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How does my MPPT controller know when to stop Absorption during Grid Support or Sellback?

Issue:
The Absorption cycle when the MPPT is pushing power to compensate for the loads seems longer than usual.

Product Line:
MPPT60, MPPT80

Environment:
Generally, on-grid MPPT charge controller.  This can happen off-grid if the load demand is high enough.

Resolution:
There is an algorithm being processed in the background to calculate the when the MPPT controller should exit Absorption and transition to float.  The math is based on three parameters and their tolerances so the Absorb time may sometimes last a little longer than normal or until the Absorb Time setting is reached.  When the Conext Battery Monitor is installed, this calculation a more accurate.

Cause:
There are 2 methods for the MPPTs to exit Absorption.  The first, is when the charging current reaches 2% of the set capacity.  The other, is when the Absorb Timer is reached.  When the XW+ units are selling back to the grid, the MPPTs are generally producing a higher amount of current.  Due to the high current while selling, it is not clear whether the MPPTs are calculating the exit current or if it only uses the Absorb Time.
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