Voltage readings on an EmonTX v3 not working

Hi all.

I have an Emon TXv3 sending data (CT and temperature) properly to an nanodeRF.

But I am struggling receiving proper readings from the AC-AC adapter.

Find below what serial monitor prints:

emonTx V3 Discrete Sampling
CT 1 Calibration: 90.90
CT 2 Calibration: 90.90
CT 3 Calibration: 90.90
CT 4 Calibration: 16.60
RMS Voltage on AC-AC Adapter input is: ~159V
AC-AC adapter detected - Real Power measurements enabled
assuming powering from AC-AC adapter (jumper closed)
Vcal: 276.90
Phase Shift: 1.70
CT 4 detected
Detected 1 DS18B20..using this for temperature reading
RFM12B Initiated:
Node: 10 Freq: 868Mhz Network: 210
4837 0.00
temperature: 20.10
2008 0.00
temperature: 20.10
1951 0.00


I´m not sure if the AC-AC is faulty or what is happening.

A multimeter shows that  the voltage from the outlet is around 223V (no 159V), and the output of the AC-AC adapter s around 11V.

Thanks for your help.



Robert Wall's picture

Re: Voltage readings on an EmonTX v3 not working

Those measured voltages sound about right. Is it only the first reading from the ac adapter that is wrong, do subsequent readings by radio to your base show correct values? (You need a c.t. in CT1 to show subsequent voltage readings on the serial monitor and non-zero values when sent to the base.)

dpl's picture

Re: Voltage readings on an EmonTX v3 not working

Thanks Robert for your answer.

I was using only one c.t. in CT4, I will try later at home using CT1 and lets see whats happen.


Thanks a lot!

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