24v LiFePO4 SmartShunt settings

[mmm33732]

I recently added a Vitcron smart shunt in place or my other battery monitor in order to sync with solar assistant. I seem to be having some issues with what to put the settings at. I'm not sure what to put the charged voltage at as well as tail current and current threshold. The manual recommended 26.4v for a 24v system. That seems too low as it always shows the SOC at 100% anytime to voltage is above that but the battery is not at actually at 100%. Basically, what do you have for all your setting if you have a 24v LiFePO4 setup? (obviously Ah is relative, but everything else should be pretty standard)

If it matters, I currently have my charger/inverter settings with a battery absorption charge voltage of 28.5V, Battery float at 27.2, and Low voltage shutdown at 24V.

Thanks.

 

[LakeHouse]

Set your ‘charged’ voltage slightly below your absorption voltage. Something like 28.3V if you’re going to stick with your 28.5V absorption voltage. And tail current at 3% to 5% of your Amp Hour capacity.

Many here will tell you that 28.5V is too high, but I’m not one of them. If your cells are balanced enough that the BMS isn’t shutting the pack down at that voltage, you’re fine.

 

[Sky-HHI]

You may want to look at Andy's you tube channel or go to his web site off-grid-garage.com . At the top right go to tools then, my settings, he has his setting for a victron smart shunt and a link to a video about the settings. His you tube channel is full of great information.

 

[AF_Bob]

You may want to look at Andy's you tube channel or go to his web site off-grid-garage.com . At the top right go to tools then, my settings, he has his setting for a victron smart shunt and a link to a video about the settings. His you tube channel is full of great information.

Thank you for mentioning Andy's website. I have been wondering why my Victon SmartShunt doesn't capture the current being drawn by my Victron Solar Charge Controller (Bluetooth constantly on) plus my Victon IP65 Smartshunt (Bluetooth constantly on) and drawing power continuously. I'm guessing perhaps both units draw 12 mA and if you compute 12mA X 24 hours X 30 days, the current used would be 8.64 Amps in a month! That's 8.64% of my 100Amp battery.

My Smartshunt was always showing 100% SOC unless I started to actually power an external device with it. It wasn't until I watched Andy's video, where he mentioned what the CURRENT THRESHOLD setting meant--that I finally realized any current draw less than the standard setting (.10A...or 100mA) would NEVER get captured. Andy left his setting on .10A but since I leave my solar charge controller and smartshunt connected/powered, I'm going to change it to 0.01 A (or 10mA) to see if my SOC finally starts decreasing to account for the constant (albeit small) continuous current draw. In most situations, I'm guessing most people use their power station routinely, but I have 3 of them and the most current one (which I built DIY) basically sits idle unless I lose power in my cabin.

 

[740GLE]

Biggest thing is having the smart shunt tell the SCC actual battery voltage via smart network.

Once you set smart network up I think the SCC settings override the shunt voltages, only thing left is AH to fill out.

 

[AF_Bob]

Biggest thing is having the smart shunt tell the SCC actual battery voltage via smart network.

Once you set smart network up I think the SCC settings override the shunt voltages, only thing left is AH to fill out.

Thanks. I do have the Victron network setup so it feeds current and voltage. The issue I was having was that the current draw from the SCC and Smartshunt wasn't being considered when calculating the SOC because the current threshold was set too high. Even though the voltage of the battery was decreasing and being displayed correctly on the Smartshunt App, the shunt never registered ANY current draw out of the battery since it ignores 99 milliamps or less, by default.

Since the default threshold current is 0.1A (100 milliamps) so you could drain 99 milliamps continuously until the battery dropped to 0% and the SOC was still reading 100% because it never detected any current draw through the shunt. I wasn't able to program the current threshold to 0.005 Amps since it only has 2 digits after the decimal point, so I changed it to 0.00A and then the current draw from the battery started showing up on the display (fluctuating between 0.00 and 0.01 Amps and occasionally 0.02 Amps). I'm assuming that once the 100A battery drops enough to display 99% SOC, the App will now show me that. All this SCC and Smartshunt stuff is totally new to me. I incorrectly assumed that the SmartShunt would consider any current draw from the battery when determining the SOC...but it ONLY considers current above the threshold setting.