amps kill!

[LarryFine]

Why then isn't the current increasing with the increased voltage as you previously in another post brought to my attention in another post?

Because you have to decide whether "increased voltage" means voltage rising with no equipment adjustments, or using a higher nominal voltage with equipment differences.

If the former, the current goes up; if the latter, the current goes down. By the way, the utility won't see any difference between supplying a given amount of KW's of 120v loads and the same KW's of 240v loads.

Power companies can and often do add capacity to a primary line by raising the voltage supplied to it. They also have to replace the transformers (unless it has taps within the range) to match the new higher primary voltage.

Those new transformers will have a larger primary impedance, which is how the voltage can increase without increasing the current: the resistance has increased. They could also use the same trick to decrease current if supplying a load that is not rising.

Remember about separating the variables from the constants. Also, remember that re-building a load for a different voltage gives you a new constant, i.e., a new resistor.

 

[steelersman]

Because you have to decide whether "increased voltage" means voltage rising with no equipment adjustments, or using a higher nominal voltage with equipment differences.

If the former, the current goes up; if the latter, the current goes down. By the way, the utility won't see any difference between supplying a given amount of KW's of 120v loads and the same KW's of 240v loads.

Power companies can and often do add capacity to a primary line by raising the voltage supplied to it. They also have to replace the transformers (unless it has taps within the range) to match the new higher primary voltage.

Those new transformers will have a larger primary impedance, which is how the voltage can increase without increasing the current: the resistance has increased. They could also use the same trick to decrease current if supplying a load that is not rising.

Remember about separating the variables from the constants. Also, remember that re-building a load for a different voltage gives you a new constant, i.e., a new resistor.

Larry thanks for all of these explanations to my questions about this topic. I greatly appreciate it. I have a much better understanding now of all this electrical theory. Just so you know I've always understood P= EI and that you don't use less Watts by supplying a higher voltage. I just had never really taken into my head and thought about it before the equation: R=E/I. You're posts are an exellent read. Don't forget: Amps kill!!

 

[bill@usps06492]

A good book on this subject is "Overcurrents and Undercurrents", its about gfci's, afci's, and electrical safety. It's written by Earl Roberts who was a designer of these units.

Also according to Senior Chief Biez, EMCS, USN E-Div USS Detriot AOE4, 1976-80, would drill into our heads his safety mantra, "It takes less than 1/10th of an amp to stop your heart! So shut off the #@%$$&* POWER!!! AND MAKE SURE IT'S OFF! TEST IT BEFORE YOU STICK YOUR #%$&**# HANDS IN THERE!!!

Along with a few other of his favorite slogans such as, Get a #@%$$# haircut or I'll pull your #%$$# liberty card. How many times do I have to tell you #@%$& guys, Lefty Loosey and Rightys Tightsy"
Bill USPS06492