Does Low “charged voltage” stop charging early?

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GSmith
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Posts: 7
Joined: Tue Jun 16, 2015 6:04 pm
My RE system: 10 Kw panels on roof. 3 X FlexMax 100, Radian inverter, 6 X Pytes V-16 LiFePo batteries, 10Kw Kubota diesel genset for backup. Off grid.
Location: Lat 23.5N Lon 109.5W

Does Low “charged voltage” stop charging early?

Post by GSmith » Thu Aug 27, 2026 1:50 pm

My FLEXnet DC “charged voltage” is set at 54V. The manual says to set this .4V below absorb voltage, 56.8V on my system. My sales/installer guy says this doesn’t matter but the manual says that the Mate3 can use the FLEXnet DC’s information to stop all charging. My system never gets above 53.5V even though the charge controllers are in ‘bulk’ mode. Is my installer correct or should I reset the “charged voltage” on the FLEXnet DC?

Any help is much appreciated,

Gerry Smith

raysun
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My RE system: (Former system. Now retired.)
Flexpower Two: (2) FXR3048A-01 - Series Stacked, (2) FM80, MATE3s, FlexNetDC
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Outback IBR3 battery enclosure
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Re: Does Low “charged voltage” stop charging early?

Post by raysun » Thu Aug 27, 2026 4:30 pm

Potentially, but not likely unless Global Charge Termination Control is enabled.
OutBack Power's Global Charge Termination Control is a system setting used via an OutBack MATE to automatically stop the absorption charging phase when connected battery parameters are fully met. It does not affect Bulk charging.
Check under Mate/Global Charge and if enabled, either disable, or if it would benefit your battery, properly set the FNDC Charged Voltage, Charged Time, and Charged Return Amps.
The latter you may wish to do in any event so the battery state of charge reading is more accurate.

Regarding not fully charging the battery:

Are the FlexMax 100 set up with Remote Voltage Sense wiring providing accurate battery voltage data?
Does the inverter/charger fully charge the battery when on generator power?

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