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Difference between revisions of "Inverter efficiency"

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m (Charting hint)
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* The Ratio calculator would return in the required channel combination values between <tt>0..1</tt><br />To get readout values as percentage (<tt>0..100</tt>), set factor to <tt>100</tt>.
 
* The Ratio calculator would return in the required channel combination values between <tt>0..1</tt><br />To get readout values as percentage (<tt>0..100</tt>), set factor to <tt>100</tt>.
* The [[channel attributes#valid|valid range]] <tt>0..100</tt> avoid values values over 100%, which is possible by inaccurate readings.
+
* The [[channel attributes#valid|valid range]] <tt>0..100</tt> avoid values values over 100%, which is here naturally impossible but can result from inaccurate readings.
  
 
So the result will be aligned into the range.
 
So the result will be aligned into the range.

Revision as of 12:23, 28 February 2014

Abstract

By efficiency, we are really saying, what percentage of the power that goes into the inverter comes out as usable AC current (nothing is ever 100% efficient, there will always be some losses in the system).
This efficiency figure will vary according to how much power is being used at the time, with the efficiency generally being greater when more power is used. -- Solar-facts.com

The Inverter efficiency is calculated by: EfficiencyCalulation.png

Setup

For this we need the special grouping channel type: Ratio

RatioCalculatorChannel.png

  • The Ratio calculator would return in the required channel combination values between 0..1
    To get readout values as percentage (0..100), set factor to 100.
  • The valid range 0..100 avoid values values over 100%, which is here naturally impossible but can result from inaccurate readings.

So the result will be aligned into the range.

Please note:

  • The performance ratio model accepts only exact 2 sub channels for correct operation!

Channel tree

If your inverter have more than one MPP tracker (as mine), you need also another special group to sum all PDC* up.

This will be done by an Accumulator as described here.

Please mind the correct order of child channels as described above:

RatioCalculatorTree.png

Charting hint

If you want to have a more detailed result for efficiency, set the valid from attribute for example to 90.

PRChart90.png

All values below 90% are "raised" to 90%.

The efficiency (black dashed) is mostly above 96%. This shown by a fixed channel to get a feeling how the inverter peforms:

Fix96.png