is usually 16A) and that of any lower-powered device (which is usually 5A, and smaller compared to 16A).

The 10A the electrician is referring to is probably MCCB. Domestic switches in India are either 5/6A or 16A, not 10A.

 

[cmsajith]

The electrician is wrongly adding the power factor (might have heard this term from somewhere else) to the switches also.

 

[alpha1]

by amp i don't mean amplifier, but the measure of electricity commonly used in plugs etc.

in my apartment's switch board, there is a switch for each room. some of them read 6 amps and some read 16 amps. our electrician says that the 16 amp switches are for bathrooms, kitchens etc which use high load electrical appliances - water heaters etc.

according to him, a 6 amp switch can only generate a certain amount of power - 700 watts or so. he says that if i have a 1000 watts step down transformer and the room's switch reads 6 amps, then it is quite likely that the 1000 watt step down transformer will not get that much current.

but in the raksha step down transformer that i use, the input socket seems to use only the standard small (5 amp?) plug. or am i mistaken in that 16 amps plugs are bigger?

so question here is regarding the correlation between amps and watts : how much is the max power a 5 amp switch can handle/generate?

our electrician says that he can swap the 6 amp switch for a 10 amp switch which according to him is now approved by the bangalore electricity board.

appreciate any insights.

Its not switch but either a fuse or a circuit breaker.
6A circuit breaker means, anything over 6A will break the circuit.

Hence, its a safety device.


Now why do you need 6A for some and 16A for others?
Because stuff like Heater, Geyser, Airconditioner, Refrigerator etc draw very high currents.

Usually more than 2500W = 2500/250 = 10 Amps.
Therefore those devices have a separate 16 A circuit breaker or fuse wire.

If you would observe (by peeking in, after opening the panel), these also carry thicker wires, which allow higher currents without getting hot.

-x-

IF you replace your 6A breakers/fuses with 16A - what happens is that it will allow current till 16A without breaking the circuit.

Now if you are using an equipment rated for 1000W = 4 A, it can easily run on 6A breakers/fuses.
So why do you want to install a 16 Amp one?

 

[nandac]

thanks for all the input guys. as alpha noted i was talking about the circuit breaker - sorry i didn't know the term. my electrician replaced the 6 amp one for three rooms with 10 amp ones. said there will not be any issue.

 

[nandac]

>Now if you are using an equipment rated for 1000W = 4 A, it can easily run on 6A >breakers/fuses.
>So why do you want to install a 16 Amp one?

i have american equipment so need a step down.

for an amp which consumes 300 watts, i initially bought a 500 watt step down. but that clearly didn't give the amp the necessary power and you could hear it - in the harshness of the sound.

so on suggestion from a forum member, i bought a 1000 watt step down and that solved the issue. the sound became more open and clearer losing the harshness.

so for my hp setup, i use a av receiver, a sub - each of which consumes like 350 watts. so going by my previous experiment, if i needed a 2000 watt stepdown (1000 each) the 6 amp circuit breaker will not do, right?

so that's why i went for the 10 amp one. my electrician warned me about putting 16 amp ones saying it might trip, wires might burn etc. but said 10 amp should not cause any issue.

 

[Thad E Ginathom]

according to him, a 6 amp switch can only generate a certain amount of power - 700 watts or so. he says that if i have a 1000 watts step down transformer and the room's switch reads 6 amps, then it is quite likely that the 1000 watt step down transformer will not get that much current.

"generate" is obviously the wrong word, and I'm surprised at an electrician talking like this. You can draw as much current as you like from a 5-amp socket ... but it will soon start melting as you exceed its rating, and I mean soon: I burnt out two 5-amp sockets with a set of garden christmas lights, that I found to be drawing 7 amps, before I got the point. Circuit breakers are supposed to prevent this from happening.

Agreed about the house cabling: if that is not sufficiently heavy-weight for the current, then it will be a fire risk. Again, fuses and circuit breakers are supposed to prevent this happening: changing the socket/breaker without checking the cable is very dangerous.

