Tutorial 1. Why does the voltage drops to 0?

Hi,

In the first tutorial "Simulate an LED and Resistor" after the circuit is completed and I check the voltage after the LED it shows that the Direct current voltage is zero (0). Why is that? Why there is no voltage in the circuit at that point?

by AbdulRahim_Electronics
August 29, 2021

Many possibilities. You may have an error because the loop is not completed. When that happens, you should have an error message when you try to run the simulation. Sometimes you can detect such "connection fault" by dragging a component (the source, the resistor, or the LED, here) and if really connected, the "wires" will follow. If they don't, you have the faulty wiring. Try to reinsert the faulty wire.

Now, when you speak of "the current voltage is zero", you mean "the actual voltage is zero"? A VOLTAGE, in volt or milli-volt, is not a CURRENT, in ampere, or milliamp. A wire, in an uncompleted loop, but with the wire connected to the + side of a dc source will have a voltage equal to the voltage of the source but would have no current passing through it (if we neglect thermal effects).

by vanderghast
August 30, 2021
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