What are the different ways to check LED light/bulb?

Answer Posted / chary

1. LED polarity can be checked by observing the terminals
usually longer lead is positive.
2. LED can be tested by Multimeter (digital or Analogue)
DMM should be kept in diode test mode by observing the
polarity .
meter indicates the drop ( !V to 2.7 V) depending on LED
colour . whem terminals are reversed should not indicate.
this confrms LED is good
3.When using analog multimeter keep range selector in
lowest Resistance range . in analog multimeters in
resistance mode the -ve or black wire should be treated as
+ve lead
4. LED can also be tested by connecting it to a 3v Battery /
AC adapter with a resistor(1K to 10K )connected in series

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