Mystery charger performance ?

[Hillhater]

Can anybody explain whatis happening with a dc/ dc charger being used in an RV to charge a 12 v LifePo aux battery.
It is a Victron Orion tr smart 121230 unit that reads an input voltage of 13.5v, an output voltage of 14.5 v, whilst connected to the discharged LiFe batt ( reading 11.5 v)
but no charge current flows ?
The blutooth data says it is in “Accumulation mode” (constant current ?), when it should be in ”Bulk charge mode” ( max current = 30amps).
I am struggling to understand how a charger can have a 3.0v voltage differential to thebattery, but not provede a charge current ?
..so are several auto techs, and Victron support !,
any suggestionorcomments welcome….before i buy a alternative unit. !

 

[fechter]

Does the battery have a BMS?
Sounds like there's a disconnect between the 14.5v output and the 11.5v battery. Using a voltmeter, you should be able to trace down where the disconnect is.

 

[E-HP]

Does the battery have a BMS?
Sounds like there's a disconnect between the 14.5v output and the 11.5v battery. Using a voltmeter, you should be able to trace down where the disconnect is.

Just thinking out loud to understand how this stuff works, but if the charge FETs in the BMS disconnect, does that result in a floating ground with respect to measuring voltage at the charging terminals? Would measuring the cell level voltages provide any useful into?

 

[fechter]

Most bms units disconnect on the negative side and the positive side is always connected.

If the bms is tripped the voltage measurement on the terminals could be way off.

Measuring the cells may be useful.

 

[Hillhater]

Thanks for the thoughts.
..yes, the LifePo battery does have a bms,.. but using a different charger (Turnegy Reactor ) from the same 13.5v source, i can charge the battery normally at 15+ amps via the same terminals.
It will also charge normally from a mains power charger …Only the Victron gives the problem….?

 

[jonyjoe303]

are all the wiring for the engine shutdown detection correctly wired up? You can try and do the manual engine shutdown override, to see if you get power to the aux battery.
I notice in the manual if the wiring isn't properly connected to detect if the engine is running, no current will flow.

 

[Hillhater]

are all the wiring for the engine shutdown detection correctly wired up? You can try and do the manual engine shutdown override, to see if you get power to the aux battery.
I notice in the manual if the wiring isn't properly connected to detect if the engine is running, no current will flow.

I am using the auto detect option with the jumper connection as suggested.
The unit does switch off ( app display says ..” No working , Engine stopped”), when the engine is stopped and operates when the engine starts indicating the 14.5 v output… but no charge current !

 

[E-HP]

Thanks for the thoughts.
..yes, the LifePo battery does have a bms,.. but using a different charger (Turnegy Reactor ) from the same 13.5v source, i can charge the battery normally at 15+ amps via the same terminals.
It will also charge normally from a mains power charger …Only the Victron gives the problem….?

Any chance of either a damaged conductor or poor connection on the charger output (terminals screwed down tight) or a poor/broken solder connection internally? Reminds me of when a have a poor connection on my car battery. There's voltage, and can even turn on the interior lights, but when attempting any significant amount of current, then nothing.