SCVJeff wrote:
Gil, in the middle of everyone going round about who does and doesn't allow boost transformers, very nice write-up !
Thanks! As an EE, I'm just trying to tell it like it is.
RR24 wrote:
Harvey51 wrote:
Low voltage at a campground is kind of like a brown out, where the power company doesn't have the capacity to supply all its customers. Rather than cut some of them completely off, they allow the voltage to fall, which reduces the current draw.
When voltage drops current draw or (amps) goes up not down.
Sorry, but that is incorrect. It only goes up for AC units gut for everything else, it goes down. Ohms Law: Current = voltage divided by resistance (I=E/R).
And as I said earlier, power output of resistive device varies as the square of the voltage. If the voltage dropped to 3/4 of it's nominal/rated voltage on something like a toaster, the output will only be 3/4 x 3/4 = 9/16 of it's rating. That's why many appliances don't work well when there is a lot of voltage drop. The output of a motor
only will also vary as the square of the voltage - anything from your table saw at home to large industrial motors. AC units are different though than a motor only.
As an example, if you look at 240 volt rated heaters at a store, they are often rated for 208 volts also (a commercial/industrial voltage) and for 240 volts. At 208 volts, they put out 75% of the rating which will be shown in the heater's specs.
