Quantcast
Channel: EngineerZone: Message List
Viewing all articles
Browse latest Browse all 28044

Re: ADE7880 - get negative values on xWATTHR, possive values on xVAHR using resistance load

$
0
0

Hi hmani,

 

Thank you for the help. You are right, I can get positive energy after correcting the connection. Thanks again!

 

I want to know:

 

1. In general under what the condition should I modify the content of WTHR / VARTHR / VATHR registers. In other words, can I just use the their default values or have to modify them upon the setup on my applicastion? Under the same condition, will xWATTHR / xVAHR register readings are different with different WTHR / VATHR setting?  

 

2. On the equations to calculate these values, there is one variable "n". How should I determine this variable in order to calculate WTHR / VARTHR / VATHR?

 

3. Follow AN-1171, I can find  the equation to calculate Wh/LSB for xWATTHR / xVAHR, how can I find watts/LSB to convert power register xWATT / xVA readings to the real values? Upon the data sheet, Figure 73, active power calculation, since I set voltage and current all at gain of 1. Then the peak voltage should be 500 volts, use 50 amps CT coil. Can I calculate 

 

watts / LSB = (500.0 * (50.0 * 1.414)) / 54119356d 

 

Is it right?

 

Thank you very much.

 

Karen


Viewing all articles
Browse latest Browse all 28044


<script src="https://jsc.adskeeper.com/r/s/rssing.com.1596347.js" async> </script>