I can easily measure the resistor on the board, now that I have the transformer removed. It's 1k.
I used my own 100R resistor. Then I get a sine wave. And about .8v RMS out for a 5A load.
If I switch to a 1k resistor, then I get the odd looking wave output again.
I used my own 100R resistor. Then I get a sine wave. And about .8v RMS out for a 5A load.
If I switch to a 1k resistor, then I get the odd looking wave output again.
Yep, both the on-board resistor (1k) and having no resistor at all gives me the odd waveform. So does a 470R. 100R works. But only gives me .8v RMS output. Not much I can do with that except read it with an ADC. I'm going to see if I can rectify a higher voltage and then clamp it to 3v with a zener diode.It acts like there is no resistor on the CT. (or a very high value)
I am using a different CT and getting a sign wave. 50 ohms and 100mV at 10A.
On a different type, 50 ohms, 1V @ 10A, seeing a good sign wave.
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