Hi,
I am trying to measure the current of my circuit.
After adding the currents of each components together, the whole current is: 120mA
The below image is the measurement that I have done with multimeter, which is: 13.5mA
Why there is a huge difference between these two numbers?
More info:
Same result (13.5) with another multimeter has shown.
If I change that rotatory-thing in the middle to "20m", the circuit would have some unusual activities.
Thanks
Are ALL measurements made with STEADY STATE currents? That means none are digital.
Paul
Yes
You are using the meter(s) wrong, or your image is wrong.
If your picture is accurate your meter is connected wrong... The black lead goes to "COM".
Yes, you need to review how to properly connect your DVM to measure current !
Also, when measuring digital load currents with dynamic signals, you will be measuring average current, not peak.
Short duration digital signals may not seen at all.
BTW
Battery consumption is bad for your heath ;).
Thanks everyone, I appreciate your inputs.
To make sure I am on the right path, I decided to measure the current of a 5mm LED and the result is: ~170
Is it right?
Edit: I am using the same technique as shown in the first post.
What is your circuit? How you got the 120 mA figure? Your DMM likely works well.
Always back up what you are saying with:
Show us a good schematic of your circuit.
Show us a good image of your ‘actual’ wiring.
larryd:
Always back up what you are saying with:Show us a good schematic of your circuit.
Show us a good image of your ‘actual’ wiring.
I am using the same technique as shown in the first post, sorry if I was not more clear.
So you are connecting your DMM Incorrectly, as in your post, and you get 170 'things' (I assume mA) - does this look correct based on the resistor and LED Datasheet.
PS 170 mA looks wrong.
maatthew:
I am using the same technique as shown in the first post, sorry if I was not more clear.
Please show the ‘actual’ image showing this measurement.
The black lead needs to go to the COM.
In this image:
Which one of the multimeters is correct?
Left Multimeter needs red lead in mA connector.
Now you do know that LED needs a series dropping resistor ?
Great, now we need to know how you have that LED wired, what size of series resistor you have, or if it is a 'resistor less' LED (if it is we need the datasheet).
180mA is HUGH for an LED - I run them at around 5mA
