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MarkU
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user3073
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Perhaps a Simple Question, but maybe Im misunderstanding "Voltage" drop in terms of LEDS.

So I have a Circuit wired up with a 9V Battery, one 270ohm Resistor and 3 Blue LEDS (that draw around....20ma and 2.0v forward voltage. (this is for testing purposes, I would always put a resistor with each LED)

I put in 1 Led and Read the Ground and Positive Leg of the LED. Multimeter says: 3.52 V ok.....

2 Leds (same LED): 3.35v

3 Leds : 3.20v

enter image description here

It's hard to see on my super crude MS paint, but im labeling each LED with what the Voltage on the Multimeter reads when I measure that LED leg.

Whats going on here? the LEDS get slightly dimmer (and I mean VERY slight).....but shouldn't the voltage difference after each one be alot more?

Also the Entire System is drawing 30mA exactly (+/- .2-3 mA) regardless of How many LEDS I have on there(and im checking the mA after each additional LED leg to be sure). Clearly im missing something? Is this because the LEDS are in Series? I just kinda assume "Ok more LEDS = MORE mA drawn and voltage drops among each LED.

And I know theirs a Similar question about LEDS in Series, but im more curious about WHY there is no voltage drop or mA change per LED in Series than if it's a good or bad idea (Im sure it's not a great idea to keep LED in series like that of course).

Perhaps a Simple Question, but maybe Im misunderstanding "Voltage" drop in terms of LEDS.

So I have a Circuit wired up with a 9V Battery, one 270ohm Resistor and 3 Blue LEDS (that draw around....20ma and 2.0v forward voltage. (this is for testing purposes, I would always put a resistor with each LED)

I put in 1 Led and Read the Ground and Positive Leg of the LED. Multimeter says: 3.52 V ok.....

2 Leds (same LED): 3.35v

3 Leds : 3.20v

Whats going on here? the LEDS get slightly dimmer (and I mean VERY slight).....but shouldn't the voltage difference after each one be alot more?

Also the Entire System is drawing 30mA exactly (+/- .2-3 mA) regardless of How many LEDS I have on there(and im checking the mA after each additional LED leg to be sure). Clearly im missing something? Is this because the LEDS are in Series? I just kinda assume "Ok more LEDS = MORE mA drawn and voltage drops among each LED.

And I know theirs a Similar question about LEDS in Series, but im more curious about WHY there is no voltage drop or mA change per LED in Series than if it's a good or bad idea (Im sure it's not a great idea to keep LED in series like that of course).

Perhaps a Simple Question, but maybe Im misunderstanding "Voltage" drop in terms of LEDS.

So I have a Circuit wired up with a 9V Battery, one 270ohm Resistor and 3 Blue LEDS (that draw around....20ma and 2.0v forward voltage. (this is for testing purposes, I would always put a resistor with each LED)

I put in 1 Led and Read the Ground and Positive Leg of the LED. Multimeter says: 3.52 V ok.....

2 Leds (same LED): 3.35v

3 Leds : 3.20v

enter image description here

It's hard to see on my super crude MS paint, but im labeling each LED with what the Voltage on the Multimeter reads when I measure that LED leg.

Whats going on here? the LEDS get slightly dimmer (and I mean VERY slight).....but shouldn't the voltage difference after each one be alot more?

Also the Entire System is drawing 30mA exactly (+/- .2-3 mA) regardless of How many LEDS I have on there(and im checking the mA after each additional LED leg to be sure). Clearly im missing something? Is this because the LEDS are in Series? I just kinda assume "Ok more LEDS = MORE mA drawn and voltage drops among each LED.

And I know theirs a Similar question about LEDS in Series, but im more curious about WHY there is no voltage drop or mA change per LED in Series than if it's a good or bad idea (Im sure it's not a great idea to keep LED in series like that of course).

edited body
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user3073
user3073

Perhaps a Simple Question, but maybe Im misunderstanding "Voltage" drop in terms of LEDS.

So I have a Circuit wired up with a 9V Battery, one 270ohm Resistor and 53 Blue LEDS (that draw around....20ma and 2.0v forward voltage. (this is for testing purposes, I would always put a resistor with each LED)

I put in 1 Led and Read the Ground and Positive Leg of the LED. Multimeter says: 3.52 V ok.....

2 Leds (same LED): 3.35v

3 Leds : 3.20v

Whats going on here? the LEDS get slightly dimmer (and I mean VERY slight).....but shouldn't the voltage difference after each one be alot more?

Also the Entire System is drawing 30mA exactly (+/- .2-3 mA) regardless of How many LEDS I have on there(and im checking the mA after each additional LED leg to be sure). Clearly im missing something? Is this because the LEDS are in Series? I just kinda assume "Ok more LEDS = MORE mA drawn and voltage drops among each LED.

And I know theirs a Similar question about LEDS in Series, but im more curious about WHY there is no voltage drop or mA change per LED in Series than if it's a good or bad idea (Im sure it's not a great idea to keep LED in series like that of course).

Perhaps a Simple Question, but maybe Im misunderstanding "Voltage" drop in terms of LEDS.

So I have a Circuit wired up with a 9V Battery, one 270ohm Resistor and 5 Blue LEDS (that draw around....20ma and 2.0v forward voltage. (this is for testing purposes, I would always put a resistor with each LED)

I put in 1 Led and Read the Ground and Positive Leg of the LED. Multimeter says: 3.52 V ok.....

2 Leds (same LED): 3.35v

3 Leds : 3.20v

Whats going on here? the LEDS get slightly dimmer (and I mean VERY slight).....but shouldn't the voltage difference after each one be alot more?

Also the Entire System is drawing 30mA exactly (+/- .2-3 mA) regardless of How many LEDS I have on there(and im checking the mA after each additional LED leg to be sure). Clearly im missing something? Is this because the LEDS are in Series? I just kinda assume "Ok more LEDS = MORE mA drawn and voltage drops among each LED.

And I know theirs a Similar question about LEDS in Series, but im more curious about WHY there is no voltage drop or mA change per LED in Series than if it's a good or bad idea (Im sure it's not a great idea to keep LED in series like that of course).

Perhaps a Simple Question, but maybe Im misunderstanding "Voltage" drop in terms of LEDS.

So I have a Circuit wired up with a 9V Battery, one 270ohm Resistor and 3 Blue LEDS (that draw around....20ma and 2.0v forward voltage. (this is for testing purposes, I would always put a resistor with each LED)

I put in 1 Led and Read the Ground and Positive Leg of the LED. Multimeter says: 3.52 V ok.....

2 Leds (same LED): 3.35v

3 Leds : 3.20v

Whats going on here? the LEDS get slightly dimmer (and I mean VERY slight).....but shouldn't the voltage difference after each one be alot more?

Also the Entire System is drawing 30mA exactly (+/- .2-3 mA) regardless of How many LEDS I have on there(and im checking the mA after each additional LED leg to be sure). Clearly im missing something? Is this because the LEDS are in Series? I just kinda assume "Ok more LEDS = MORE mA drawn and voltage drops among each LED.

And I know theirs a Similar question about LEDS in Series, but im more curious about WHY there is no voltage drop or mA change per LED in Series than if it's a good or bad idea (Im sure it's not a great idea to keep LED in series like that of course).

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user3073
user3073