24v Nano/Madinverter


Author Message
poida

Guru

Joined: 02/02/2017
Location: Australia
Posts: 1432
Posted: 12:58am 23 Sep 2019      

0W in bottom right corner is the product of DC volts and DC current.
IF there are available values for both, and they are sensible values,
then we get a DC current value visible and a DC power value.

Offset settings are needed due to many and varied methods we can use to
feed the nanoverter it's inputs.
The analog to digital conversion requires a voltage from 0 to 5V.

I like to use LEM closed circuit control Hall effect current sensors
for DC current. These are totally isolated, need 5V supply and give output
of 0V for -50A, 2.5V for 0A and 5V for 50A
I expect the zero amp sensor output to be close to 2.5V but never exactly
what the nano sees as 2.5V
So I need to obtain zero offsets for both current sensor inputs.

I have offsets for both NTC thermistors, so I can have them both showing the same
temperature when they are exposed to the same temperature.
I could not leave it be when I saw 5 degC difference between two thermistors which
were seeing the same temperatures.

The latest code for nano2 has a display of output AC amps and AC VA
I label it as "W" but again, it's the product of AC volts and current.
It is ignorant of power factor.

latest code (AC power display):


nano2_5_ac_current_sensor_dc_signal.ino.zip
wronger than a phone book full of wrong phone numbers