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Large negative energy spike SCT-019

Hi all, I have an SCT-019 CT connected to one of my EmonTX units, which is monitoring a typically >100Amp load from farm supply (from electricity supplier - single phase). I have adjusted the burden resistor accordingly and modified the sketch to suit the sct-019. Works OK for the most part, but do regularly (while on higher loads >100A) get the strange negative spikes. Do these look OK? and could they be explained?

Exact details please. The negative spikes go suspiciously close to -32767, which suggests to me that you’ve got the scaling wrong and you’re seeing an integer overflow.

[That suggests you have the SCT-019-000 - is that correct?]

Only you know if you can return 30,000 of whatever the unit is to the supply.