Naomba msaada kilowatts 2.5 ni sawa na kva ngapi? | JamiiForums | The Home of Great Thinkers

# Naomba msaada kilowatts 2.5 ni sawa na kva ngapi?

Discussion in 'Tech, Gadgets & Science Forum' started by mgange hussein, Oct 18, 2012.

1. ### mgange husseinSenior Member

#1
Oct 18, 2012
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Nataka kununua generator,vitu ninavyotumia nyumbani jumla ni kilowatts 2.5 sasa nichukue generator ya kva ngapi.Nataka generator ndogo ya wastani itakayofanana na uwezo wa vitu vyangu.Pia naomba kujua maana ya KVA.

2. ### mathcomJF-Expert Member

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Oct 19, 2012
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KVA = kilo volts ampere. Hazina tofauti sana na KW kama unatumia 2.5 KW nunua generator ya 2.5 kVa

3. ### JarambaMember

#3
Oct 19, 2012
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Ki uhandisi zaidi iko namna hii,
KVA = Kilo Voltage Ampere
KW = Kilo Watt
Watt= Voltage (V) * Ampere (A) i.e W= VA

Kwa ufupi KVA ni sawa na KW ni namna ya rating tu ila kitu kile kile.
Kama matumizi yako ni 2.5 KW ni vizuri ukanunua generator yenye ukubwa zaidi ya 2.5 KVA kwa sababu ya matumizi ya baadae yanaweza kuongezeka so ni vzr uka-focus future usage pia.

4. W

### WanzukiSenior Member

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Oct 19, 2012
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Ni sawa KVA = Kilo Volt-Ampere, lakini sio sawa na KW (KiloWatts). Kwa machine kama generator (ina resistors, capacitors na inductors), KVA rating yake sio sawa na KW. Katika hali kama hii KVA huwa ni kubwa kidogo kuliko KW. Inabidi KW kugawanya na factor fulani (power factor) ili kupata KVA.
KVA = KW/Power Factor
Kwa kesi yako, KVA = 2.5/Power factor. Hii power factor inategemea tofauti ya 'phase' kati ya current na voltage kwa system husika. Kwa kukadiria huwa inatumika 0.8

Hivyo, utapata: Generator yako iwe angalau 2.5/0.8 = 3.1 KVA. Hivyo ni vizuri ukanunua generator ya kati ya 3.2 - 3.5KVA itakufaa.

5. ### mujunguSenior Member

#5
Oct 19, 2012
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mkuu hesabu za 3.5kva zimetulia.

6. ### Kaka'JF-Expert Member

#6
Oct 19, 2012
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Alichosema wanzuki ni sahihi.
Tecnically katika umeme kuna kitu kinaitwa load. katika umeme load ni kifaa chochote katika mfumo wa umeme ambacho hubadili umeme kwa maana volts na amperes tunazoozijua kwenda katika nishati fulani i.e mwanga, mekanika, sauti n.k.

1. resistive
2. inductive
3. capacitive.

katika mfumo wa umeme wa D.C unaweza ukasema directly kwamba kizio cha watts ni sawa na kizio cha volt-ampere. Ila katika mfumo wa umeme wa A.C haiko hivyo kwani hizi loads za aina mbili i.e (inductive na capacitive) huwa zinaathiriwa na mfumo huu kwani volt na ampere huwa vinakuwa havipo katika phase moja kwa maana either voltage inai-lead current ama vice versa. Hivyo basi kwa mfumo huu wa AC kuna kitu kinaitwa power factor(P.F) ambapo unaweza sema kwamba power factor ni ratio ya real power inayoenda katika load na apparent power inayozunguka katika mfumo huo wa umeme na kimahesabu

P.F = cos (angle difference btw V and A)
KVA * Power Factor = KW

Ni ngumu sana na practically hakuna electrical system ambayo total load yake ni pure resistive. Na commonly power factor huchukuliwa kama 0.8 kwa system za kawaida, 2.5Kw/0.8 = 3.1Kva Hivyo basi kwa mahitaji yako kama alivyosema wanzuki utahitaji jenereta ya 3.1Kva mpaka 3.5Kva

7. ### KirakaJF-Expert Member

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Oct 19, 2012
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8. ### Faru KabulaJF-Expert Member

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Oct 19, 2012
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Yeah, you went to study, not only to read. You're right

9. ### Kaka'JF-Expert Member

#9
Oct 19, 2012
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Alichosema wanzuki ni sahihi.
Tecnically katika umeme kuna kitu kinaitwa load. katika umeme load ni kifaa chochote katika mfumo wa umeme ambacho hubadili umeme kwa maana volts na amperes tunazoozijua kwenda katika nishati fulani i.e mwanga, mekanika, sauti n.k.

1. resistive
2. inductive
3. capacitive.

katika mfumo wa umeme wa D.C unaweza ukasema directly kwamba kizio cha watts ni sawa na kizio cha volt-ampere. Ila katika mfumo wa umeme wa A.C haiko hivyo kwani hizi loads za aina mbili i.e (inductive na capacitive) huwa zinaathiriwa na mfumo huu kwani volt na ampere huwa vinakuwa havipo katika phase moja kwa maana either voltage inai-lead current ama vice versa. Hivyo basi kwa mfumo huu wa AC kuna kitu kinaitwa power factor(P.F) ambapo unaweza sema kwamba power factor ni ratio ya real power inayoenda katika load na apparent power inayozunguka katika mfumo huo wa umeme na kimahesabu

P.F = cos (angle difference btw V and A)
KVA * Power Factor = KW

Ni ngumu sana na practically hakuna electrical system ambayo total load yake ni pure resistive. Na commonly power factor huchukuliwa kama 0.8 kwa system za kawaida, 2.5Kw/0.8 = 3.1Kva Hivyo basi kwa mahitaji yako kama alivyosema wanzuki utahitaji jenereta ya 3.1Kva mpaka 3.5Kva

10. ### MrimiJF-Expert Member

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Oct 19, 2012
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Naam, hii ndiyo Jamii Forum bwana!

11. ### Capt TamarJF-Expert Member

#11
Oct 19, 2012
Joined: Dec 15, 2011
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