Introduction: Make a Rogowski Coil

What does a rogowski coil do? A rogowski coil is a usefull method of measuring the current that passes through a conductor, AC power or pulse power. A rogowski coil is a kind of current transformer, depending on the current passing through the center, the voltage output varies. This gives you usefull information on the current patterns, and if calibrated, how much current.

Electricity and magnetism are interchangable. All currents create magnetic fields. If you are looking head on to a wire, the field flows right, know as the right hand rule. Now, these magnetic field rings induce a voltage in the coil wrapped around, creating a voltage.

My coil and more info:'''''

Step 1: Parts

1) Thin guage wire, I used 30 AWG wire. Magnet is best, but i did not use magnet.
2)a coax cable that can be cut
3) a connecting coax cable
4)a microphone cord that can be cut
5) a satelite cable splitter (optional)
6).1uf ceramic capacitor
7)several million ogm resistor (You need to expierement to find a correct value)
9)Tape, or a better alternative, heatshrink
10) A laptop loaded with winscope and audacity
11) A capacitor to test the coil, I used a 400v 3900uf cap charged to 150volts.

My coil and more info:'''''

Step 2: Winding the Coil

Take the coax cable that you can cut. Cut off one end, and strip the black insulation, about 1 foot of it. I recommend pinching it with scissors, and cutting latteral. There will be a copper braid under that, cut all of it off, except a little at the end (One side of the coil connects to this). On the other side, strip the insulation very little, so some of the solid copper is showing.

Solder one end of the wire onto the solid conductor, and wind the wire while the cable is straight. It is important to get the wire tightly wound. Once you reach the other end (keep some space, about .5-1" at the end) and silder the wire to the copper braid. Wrap some tape around to make sure it stays. At this point, you can heatshrink the whole coil (reccomended), but it is not needed. Bend the end over, and lay it on the cable, into a loop. Bring the end of the coil and the beginning (Where the actual wire is) As close together as you can. Tape this in place (or heatshrink).

This picture does not show how i put it, i put it abit closer.

My coil and more info:'''''

Step 3: The Integrator

On the other end of the cable, put your capacitor in parallel (connect one end on the solid conductor, and one on the braid) From the center conductor add a resitor. From the resistor, connect it to a microphone cord, and the other wire to the braid. Your coil is complete =)

My coil and more info:'''''

Step 4: Testing

Testing before adding integration: If you choose not to have integration, do this. Connect your coil to the microphone jack, and open up winscope. Set the timescale at 10 seconds, and turn off autotrigger. Pulse a capacitor, with the anode running through the coil. If you see a spike, stop it and zoom in.

If you used the integrator shown, do this: Open winscope, and set the time scale to the lowest. Set the trigger to single, and put the cursor about 1/3rd from the left, slightly above the center. Pulse your capacitor through the coil, and see if there is a peak. If there isn't one, there can be a multitude of problems, leave a comment and i will try to help.

Keep in mind the peak direction does not matter. If yous goes down, and you want it to go up, just have the current flow the other way through the coil.

When you actually want to record an event, use audacity to record it. You can zoom in, see the pulse length, etc...
My coil and more info:'''''

Step 5: Install =)

Install and have fun =)

My coil and more info:'''''


jskaiman (author)2015-10-25

Your link to more info is broken. Can you post here?

steveastrouk (author)2012-03-13

Since its aircored, how come you get saturation ?

NachoMahma (author)2009-03-21

. Good job. A schematic and a little more theory would be nice.

raviga (author)NachoMahma2009-03-21

can do =) more theory incoming.

NachoMahma (author)raviga2009-03-21

. Thank you! That makes it much clearer.