 

[alpha1]

>Now if you are using an equipment rated for 1000W = 4 A, it can easily run on 6A >breakers/fuses.
>So why do you want to install a 16 Amp one?

i have american equipment so need a step down.

for an amp which consumes 300 watts, i initially bought a 500 watt step down. but that clearly didn't give the amp the necessary power and you could hear it - in the harshness of the sound.

so on suggestion from a forum member, i bought a 1000 watt step down and that solved the issue. the sound became more open and clearer losing the harshness.

so for my hp setup, i use a av receiver, a sub - each of which consumes like 350 watts. so going by my previous experiment, if i needed a 2000 watt stepdown (1000 each) the 6 amp circuit breaker will not do, right?

so that's why i went for the 10 amp one. my electrician warned me about putting 16 amp ones saying it might trip, wires might burn etc. but said 10 amp should not cause any issue.

Well the risk still remains.

The wires are designed for 6 amps.
The breakers were for 6 amps.

So if there were 8 amps flowing through (by mistake - usually due to shorting or leakage), then the circuit would've broken.

In the current case, the 8 amps will keep flowing because the breaker is now for 10 amps.

So, there is a possibility that the wire designed for 6 amps may not be able to stay cool with higher amps.

Of course there is always a design margin as well as margin of safety - so a wire designated for 6 amps may take upto 10 amps - but then this is India.
And we love to go for lowest priced options.
The person who built your home was also the same.
And he would've put sub-standards wires ...

 

[alo1269]

Sorry, Havells India has 10Amp MCBs. in B series. This is for your information. Now it is available in C series too.

 

[asliarun]

Please also get an RCB installed, if you don't have it already. It is quite literally a life saver.

It is designed to trip if it detects a short circuit or if someone gets an electric shock. It is also designed to be fast enough so it trips before a shock can cause serious damage to a human being.

The reason why I say this is because electricians often play fast and loose and are more often interested in "getting the job done" even if it means compromising safety.

RCB might cause you a fair amount of initial hassle especially if you have electrical appliances that are already quietly shorting without your knowledge (washing machines etc.), but they are well worth in the long run because they not only protect you, but also highlight appliances that are misbehaving and force you to get them fixed.

 

[just4kix]

In some of the replies above, there is a lot of inaccuracy.

First of all, know the basics:

- voltage is sourced, i.e., provided
- current is drawn, i.e., pulled

A 5A socket or a 15A socket will not provide 5A current or 15A current, but it will provide 230V voltage. How much current will be drawn is determined by the resistance or impedence of the connected circuit. The power wattage equation for DC (direct current) circuit is:

W = V x I or W = I x R

So I = V/R.

But for AC (alternating current), the equation is slightly different. Because the AC is a sinusoidal wave, the voltage is not constant. Hence power factor comes into picture. This power factor is the area under the sine wave and is roughly 0.66667. So in case of AC, the power equation is:

W = V x I x 0.66667 or W = I x R x 0.66667

So I = (0.66667 x V)/R.

This means that a 5A socket is rated to provide a maximum power 767W. So what the electrician told the OP is correct.

-----

Now what happens if you connect a 1000W rated equipment to a 5A plug. This means that the equipment will try to draw 6.52A of current from the socket. This will cause the copper wires to heat up. Generally in a new house where electrical architect has designed for safety, such small(er) overdrawing is allowed. This is because ELCB will not trip at this point. The ELCB is fitted at the main entrance where 15A is the rating. But the plugs of the equipment rated 1000W will heat up slightly.

Hence as a precaution, never use any equipment that draws more than 750W in a socket rated 5A.

-----

Audio equipment sound output power is different. An amplifier that says 150W per channel is meaning sound power and not electrical power. Sound power equation is completely different. A 150W sound power is not equal to 150W of electrical power.

 

[alpha1]

But for AC (alternating current), the equation is slightly different. Because the AC is a sinusoidal wave, the voltage is not constant. Hence power factor comes into picture. This power factor is the area under the sine wave and is roughly 0.66667.

