question

I may have figured it out? I just read this post, copied and pasted below, from a contributor from 2021 similar problem with a 12v charger. I also enabled VE Network on the chargers just prior to noticing the issue.

IP22 Charger charging at 16v+

Morning, I have a IP22 charger connected to a 120AGM battery along with a BMV-712. I had the charger set to 14.7 volts. When monitoring the charger etc it showed what I expected. I then enabled V.E Smart on the BMV and joined the IP22 to the network. It is sharing amps and volts. What I noticed is the charging went over 16v+ (disable VE and it goes back to 14.7). My Battery Protect said over voltage and disabled its output. The Voltage on the IP22 and Battery Protect said 16v+, but the BMV said it was 12.9 (ish). The SOC on the BMC was 100%, but i decided to resync it and then the voltages all dropped back to 14.7 and has been fine since. So my question is what happened as the IP22 shouldn't go above 15v (with the high setting)? Just a bit worried that it will happen again and potentially damage something. Cheers in advance :)

To charge up a battery the voltage potential of the charge source has to be higher than destination. Otherwise how does it raise the voltage?

Adding amps will not change voltage.

There would be a problem if the battery then ended at the voltage of 30V (and so was overcharged) and you didn't want that. Did this happen? If not there is no problem here.

The other possible reason for voltage difference is voltage drop over cable due to high resistance connections. Something the bmv is suppsed to help compensate for in a smart network.

Then there is also temperature compensated charging which also alters end charge voltage.

I understand there has to be a higher potential in order to charge the batteries.

The boat’s electrical cabinet has an analog gauge for each bank of batteries and I’ve never seen it exceed 29v until I installed the IP22 chargers.

When I turned on the ignition switches today to start the engines, while the chargers were still on, I got over voltage alarms from the engine electronics.

I went back to the boat this evening and disconnected the charger from the VE network and the voltage immediately dropped back to 28.6v. So it appears there is some issue with the chargers when connected to the network. FYI I also have a BMV 712 and an MPPT

Hi @Mark Callinan

Where is your BMV connected to? You say you have two battery banks, but there is only 1 BMV.

FYI: All the devices in a single VE.Smart network should be connected to the same battery and there should be no other devices in that network. So when you have two chargers connected to two separate battery banks you should create a separate VE.Smart networks for each of the chargers. When the batteries are connected in parallel, there they effectively form one battery bank and they can be in the same network, (but using two chargers is also not really needed). But when the BMV is connected for example to the house bank, it should not be in the same network.

Kind regards,

Thiemo van Engelen

Hi @Thiemo van Engelen (Victron Energy staff)

The BMV is connected to the house batteries.

I effectively have 3 battery banks. House, Port Start & Starboard Start.

I realised after purchasing the 2 x battery chargers & then researching on this forum how the 3 outputs on each charger works, as it's not explained in any of the sales literature, that I could have done it with one.

I now have another issue. After taking the boat for a run and returning to the berth and reconnecting to shore power the Starboard charger would not turn on? I suspected it may be an over temperature protection issue as the engine room temp was high, but that doesn't explain why the Port charger was still working as they are mounted side by side? I will go back this evening and check it, now that it would have cooled down.