Synchronizing Victron Components

[CPT Davenport]

Simply put, my Victron charge controller goes into float mode when smart shunt only reads 95%. Even when there is plenty of solar available to get me to 100%. Shunt is set for lithium and 100% is set at 14.4v. If shunt is set at 14.4 max, should I set float at 14.4 on CC?

 

[Vic Harder]

short answer, yes. All your components should be set to the same values, which may not be the defaults. Which Victron components do you have?

 

[CPT Davenport]

Thanks Vic.

Victron components are:

MPPT 100V 20 amp BT Charge controller
500 amp smart shunt


Battery: 206ah SOK lithium
Solar: 175w (roof mount) 135w (auxiliary folding panel)

 

[Charlie]

Simply put, my Victron charge controller goes into float mode when smart shunt only reads 95%. Even when there is plenty of solar available to get me to 100%. Shunt is set for lithium and 100% is set at 14.4v. If shunt is set at 14.4 max, should I set float at 14.4 on CC?

Maybe I'm missing something here. My Victron shunt determines state-of-charge (SOC) based on amp-hour usage, compared to the battery ampacity that I specify. It doesn't use voltage as a measure of the SOC.

I don't think that the MPPT uses the SOC from the shunt to control the charge profile; I'm pretty sure that it guesses it from battery voltage. I recall bumping up the absorption voltage by a few tenths V on my MPPT in order to get it to put a little more charge into the battery. Unfortunately I can't look at my system right now to see my settings.

 

[CPT Davenport]

So Should I set the absorption on my CC to the same number as the 100% SOC on my shunt? 14.4v in this case.

 

[Vic Harder]

So Should I set the absorption on my CC to the same number as the 100% SOC on my shunt? 14.4v in this case.

Yes. I'll try and get pics of my settings in the next few days. VERY cold out (0*F) at the moment.

 

[CPT Davenport]

Thanks,

BRRRRRRRRRRRRRRRR!!!!!! I thought low 30's was feeling cold!

 

[Vic Harder]

On my Victron Charging devices (Orion and MPPT) absorb is set to 14.4, float to 13.4.

Shunt is set to 14.4 charged voltage, 2% tail current.

So yes, absorb and charged voltage should be the same.

 

[CPT Davenport]

On my Victron Charging devices (Orion and MPPT) absorb is set to 14.4, float to 13.4.

Shunt is set to 14.4 charged voltage, 2% tail current.

So yes, absorb and charged voltage should be the same.

Perfect, done! Muchas Gracias! I cant wait to test it the next time the sun comes out! Gotta make hay (or watts) when the sun's shine'n and getting topped off to 100% SOC is always nice when mother nature is picking up the tab.

 

[CPT Davenport]

Synchronized absorption volts on CC to 100% SOC volts on shunt and got a couple hours of sun on it. Fully charging now! 100% is better than 95%.

 

[pawleyk]

On my Victron Charging devices (Orion and MPPT) absorb is set to 14.4, float to 13.4.

Shunt is set to 14.4 charged voltage, 2% tail current.

So yes, absorb and charged voltage should be the same.

Not that Vic needs my reassurance, but this is 100% correct. This is a common issue with DIY installs, and even a lot of installers. Even Battleborn had it wrong on a blog way back. But the full voltage on the shunt should match or be very slightly lower than your absorption setting on your chargers.