Are you even serious?

When we say 250V AC = we always means 250 Vrms AC.
Please note RMS = root mean square value.
Which means you can directly use the P = VI = IR

Power factor is entirely different thing, and there is no point in bringing that in.

And NO, the power factor is not 2/3 because of being a sine wave. Power factor comes into picture because of inductance and capacitance in the ac circuit which causes a lead/lag between the voltage and current. Which is not the point of discussion of this thread. We can have a perfectly power factor of UNITY even with sine waves ...

***

An amplifier that says 150W per channel is meaning sound power and not electrical power. Sound power equation is completely different. A 150W sound power is not equal to 150W of electrical power

Amplifiers ALWAYS are rated based on the electrical power they delivery. Which may be slightly less than the electrical power they consume because of slight inefficiencies due to the losses in the circuit.

What is sound power? Did you mean the audio waves emanating from the speakers? Well that power can only be determined by the speakers, because the driver efficiency determines how much of electrical power from the amplifier gets converted to audio power in the speaker.

 

[Thad E Ginathom]

Amplifiers ALWAYS are rated based on the electrical power they consume. They have no means of knowing the audio power, since audio power is unleashed by the speakers/drivers...

I thought they were rated by the power that they can deliver to the speakers, hence quoted depending on impedance. For a given power delivered, what SPL comes out of the speakers then depends on their efficiency.

 

[just4kix]

Are you even serious?

When we say 250V AC = we always means 250 Vrms AC.
Please note RMS = root mean square value.
Which means you can directly use the P = VI = IR

Power factor is entirely different thing, and there is no point in bringing that in.

And NO, the power factor is not 2/3 because of being a sine wave. Power factor comes into picture because of inductance and capacitance in the ac circuit which causes a lead/lag between the voltage and current. Which is not the point of discussion of this thread. We can have a perfectly power factor of UNITY even with sine waves ...

It ultimately comes to the same thing. Inductance and capacitance is result of the sinusoidal wave form. P = VI = IR does not hold true for AC. It is for DC only. For AC, power factor must be considered. Power factor is defined as the ratio of the real power flowing to the load to the apparent power in the circuit.

An amplifier that says 150W per channel is meaning sound power and not electrical power. Sound power equation is completely different. A 150W sound power is not equal to 150W of electrical power

Amplifiers ALWAYS are rated based on the electrical power they delivery. Which may be slightly less than the electrical power they consume because of slight inefficiencies due to the losses in the circuit.

What is sound power? Did you mean the audio waves emanating from the speakers? Well that power can only be determined by the speakers, because the driver efficiency determines how much of electrical power from the amplifier gets converted to audio power in the speaker.

Consider the Denon ACR-1912. It can deliver 125W x 7 when connected to 6 ohms speakers (90W x 7 with 8 ohms speakers). The peak power cosumption of this AVR is 460W (230V/50Hz). As you can clearly see that sound power is much more than the electrical power.

 

[alpha1]

I thought they were rated by the power that they can deliver to the speakers, hence quoted depending on impedance. For a given power delivered, what SPL comes out of the speakers then depends on their efficiency.

Corrected.

It ultimately comes to the same thing. Inductance and capacitance is result of the sinusoidal wave form. P = VI = IR does not hold true for AC. It is for DC only. For AC, power factor must be considered. Power factor is defined as the ratio of the real power flowing to the load to the apparent power in the circuit.

There is a reason why we use the RMS figure for voltage.
What is the definition of Vrms?

And let us come to the point about power factor = 2/3. How can you, sitting over internet, decide that the Nandac's house has a PF of 2/3? Without even knowing the inductance and capacitance load of his house.

I don't like repeating myself, but you conveniently ignore the unity power factor point:
With sinusoidal wave AC circuit, you can have a perfect unity power factor.
How do you explain that, while claiming a power factor = 2/3 for ALL ac circuits?

