Expert opinion request on CTSA016


Can the CTSA016 be used with an arduino to measure current in common household configuration?

CTSA Series Split Core Current Transformers.pdf (1.6 MB)

I’m checking the possibilities to measure current, kWh (and monney) for my 3d printer.

Another option is a pulsemeter like


Edit - attached datasheet to post. Moderator - BT

It can be used, but it is far from ideal. It is the type with an internal burden resistor and develops 0.333 V output. The normal Arduino runs at 5 V, which means it expects an input voltage of about 1.6 V to use the full input range. Your c.t. will use a fraction more than 20% of that.

You can improve this by setting the Arduino analogue reference voltage to a lower value. This varies from board to board (see analogReference() - Arduino Reference) and if available, the 1.0 V or 1.1 V reference will be ideal.

You will need to use a circuit like the one in our ‘Learn’ section, but you must modify the “mid-point” voltage to be the centre of the 1.1 V input range (= 0.55 V), not the centre of the 5 V supply. You do that by changing the values of R1 & R2, which will no longer be equal (R1 will be much larger than R2). You must not have the burden resistor shown on that diagram.

But are you sure you want a c.t. that will measure up to about 100 A for a 3D printer? I think you should check what current you expect. I think it will be much, much less than 100 A, and a lower current c.t. will better suit what you want to do, and give you better accuracy. The manufacturer does not specify the accuracy below 1 A, and that does not surprise me. Even at 1 A, your Arduino will have difficulty making accurate readings - the voltage you are reading is then 3.33 mV.