Feeder and service load calculation requirements can be found in Part III of Art. 220 in the 2014 NEC. As noted in Sec. 220.52(B), "A load of not less than 1,500VA ...

When a circuit is pushed past its limits, it rarely fails politely. It signals trouble through tripped breakers, hot outlets, ...

In Part 1, we looked at how to size a branch circuit and walked through a simple example. So if you’re sizing a feeder, why don’t you do it the same way? Except in cases where a feeder is also ...

The simplest model of a battery comprises an ideal voltage source that connects in series with a resistance whose value—often a few milliohms—depends on the battery’s electrochemical condition and ...

Suppose that you need to test a 1.5V, AA-size alkaline battery. You can apply a short circuit and measure current, or you can measure open-circuit voltage, but neither method properly tests the ...

This article is part of the Ideas for Design Series: Vol. 3, No. 8. This circuit builds on a previous idea in which the addition of an optocoupler to a microcontroller output converted a “dumb” ...