Consider the Denon ACR-1912. It can deliver 125W x 7 when connected to 6 ohms speakers (90W x 7 with 8 ohms speakers). The peak power cosumption of this AVR is 460W (230V/50Hz). As you can clearly see that sound power is much more than the electrical power.

Which simply means how much of marketing bull scat Denon has put forth.
Do you imply that Denon ACR1912 consumes only 460 watts of electricity, but magically produces 125x7= 875 watts of audio power???

Where are the extra 415 watts coming from? There is no audiophoolic mumbo jumbo here ... just plain physics

 

[just4kix]

Ok. Peace be with you.

Sent from my GT-I9100G using Tapatalk 2

 

[shanmune]

Which simply means how much of marketing bull scat Denon has put forth.
Do you imply that Denon ACR1912 consumes only 460 watts of electricity, but magically produces 125x7= 875 watts of audio power???

Where are the extra 415 watts coming from? There is no audiophoolic mumbo jumbo here ... just plain physics

[/QUOTE]

I think all of you might be aware of the the reality about the power consumption/total power output on all channels of all the AV receivers.
I am just re-iterating the point you know ...
AVR1912 cannot or does not produce 125x7 = 875 watts of electrical power (is it the audio power ??? no ...) with all the 7 channels driven. If we roughly estimate, the total power )with all 7 channels driven simultaneosly) from all the 7 channels will not exceed (60x7 = 420w) -- assuming 6 ohms impedance. 60 watts/channel (with all the channels driven) itself is too high for AVR1912's ability, but I just used it for the discussion sake. So the actual electrical power output even with all the channels driven at the same time will not exceed 420 watts. From that perspective/calculation, the total power AVR1912 should be the power output on the 7 channels (420w) + internal power losses (as heat energy) should be less than 500 watts (which is nearly around 460 watts).

 

[koalatrunk]

In some of the replies above, there is a lot of inaccuracy.

First of all, know the basics:

- voltage is sourced, i.e., provided
- current is drawn, i.e., pulled

A 5A socket or a 15A socket will not provide 5A current or 15A current, but it will provide 230V voltage. How much current will be drawn is determined by the resistance or impedence of the connected circuit. The power wattage equation for DC (direct current) circuit is:

W = V x I or W = I x R

So I = V/R.

But for AC (alternating current), the equation is slightly different. Because the AC is a sinusoidal wave, the voltage is not constant. Hence power factor comes into picture. This power factor is the area under the sine wave and is roughly 0.66667. So in case of AC, the power equation is:

W = V x I x 0.66667 or W = I x R x 0.66667

So I = (0.66667 x V)/R.

This means that a 5A socket is rated to provide a maximum power 767W. So what the electrician told the OP is correct.

-----

Now what happens if you connect a 1000W rated equipment to a 5A plug. This means that the equipment will try to draw 6.52A of current from the socket. This will cause the copper wires to heat up. Generally in a new house where electrical architect has designed for safety, such small(er) overdrawing is allowed. This is because ELCB will not trip at this point. The ELCB is fitted at the main entrance where 15A is the rating. But the plugs of the equipment rated 1000W will heat up slightly.

Hence as a precaution, never use any equipment that draws more than 750W in a socket rated 5A.

-----

Audio equipment sound output power is different. An amplifier that says 150W per channel is meaning sound power and not electrical power. Sound power equation is completely different. A 150W sound power is not equal to 150W of electrical power.

This was very helpful. Wanted to confirm one thing:
I have a 16 amp socket in my room, which also accepts 6 amp plug. (Screenshot attached)

I was thinking of connecting a extension board to this, one with individual switches, which can accept max 1000W of current.

So if I understood your post correctly, I can connect my extension board here, it will only draw as much current as it needs - more than 6A can provide, but it will do so only when the plugs connected to the extension board need it.

In other words, as long as I don't connect more than 1000W of power draw plugs to my extension board, using this 16A socket is safe, for my extension board which can accept max 1000W?