- Joined
- Jun 21, 2013
- Messages
- 317
... I believe the power in the lights goes up by the 4th power or so of the voltage....
Power is determined by the square of the voltage.
... I believe the power in the lights goes up by the 4th power or so of the voltage....
Power is determined by the square of the voltage.
I misspoke, I was referring to life of the light bulbs, not the power, and it varies by the -16 power of the voltage, so increase in voltage is VERY detrimental to bulb life. And for some reason power below is listed as 1.6 instead of the square of voltage. I suspect that the resistance change in the bulb element as a function of temperature enters in to it.
From Wiki:
For a supply voltage V near the rated voltage of the lamp:
- Light output is approximately proportional to V [SUP]3.4[/SUP]
- Power consumption is approximately proportional to V [SUP]1.6[/SUP]
- Lifetime is approximately proportional to V [SUP]−16[/SUP]
- Color temperature is approximately proportional to V [SUP]0.42[/SUP][SUP][86][/SUP]
John Friend
Tony said it well. Here is a graphical representation of his explanation, along with a verbal one, all from http://www.phaseconverterinfo.com/phaseconverter_deltawye.htm :
View attachment 59758 "Figure 2 represents 120/240V single-phase with two voltages 180 degrees apart with neutral and ground halfway between the two voltages. The voltage measured between the two legs is 240V, and since neutral is halfway between, the voltage from either leg to neutral would be 120V."
Threads like this tend to bring out us "nit pickers" but it is all in good fun. To sum it up, household 240v is a product of a single phase of the three phases generated by the power company. That being said, the two legs of the 240 volts are are 180 degrees out of phase which, at least to me, means that they are not "in phase" .
One "nit" to pick with Tony: a 240vac circuit is 240 volts RMS and for a sine wave that is 0.707 times one side of the P-P voltage.So 240V RMS is equivalent to 339V peak or 679 V Peak to Peak.
<snip>.
One "nit" to pick with Tony: a 240vac circuit is 240 volts RMS and for a sine wave that is 0.707 times one side of the P-P voltage.So 240V RMS is equivalent to 339V peak or 679 V Peak to Peak.