How to Measure Current in a Circuit

Video Transcript

"How do you measure current in a circuit? That is a little more tricky. To measure current, you have to connect your probes from your multimeter in series… in series being from one to the other not parallel or just connects across the top of the current path. So you put all the component for that but in series you actually have to break the connection and insert your meter into it. In the multimeter to do that I have the black here, which is the common connection COM its common to all the functions for voltage and resistance I put it in here but to do amp pres I put in one of these two connections. If I am going to measure high amps like up to 10 amps I put in this one and I can go ahead and measure coming to low I have milliamps here. My setting remains and I turn this knob so its DC I am working with so I leave it there and I look there is my amps. So I could set it to 2 milliamps, 20 milliamps and 200 milliamps, 2000 milliamps, which is the same as 2 amps. There is 10 amps and there is 2 milliamps. And that you see even 200 microamps even smaller. So we will put it on the 20 milliamps here and then to break the circuit I am going to go ahead and turn the power off first and I am going to disconnect the power from here and go ahead and insert a lead and put this connector on so I have my alligator clip. Now I will go ahead and connect my grounded probe, my negative probe to the power supply. So before what I have used to have is the power supply went directly to the circuit right here. I now broke that connection and I am inserting my meter and you can see the red from my meter goes in to the meter. Back out the black, which is this connection into here. So now I have a series flow. It is one path flowing through the meter and that is how you set it up to measure it and then you can turn it on and get your reading if you like…the light is on and I am reading 0.04 and I am set to the 10 amps scale actually here. So that is 0.04 or 40 milliamps. The resistor's even getting a little warm. You can calculate the wattage through that. "