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
| Is This Answer Correct ? | 1 Yes | 1 No |
Post New Answer View All Answers
What do you mean by drift velocity and mobility of a free electron?
When we trim a resistor, we are A Making a fine adjustment B Reducing its value C Increasing its value D Making a coarse adjustment
What happens to the series current , load current and zener current when the dc input voltage of a zener regulator increases?
can we calculate the voltage level for microwave energy which is using for our mobile communication?
What are schmitt triggers?
What is the importance of if in radio receiver?
Discuss the need for biasing the transistor.
What is the difference between active and passive filters?
How much losses in microwave Link?
What is meant by trc?
Compare the features of the three transistor configurations.
What are the two basic modes in which the 555 timer operates?
Give some examples of power electronics applications in the day-to-day life?
Define what is the effect of removal of bypass capacitor in a ce amplifier circuit?
how a definite tx line can acts as indefinite tx line