Question about the Victron Energy Smart Battery Sense

Buckster

I am planning to purchase the Victron Energy Smart Battery Sense. I realize it needs to be physically connected to my battery but want to make sure that it connects to the Victron Charge Controller via Bluetooth.  In other words, can someone confirm that it does NOT need to be connected physically (hardwired) to the charge controller AND the battery?  Based on these answers, that appears to be the case.

I obtained the idea for this from Will Prowse, but in this video, he connects the Smart Battery Sense to both the controller and the battery.

AnOldUR

There are only two lead coming from the Smart Battery Sense. One for connecting to the positive and one for the negative battery posts. It networks with your other Victron devices via Bluetooth.

Buckster

I have a follow-up question. Is it true that the smart battery sense and charge controller ONLY keep the solar panels from charging when you hit the low temp threshold?  In other words, if I am connected the shore power, will that override the low temp sensor and charge the battery?

If that's the case, I am going to look into some kind of warming pad when we are winter camping and connected to shore power.  If any of you are utilizing something like that, I'd love to hear what you are using.

techietab

Buckster said:

I have a follow-up question. Is it true that the smart battery sense and charge controller ONLY keep the solar panels from charging when you hit the low temp threshold?  In other words, if I am connected the shore power, will that override the low temp sensor and charge the battery?

Correct. Shore power would bypass the Victron controller and thus any Victron settings would have no impact on shore power behavior.

I just installed a Facon CW-T1218 heater pad (intended for RV tanks) below my two LiFePO4 batteries in my tongue box. The pad is configured to turn itself on at 45 F and disable itself at 68 F. I attached it to a 1/8" aluminum sheet that I cut to fit into the box below the batteries, and installed a thermal transfer pad on the bottom of each battery to bridge between the aluminum and the battery casing. Wrapped the whole thing up in 3 layers of 3mm reflective radiant barrier around the sides.

I haven't had low enough temps here to test yet. Was planning to make a post here later when I'm able to collect some temperature stats to demonstrate efficacy (or lack thereof).

tomtek

After you have the Smart Battery Sense installed then you join all Victron devices to the same VE.Smart network and the Smart Solar charging controller will pull temperature and voltage via VE.Smart Bluetooth from Smart Battery Sense or a SmartShunt if you have the Temperature Sensor option for SmartShunt.   

As far as temperature control you don't mention the battery make and model.   Some batteries have temperature cutoff builtin to the LifePO4 battery BMS.  The BMS will prevent charging and discharging during low and high temperatures in factory constructed LifePO4 batteries.   If you want to continue charging in cold temperatures then a battery heater as mentioned above or relocate battery to cabin to keep it warm.