dougrainer wrote:
myredracer wrote:
dougrainer wrote:
At 120 volts the 120 element will draw/output 300 watts of heat. At 114 it will be 285 and at 110 it will be 275. Doug
Sorry, but not quite correct. Power output of a purely resistive device (like a heater) varies as the square of the voltage (as per Ohm's law). At 114 volts it would be 270 watts and at 110 it would be 252 watts.
If really low, say at 105 volts, the output would be (105/120)x(105/120)x300 = 230 watts. Thus a fridge would be operating at 230/300 = 77% of it's nominal cooling capacity.
That's why running on low voltage can make a big difference in fridge operation - the lower it gets, the output of the 300 watt heater is exponentially worse. In that case it's better to run on propane.
Thank You, I did not know that equation. But, thanks to you, it makes the equation and power of lower voltage even MORE critical. I was taking amps times voltage to get watts, which is how I was taught. Doug
Welcome. Ohm's law - one of the most important equations I learned after 5 yrs of college, lol.
It also can have a big effect on electric space heaters, toasters, coffee makers, etc. Had trouble with our coffee maker recently due to low voltage and could only get lukewarm coffee and had to MW it. Very annoying.
