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why we multiply wattage to 1.5 ???

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manu4panjab

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hello brothers

i want to know why we mulitply wattage to 1.5 for stabilizer capacity for finding kva
like if i have a 500 watts power consumption av receiver then why i have to multiply it to 1.5
can it be just 500 watts if i have to use it with stabilizers
 
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anm

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because VA is peak, and wattage is average of volt x current over the sine curve. VA is specified for defining peak values while wattage defines avg values.
Now if an equipment defines 500 watts, the voltage or current peaks may be higher than 500VA. So you need to buy a stabilizer of higher VA rating than 500VA for a 500 watt load. If your equipment could define its rating in VA then there would not be a need to multiply by 1.5 which is also known as a power factor - it is a thumb rule avg number based on experience rather than being sn exact number.

read more details here.
Power factor - Wikipedia, the free encyclopedia
How to Convert Watts to VA and KVA to KW Simplified -- Converting Volt-amps to Watts the easy way
 

manu4panjab

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because VA is peak, and wattage is average of volt x current over the sine curve. VA is specified for defining peak values while wattage defines avg values.
Now if an equipment defines 500 watts, the voltage or current peaks may be higher than 500VA. So you need to buy a stabilizer of higher VA rating than 500VA for a 500 watt load. If your equipment could define its rating in VA then there would not be a need to multiply by 1.5 which is also known as a power factor - it is a thumb rule avg number based on experience rather than being sn exact number.

read more details here.
Power factor - Wikipedia, the free encyclopedia
How to Convert Watts to VA and KVA to KW Simplified -- Converting Volt-amps to Watts the easy way

:signthankspin: brother

one last thing please

so can i use 6amp v-gaurd stabilizer with my av receiver + projector

av receiver 500 watts + projector 300 watts

6 amp is equal to 6 x 220 = 1320 watts

500+300 = 800 x1.5 = 1200 watts

also do i need stabilizer for subwoofer too
i have 2 polkl psw 125 subs with 150 watts continous and 300 watts peak but don't know its power consumption

so how many amps stabilizer i have to use with them
 
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anm

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not sure, will leave it to other experts to answer. I think sub, amp can be kept separate from projector and music sources. Amp and sub (inbuilt amp) suck much more current and if they are on the same line as proj/ sources, they may impact video/ sources. Just a guess rather than a fact. Other experts here can comment more on this as well.

regards
 

manu4panjab

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so any suggestions guys

for 500 watts av receiver power cosumption

projector 300 watts

subwoofer total 600 watts


do i need seperate stabs for seprate source is that what you trying to say brothers
 

manu4panjab

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If you don't know the power consumption of an amp or any other piece of audio equipment, use the forumla of

power per channel x no of channels x 1.5 x 1.5

The reason for multiplying twice is that audio power amps are about 60-70% efficient, so they consume about one and a half times the amount of power they put out. The second multiplication is for the RMS to peak rating.

However I would multiply by 2, not 1.5 - this gives you headroom for future, and be aware that devices pull huge amounts of power at switch-on. If you marginalise the power stabiliser, you may have a situation when you cannot turn all your equipment on in one go :(

brother i think you don't get my questions

i mean 6amp not for 6 seprates amplifiers

i mean 6 ampier power handling of stabilizer
 

doors666

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:signthankspin: brother

one last thing please

so can i use 6amp v-gaurd stabilizer with my av receiver + projector

av receiver 500 watts + projector 300 watts

6 amp is equal to 6 x 220 = 1320 watts

500+300 = 800 x1.5 = 1200 watts

also do i need stabilizer for subwoofer too
i have 2 polkl psw 125 subs with 150 watts continous and 300 watts peak but don't know its power consumption

so how many amps stabilizer i have to use with them


It should be fine. Most of the times, you wont be using the receiver at 500W anyway. If you connect all the 7 speakers, increase the volume on all of them to the max, then its supposed to consume 500W on an average. If you are running only 5 or 2 speakers, you probably will never hit that limit.
 

manu4panjab

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It should be fine. Most of the times, you wont be using the receiver at 500W anyway. If you connect all the 7 speakers, increase the volume on all of them to the max, then its supposed to consume 500W on an average. If you are running only 5 or 2 speakers, you probably will never hit that limit.

:signthankspin: friend
i use 7.2 system
i never listen to full volume daily use is only 50% of volume

so its sufficient to go with 6amp power stabs
 

Kamal

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Alternatively,just check the power consumption figures in the manuals & multiply by 1.5/2 for a comfortable "headroom".
BUT, do you really need a stabiliser/CVT?
If you have severe voltage fluctuation probs,then OK, a cvt of an appropriate capacity can help.
If fluctuations are not an issue, then you shld be able to live with it, unless voltages dip to below 200 regularly.
E.g, today is a blisteringly hot day in Delhi so everyone has his A/C's on, voltage is 200V,which is uncommon.Normally, voltages are around 220/215 which is fine, its livable.
 

manu4panjab

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Alternatively,just check the power consumption figures in the manuals & multiply by 1.5/2 for a comfortable "headroom".
BUT, do you really need a stabiliser/CVT?
If you have severe voltage fluctuation probs,then OK, a cvt of an appropriate capacity can help.
If fluctuations are not an issue, then you shld be able to live with it, unless voltages dip to below 200 regularly.
E.g, today is a blisteringly hot day in Delhi so everyone has his A/C's on, voltage is 200V,which is uncommon.Normally, voltages are around 220/215 which is fine, its livable.

brother what if i use voltage stabilizer if fluctuation is not any issue does it harm my appliances :sad: like v-gaurd stab give use continous power of 220 volts
 

Kamal

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Manu, what I meant was that -
-If fluctuation is not an issue.
-If voltages do not drop below 200V regularly
you don't really NEED a stab/CVT.
If you still want to go ahead, then an appropriately ratedCVT with a comfortable headroom would be OK.
 

suri

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There is a problem north of the vindhyas!

Difficult to find a solution though!
 

manu4panjab

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Manu, what I meant was that -
-If fluctuation is not an issue.
-If voltages do not drop below 200V regularly
you don't really NEED a stab/CVT.
If you still want to go ahead, then an appropriately ratedCVT with a comfortable headroom would be OK.

:signthankspin: kamal
 
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