question

fortaleza avatar image
fortaleza asked

BatteryProtect for charging sources.

Hi, I have added 2 x 220A batteryprotects to my system and separated charging and loads accordingly. Alternator and inverter are not on those buses they will be switched. Charging sources are three victron mppts without remote control inputs.

During initial testing, I switched off the charging SBP via bluetooth, and off it went ok, however then there was over voltage alert and it would not switch on again until I removed the mppts from the charging input bar. Once they are not connected to the battery they show high voltages which triggers the alert and stopped the SBP from being switched back on again.

How can I fix this? What have I missed?

Elliot

MPPT Controllersbattery chargingBattery Protect
1 comment
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

jonathanv avatar image jonathanv commented ·
I am having the same issue but with an IP43 50A Phoenix Smart Charger as charge source; the BP disconnects and the charger voltage peaks to 16V+ causing the BP to go into overvoltage protection mode until I turn off the charger.


What I have noticed is that when I take the charger out of the VE network (which contains a Smart Battery Sense, the voltage does not peak to 16V+, but that's not ideal. So no solution and I am also interested in Victron's response here.
0 Likes 0 ·
2 Answers
Michelle Konzack avatar image
Michelle Konzack answered ·

The Charger AND the MPPTs should be connected on the battery side of the BatteryProtect because it is Uni-directional and can not let the current go back!


5 comments
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

jonathanv avatar image jonathanv commented ·

I know it happens often but maybe not assume that it's been wired incorrectly but instead ask it as a question? You've marked it as an answer which is a bit presumptuous.

The poster mentions he has two separate BP's, one for the loads and one for the chargers.

I've read the manual (and the 100 posts of people blowing up their BP's) and wired my charge sources to the IN side. I also have a separate BP for loads, just like the manual has for a lithium setup. This is not the source of the over voltage issue.

0 Likes 0 ·
Michelle Konzack avatar image Michelle Konzack jonathanv commented ·
The problem is here:

During initial testing, I switched off the charging SBP via bluetooth, and off it went ok, however then there was over voltage alert and it would not switch on again until I removed the mppts from the charging input bar.

...and sounds he use the BatteryProtector to cut of the MPPT from the busbar, and the MPPT, now without battery, ramped up the voltage and the BatteryProtector shutdown, because the OUTPUT of the BatteryProtector showed an Overvoltage. I have just tested it wit a spare 220A one.


I can exact reproduce the effect.

And then, WHY does someone want to install a BatteryProtector for the charging side?


It is completely useless!


0 Likes 0 ·
jonathanv avatar image jonathanv Michelle Konzack commented ·

Check the manual, it's a supported scenario to protect lithium from overchargingscreenshot-2023-05-05-134351.png

0 Likes 0 ·
screenshot-2023-05-05-134351.png (80.8 KiB)
jonathanv avatar image jonathanv Michelle Konzack commented ·

And here is Victron's solar van build guide showing the exact same setup:

https://www.youtube.com/watch?v=YW_xDerTycQ starting 3:50

And here is the diagram

https://www.victronenergy.com/upload/documents/SLD-Lucians-Victron-Van-Automotive-Solar.pdf

0 Likes 0 ·
klim8skeptic avatar image klim8skeptic ♦ jonathanv commented ·

@Jonathanv What I have noticed is that when I take the charger out of the VE network (which contains a Smart Battery Sense, the voltage does not peak to 16V+, but that's not ideal. So no solution and I am also interested in Victron's response here.

In your case you are disconnecting the battery from the charger, while the Smart Networking is trying to voltage compensate for the difference in battery voltage, and the Phoenix charger. The charger will raise its output voltage in an attempt to charge the now disconnected battery.

In both examples you have given, the BMS controls the ATC (disconnection) of the SBP. No Smart Networking involved in either example.


0 Likes 0 ·
fortaleza avatar image
fortaleza answered ·

Thanks Jonathan, glad others are seeing this not just me. I'll ignore Michael as he doesn't seem to know enough about their use.

I'm seeing +16V too at the SBP once it is cutoff from the battery. Makes sense open voltage no load. May have to use a relay type device for each mppt instead. Other wise it is a manual restart. Which is not so bad. I was going to switch it with the bmv or venus.

How does it work with lynx bmv? Maybe I need to change the mode in the app and try again.

1 comment
2 |3000
Toggle Comment visibility. Current Visibility: Viewable by all users

Up to 8 attachments (including images) can be used with a maximum of 190.8 MiB each and 286.6 MiB total.

jonathanv avatar image jonathanv commented ·

Looks like there are similar issues described here:

https://community.victronenergy.com/questions/39148/lifepo4-smart-and-battery-protect-on-the-charger-s.html?childToView=204176#answer-204176

Do you the MPPTs networked?

0 Likes 0 ·