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What the negative and positive sign shows for power factor?
Applying a negative or positive sign to power factor is an obsolete method of describing whether it is 'leading' or 'lagging'. We no longer do this. These days, a 'leading power factor' indicates that the load is capacitive and the load current is leading the supply voltage, and a 'lagging power factor' indicates that the load is inductive, and the load current is lagging the supply voltage. Having said that, a 'negative' power factor is also the mathematical consequence of 'negative power' -i.e. the direction of power when it is fed from the load back to the supply (e.g. when the grid feeds energy into a generator, causing it to 'motor'). In this case, the power factor isn't really negative, but simply appears to be so.
Is 6.5kW greater generator than 6.5 kva generator?
Yes of cours1 kw =1.25 kva wich mean6.5 kw =8.12 kvaif you have generator 8.12 kva it give you 6.5 kw=============================Answer #2:1 kw does not necessarily = 1.25 kvaThe relationship between KW and KVA depends on the nature of the load you'repowering, and is called the "power factor". It describes how closely the voltageand current peaks coincide in time. If the load has any inductive or capacitxivereactance, then the voltage and current waveforms become separated in time.The "KVA" is the product of the full voltage and full current without regard fortheir "phase difference", but the "real" power in KW is the KVA multiplied by thecosine of the phase angle. So if there's any inductance or capacitance present,then the KW is less than the KVA. But if the load is pure resistive, then thevoltage and current on the line are in phase, the angle between them is zero,and the KW and KVA are equal.When everything is just exactly perfect, and there is no reactance on the load orthe line, then your 6.5 KVA generator can just exactly supply 6.5 KW of load, withnothing to spare. More commonly, of course, a generator with somewhat morethan 6.5 KVA capacity is required in order to supply 6.5 KW of 'real' power.
What is across the line starter?
Normally refers to a poly phase motor starter that monitors current draw in all three legs and interrupts all legs. the most popular use "heater-melting alloy" technique, magnetic current monitoring is also popular but IMHO thermal alloy offers superior protection in high starting load applications.
Is 1 kva 1 kw?
Yes, if the power factor (cosine of the phase-angle between voltage and current)is ' 1 '. In order for that to be true, the total load impedances on the line have tobe pure resistive, with zero reactance.All of this stuff applies only on an AC line. On a DC line, voltage and current arealways in phase, the power factor is 1, and KVA = KW .
Why graph between load and deflection is a straight line?
because when we r applying a certain load the deflection also increasing..))
