Mains Definition and 57 Threads

When the primary of a transformer is connected to A.C. mains, the current in it... a) is very small if the secondary circuit is open, but b) increases when the secondary circuit is closed. PLEASE EXPLAIN THESE FACTS.

hi can you tell me what should be the proper wiring for this mains variac? input 240V 50Hz Once connected, it keeps blowing up the fuse. I think it is because of the inrush current, so i want to double check with you, that i have it wired correctly. Thanx

Hi, I'm new to the forum so i don't really quite know what I'm doing yet! anyway, i know this question is REALLY basic but physics is not my forte and I'm confused... "John has just bought a new iron and sees this plate on the handle - 230V 1840W 50Hz" John irons a shirt for 10s...

The frequency of UK mains electricity is 50Hz. I know that this means there are 50 cycles per second & so it must change direction 50 times per second but a colleague is adament that this means the current reverses direction 100 times per second. I just can't get it. Can anyone explain this...

I want to make a overvoltage and undervoltage protection circuit. Overvoltage should trip at 460VAC and undervoltage at 180VAC. Any idea how to implement it.

Hi guys I'm new here and I require some help with a project I'm working on. I'm building a lamp prototype and i need to use a potentiometer to act as a dimmer. The pot needs to fit inside a 25mm ID tube, and is connected directly to the mains. First of all is this possible? I think I have found...

I just watched a video (here: http://www.putfile.com/media.php?n=Electric-Sausage) in which someone attempts to test the myth that you can cook a sausage simply by plugging it into mains electric. Have you ever made any attempt to scientifically test a silly myth, or conducted an amature...