Sorry about that @deltabert, my mistake. We are in fact sending you an emonTx.
@Gwil and @glyn.hudson, Last saterday i receved the emonTX replacement and today i installed it. This one is working perfectly. See here the output of 4 CT’s (3 on the Grid circuit, the 4th on the Solar circuit - the grid-circuit had too less slack…)
Glad this is solved, and I will return the other unit tomorrow.
@Robert.Wall - reporting back as requested : there was a solder bridge on the CT1 jack socket - between the two through-hole connections closest to the AC sensor socket.
So it had grounded the plug tip and removed the bias voltage, so presumably, the input was seeing a half-wave rectified current shifted by the software filter so that the ‘flat’ bottom half was on average equal to the top ‘rounded’ part. It clearly explains why it was reading low.
It’s the first time I’ve heard of this on a V3.