12v Refrigerator

[chrisblessing]

Greetings. I have installed a Dometic/Waeco CR50 12v refrigerator. I've currently got it directly connected to my 100Ah LiFePo4 4s battery pack. I wonder if it is recommended to connect the negative to my Daly 100a BMS. The refrigerator itself has a low-voltage cutoff of 10.7v which seems to me just a bit too low.

Thank you.

 

[Dzl]

Greetings. I have installed a Dometic/Waeco CR50 12v refrigerator. I've currently got it directly connected to my 100Ah LiFePo4 4s battery pack. I wonder if it is recommended to connect the negative to my Daly 100a BMS. The refrigerator itself has a low-voltage cutoff of 10.7v which seems to me just a bit too low.

Thank you.

I believe everything should go through the BMS in order for it to do its job. Other devices have low and high voltage cutoffs, but it is the BMS that is ultimately responsible for battery protection, and the BMS is the only device aware of cell level monitoring/protection (which is what's important when it comes to protecting your battery). Also I agree with you, that low voltage cutoff point is a bit too low for comfort.

 

[Pierre]

I believe everything should go through the BMS in order for it to do its job. Other devices have low and high voltage cutoffs, but it is the BMS that is ultimately responsible for battery protection, and the BMS is the only device aware of cell level monitoring/protection (which is what's important when it comes to protecting your battery). Also I agree with you, that low voltage cutoff point is a bit too low for comfort.

I agree with Dzl about running all loads through the BMS. I don't think that the low voltage cut off set on the fridge is too much of a problem. Just set your BMS to cut off higher at about 11,4v . Dometic design seems to be quite comfortable with that setting. If you cannot access the settings on the BMS do a discharge cycle to see at what voltage the BMS disconnects the loads.

 

[chrisblessing]

Thanks pierre and Dzl. I have connected the refrigerator negative to the BMS. For a bit of background, the previous wire was too small a gauge and I had 3 connection points between the refrigerator and the battery, resulting in excessive voltage drop. With heavier gauge wire and only one connecting point it runs as it should.

Thanks again for your input.