Multimeter use how to test TRANSISTOR with Digital Multimeter
TRANSISTOR TESTING Transistor has 3 legs , namely , base collector and emitter , construction of transistor has 2 PN junction. This article will use diode concept to conduct transistor testing. NPN transistor use 2 diode concept to make it easily to understand the testing and these diode is common anode connected ( note it is not the actual equivalent circuit just for testing concept purpose) |
| HOW TO TEST TRANSISTOR |
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| NPN transistor use 2 diode to explain testing concept . |
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| NPN transistor use 2 diode , common anode , to explain testing concept |
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| NPN Transistor Symbol |
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| PNP transistor use 2 diode to explain testing concept . |
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| PNP transistor use 2 diode , common cathode , to explain testing concept . |
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| PNP transistor symbol |
Step to test transistor using digital Multimeter
( use Diode Function )
1. Find transistor leg function from its datasheet.
2. Set digital multimeter to diode test function.
3. Test B and C leg. connect test leads and test ,then switch test lead and do testing again.
Good transistor will show voltage 0.4-0.8V 1 time and show "OL" 1 time.
Bad transistor ( open ) will show "OL " 2 time.
Bad transistor ( shorted) will show "000V" 2 time.
4. Test B and E leg. connect test leads and do testing ,then switch test leads and do testing again.
Good transistor will show voltage 0.4-0.8V 1 time and show "OL" 1 time.
Bad transistor ( open ) will show "OL" 2 time.
Bad transistor ( shorted) will show "000V" 2 time.
5. Test C and E leg. connect test leads and test ,then switch test leads and test.
Good transistor will show "OL" 2 time.
Bad transistor ( shorted) will show "000V" 2 time.
Step to test transistor using digital Multimeter
( use resistance test function )
1. Find transistor leg function from its datasheet.
2. Set digital multimeter to resistance test function.
3. Test B and C leg. connect test leads and do testing ,then switch test leads and do testing.
Good transistor will show high resistance 1 time and show "OL" 1 time.
Bad transistor ( open ) will show "OL" 2 time.
Bad transistor ( shorted) will show 0 ohm 2 time.
4. Test B and E leg. connect test leads and do testing ,then switch test leads and do testing.
Good transistor will show high resistance 1 time and show "OL" 1 time.
Bad transistor ( open ) will show "OL" 2 time.
Bad transistor ( shorted) will show 0 ohm 2 time.
5. Test C and E leg. connect test leads and do testing ,then switch test leads and do testing.
Good transistor will show "OL" 2 time.
Bad transistor ( shorted) will show 0 ohm 2 time.
( use Diode Function )
1. Find transistor leg function from its datasheet.
2. Set digital multimeter to diode test function.
3. Test B and C leg. connect test leads and test ,then switch test lead and do testing again.
Good transistor will show voltage 0.4-0.8V 1 time and show "OL" 1 time.
Bad transistor ( open ) will show "OL " 2 time.
Bad transistor ( shorted) will show "000V" 2 time.
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| B-C leg testing , Good transistor will show 0.4-08V 1 time |
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| B-C leg testing , Good transistor will show "OL" 1 time. |
4. Test B and E leg. connect test leads and do testing ,then switch test leads and do testing again.
Good transistor will show voltage 0.4-0.8V 1 time and show "OL" 1 time.
Bad transistor ( open ) will show "OL" 2 time.
Bad transistor ( shorted) will show "000V" 2 time.
5. Test C and E leg. connect test leads and test ,then switch test leads and test.
Good transistor will show "OL" 2 time.
Bad transistor ( shorted) will show "000V" 2 time.
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| C-E leg testing , Good transistor will show "OL" 2 time. |
Step to test transistor using digital Multimeter
( use resistance test function )
1. Find transistor leg function from its datasheet.
2. Set digital multimeter to resistance test function.
3. Test B and C leg. connect test leads and do testing ,then switch test leads and do testing.
Good transistor will show high resistance 1 time and show "OL" 1 time.
Bad transistor ( open ) will show "OL" 2 time.
Bad transistor ( shorted) will show 0 ohm 2 time.
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| B-C leg testing , good transistor will show high resistance 1 time. |
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| B-C leg testing , good transistor will show "OL" 1 time |
4. Test B and E leg. connect test leads and do testing ,then switch test leads and do testing.
Good transistor will show high resistance 1 time and show "OL" 1 time.
Bad transistor ( open ) will show "OL" 2 time.
Bad transistor ( shorted) will show 0 ohm 2 time.
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| B-E leg testing , good transistor will show high resistance 1 time. |
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| B-E leg testing , good transistor will show "OL" 1 time |
Good transistor will show "OL" 2 time.
Bad transistor ( shorted) will show 0 ohm 2 time.
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| C-E leg testing , good transistor will show "OL" 2 time |
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| C-E leg testing , good transistor will show "OL" 2 time |
Read more of testing .
