question

pmano avatar image
pmano asked

PV power drops to 0 going from Absorption to float for 2+min

With full sun and a load on the inverter, the Victron MPPT 250/100 tr cuts PV power after it finishes the 2 hour absorption window and transitions to float. If I turn the MPPT 250/100 charger on/off from the app or unplug and replug the panels the power comes back at 1-2kW.

Is this normal/nominal/expected behavior ?

battleborn tech suggested I add an absorption tail current of 1.0. Which killed my Absorption cycle and went to float after 10 mins. I have removed the absorption tail current setting after testing it once, yesterday.


I have also seen the charge controller, MPPT250/100 go to 0 watts and float if I wash the panels. I have found posts talking about clouds causing the same issue.

See image for right after 1500 hours.

EDIT ****

Added today 8/27/2020, again after Abs. cycle finishes and Float starts, 4 mins MPPT ignored PV input for what reason ?

1. Is this a result of the float voltage being 27.2, so NO input is accepted from the panels until the battery bank voltage drops to 27.2? This ignores the inverter load?

I have seen the 0 input from PV, run shorter on time when I had more AC load on the inverter. Which seems to corroborate my theory, faster the battery falls from Abs. to Float voltage thresholds, faster the input from PV returns.



I do have DVCC enabled.

MPPT Controllers
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1 Answer
neoneddy avatar image
neoneddy answered ·
Is this a result of the float voltage being 27.2, so NO input is accepted from the panels until the battery bank voltage drops to 27.2? This ignores the inverter load?

I think it's exactly this.

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