when is the best time to set the SOC on the shunt to 100%?
is it as soon as solar charge controller shows float, but also 200-300watts flowing in.
or will the watts eventually taper off closer to zero ?
what should i be looking for on the charge controller before i synchronize?
The best way I found is to disconnect the battery from whatever it's connected to then fully charge the battery with a battery charger then let it rest for 12 hours or so to allow the surface charge to dissipate. At that point you can then set the SoC to 100%.
You do not state what battery type (lead or lithium) or voltage or capacity so your 200-300W value on its own does not mean anything. Also, going into float on your Solar controller depends on how well set up it is. Provide a few details and we can advise.
For 12V lead acid charged by solar when the voltage is above approx 14.2V and the current is less than 2% of the battery capacity you can consider them fully charged. The 2% means for a 100Ah battery, the current is below 2A. Lithium are slightly different, but similarly, when the voltage is close to absorption voltage and perhaps current less than 4% is the default but others may have better views.
sorry its a lithium battery. i set up the parameters in the 100/50 controller based on 2 underlined lines below as suggested by the manufacturer:
Charging Charging Limit Voltage: 14.2V
Over Voltage Disconnect Voltage: 14.6V
Over Voltage Reconnect Voltage: 13.8V
Float Charging Voltage: 13.8V
Discharging Low Voltage Disconnect Voltage: 11.6V
Low Voltage Reconnect Voltage: 12.4V
Under Voltage Warning Voltage: 12.8V
right now for example, its showing float, PV 33.2 V, 5.2A, 172 watts ; battery 13.8V, 11.9 A
You still need to let us know the battery capacity. That does not sound like it should be in float yet unless it is a large bank. Can you share some screenshots of your SmartShunt settings and your solar controller settings if it is a Victron solar controller.
Is this the first charge for the batteries?
Your shunt should automatically sync if the settings are right.
