question

skippeer avatar image
skippeer asked

Phoenix Smart IP43 Charger: SW bug trigger recondition / overcharging?

Have used a IP43 smart charger 12/50 (1+1) and MPPT smart regulator 100/30 several seasons with latest recommended firmwares charging AGM batteries.

Last Monday did i install LFP GBS cells and a BMS, one busbar for load and one for charging, AGM starter battery is directly connected to charge busbar.

Yesterday evening did I stop all charging while I was installing BMV-712.

Afterwards did I connect the new BMV-712 to the virtual network and restarted both solar and shore power charging.


Maybe after an hour did I notice that the starter battery voltage was 16.2 V,

BMS protected LFP cells by disconnecting them.

I expected to see 14.2 or 13.5 volt but this overcharging was a shock.

Created a user profile on IP43 to force a lower voltage.

Recondition has always been disabled.

What can trigger the 16.2 voltage?


Is it me using the Victron features in wrong way:

  • no trickle charging of any battery
  • IP43 connected to charge busbar
  • AGM starter battery connected to charge busbar
  • Service LFP bank charging conrrolled by BMS
  • via the virtual network does IP43 get voltage figures from LFP service bank from the BMV-712

Is the solution to disconnect BMV-712 from virtual network VE.smart networking

and let Shore power share data with solar regulator via virtual network?


BMV Battery MonitorchargerVE.Direct
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2 Answers
Thiemo van Engelen (Victron Energy staff) avatar image
Thiemo van Engelen (Victron Energy staff) answered ·

Hi @Skippeer

I assume that the positive of the BMV (the red wire) is directly connected to the battery, or at least in such a way that it still measures the LFP battery voltage, even when the BMS has disconnected the batteries.

What I assume happened here is that the BMS disconnected the LFP batteries but the charger(s) still received the LFP voltage via the VE.Smart network. This caused them to think that the battery voltage was only 14.2. volt, although they were actually charging the AGM battery which would continue to rise in voltage. Because there is a maximum difference between the received voltage and their own measured battery voltage of 2V, they charged upto 16.2V.

The best solution would be to connect BMS allowed to charge signals to the remote inputs of the IP43 and SmartSolar charger. This would cause them to stop charging when the BMS signals that the battery is full.

A less optimal solution would be to remove the BMV from the VE.Smart network.

As a side note: Please also look again at the settings of the BMS and the IP43 and SmartSolar charging parameters, as there should not be a need for the BMS to disconnect the batteries during regular charging (although a significant imbalance could also cause that).

Kind regards,

Thiemo van Engelen

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skippeer avatar image
skippeer answered ·

A million thanks for explaining it for me.

The BMS vendor recommends that charging of LFP cells should be managed by the BMS.

All charging to starter battery,

BMS control when charging should take place of LFP

i.e. starter batt => BMS => LFP

My first action to mitigate the IP43 ”over-charging” of the AGM starter battery was to disable VE smart networking on BMV-712, IP43 and smart MPPT.

My consumers onboard loads the service battery bank heavily, 10-15 A when sailing (2 fridges, autopilot, instruments, 2 chart plotters, VHF) so I need to charge as much as possible.

What I have read can IP43 not today sync the charging phase with Smart MPPT so I shouldn’t loose any functionality.

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