On diode check what does a shorted diode voltage will measur

On diode check, what does a shorted diode voltage will measure? Justify your answer?

Solution

The key function of an ideal diode is to control the direction of current-flow. Current passing through a diode can only go in one direction, called the forward direction. Current trying to flow the reverse direction is blocked. They’re like the one-way valve of electronics.

If the voltage across a diode is negative, no current can flow*, and the ideal diode looks like an open circuit. In such a situation, the diode is said to be off or reverse biased.

As long as the voltage across the diode isn’t negative, it’ll “turn on” and conduct current. Ideally, a diode would act like a short circuit (0V across it) if it was conducting current. When a diode is conducting current it’s forward biased(electronics jargon for “on”. Hence the short voltage of the diode measured should be 0Volts.