Hi folks,

I'm looking to measure DC current in my drone's circuitry and need a reliable clamp meter that can accurately perform this task.

Has anyone here successfully used a clamp meter for this purpose? If so, could you recommend specific models available on AliExpress or other online stores that you've found to be accurate and dependable? It does not need to be expensive . A max of 20 bucks.

I know there are many options out there, but I'm particularly interested in products that have been tested by members of this community.

Thanks in advance for your help.

 

I'm looking to measure DC current in my drone's circuitry and need a reliable clamp meter that can accurately perform this task.

What is the range of currents you expect to measure?

For high currents, like car battery charging, I use a Harbor Freight Cen-Tech similar to this:


For measuring small currents, I use a Fluke 80i-110. This one is way out of your price range...

Don't let the accuracy spec for the Fluke scare you away:

I've found the +50mA to be far too pessimistic. Especially on a 50mA current.

 

Two things to know:

Most clamp meters WILL NOT measure DC current. Read carefully to be sure any meter you consider can.

The meter must be clamped around a SINGLE CONDUCTOR – i.e., around the positive OR negative conductor only.

 

If you can measure the resistance of a single wire from the battery to the ESC using a current limiter and DMM in mV then you can measure current directly with a calculation of V/R. This can be done best with a 60W digital lab supply that measures voltage, current and watts or a DIY current source to calibrate the wire's voltage drop at say 10A. Use any twisted pair to measure the voltage drop but a heavy twisted pair to inject the current across the wire in an external loop. Then you can also measure battery resistance from the load current you measure and battery voltage drop. ESR=ΔV/ΔI with two separate measurements with identical tests.

Look up Kelvin Resistance method for details to avoid end fringe effects to sense the voltage using the 4 wire method.