emonPi2 initial setup

Tank · 2023-12-29T12:15:01.208Z

Hello,
Finally got round to putting my emonPi2 in place…
Just setup with 2 x 100A clamps in 1 and 2 and the emonVs.
Comparing the readings with my smart meter…the grid consumption is roughly 1000w from my meter and 3000w from the emonPi.
Setup is as follows
Settings:
Band 433 MHz, Group 210, Node 27, 7 dBm
Calibration:
vCal = 101.30
iCal1 = 300.30
iLead1 = 3.20
iCal2 = 300.30
iLead2 = 3.20
iCal3 = 150.15
iLead3 = 3.20
iCal4 = 150.15
iLead4 = 3.20
iCal5 = 150.15
iLead5 = 3.20
iCal6 = 150.15
iLead6 = 3.20
datalog = 9.80
pulses = 1
pulse period = 100
RF off
JSON Format Off
Here is one line of output
MSG:181,V1:245.21,P1:2867,P2:245,P3:0,P4:0,P5:0,P6:0,E1:1399,E2:224,E3:-39,E4:-33,E5:-10,E6:0,analog:2096
The second input is reading my solar production and is also a lot out.
Any ideas as to why it is so far out?

Robert.Wall · 2023-12-29T12:42:15.174Z

Maybe because you’ve told it you have 300 A c.t’s on inputs 1 & 2, and 150 A c.t’s on the remainder?

I suggest you read the documentation for emonLibDB. All this is fully documented, along with example sketches, in the emonLibDB library zip download: EmonLibDB - Version 1.0.2

Tank · 2023-12-29T12:48:44.465Z

@Robert.Wall Thanks for the reply,
I set up the values from the serial config page on the emonPi2…
If they are incorrect then maybe that setup page is sending the wrong values ?

Robert.Wall · 2023-12-29T13:13:26.933Z

You might be correct, I haven’t seen the emonPi2, so I don’t know what’s inside it. I wrote the library, I’ve no control over how it is used.

Somewhere, you should have the ability to edit the ‘front end’ (i.e, the ‘emonTx4’ part) sketch with the correct configuration and compile and upload it, assuming (maybe without good reason) it’s like the original emonPi.

[Edit]
If you can’t do this, then in emonCMS, you need to divide the voltages by 1.013, the currents by 3.003 and the powers by the product of those, to get closer to the correct results. Page 3 of the documentation “EmonLibDB Application Interface - Power & Energy” gives details of the calibration constants. These haven’t changed since the first release of the library in May.

Tank · 2023-12-29T14:52:14.046Z

@Robert.Wall Thanks
I have done it by entering the k values in the serial send box on the serial config page.
Thanks for your help…

Robert.Wall · 2023-12-29T15:22:52.816Z

@Tank
It would appear you missed the settings at the top of the page. You needed to set the Voltage calibration to exactly 100, for the Firmware version select emonLibDB, finally choose the c.t. rating for the inputs(s) in use.

Screenshot 2023-12-29 15:16:251103×339 26.9 KB