I’m working on a board based on ADE7880 that should measure voltage, currents and energy in a mono / three phase system and expose all the measure values in a web page..
For the moment I’m performing all my test using only one phase at time ( because I don’t have any three phase source available in my office ).I’m
voltage = 230Vac 50Hz
load resistive that drains about 1.8Kw
TA with 50/5 amps ratio
Rshunt = 0.25 ohm
Everything seems working well with voltages and currents. If I multiply xVRMS register for a value that depends on my input stage ( 1M/1K) I get exactly
the rms value of voltage applied. If I multiply the XIRMS registers for a value that depends on TA ratio and Shunt resistor, I get exactly the rms values
of the current.
The same for the Power: By applying the equation n 21 ( pag 44 datasheet) to the XWATT registers, I get the correct value for the active power .
But I can’t measure energy.
By reading the “billable registers” XWATTHR I was expecting to read an increasing value, but I read only a value that move up and down, around a
If I switch off the load, this value is a short number ( < 30 ). If I switch on the load, this value is something much bigger (20000.- 30000 or more)
but it increases and decreases time by time around this value. In one word, I don't see any "accumulation".
Also I’m not able to get any pulse out from CF1 output… I don’t know if these two fact are related…
I made several attemps with different values for the registers WTHR , ACCMODE , CF1DEN but with no results…
Can you give me some suggestions?
Thankyou in advance