Victron Energy: Alternator/Solar Charging - LFP Battery System

[shade]

Blue Seas remote battery switch? 500A, low standby draw. Can be ordered in NO or NC, and will default to that position if the signal is lost.

Maybe. Do you think that would be a better LV disconnect than using a BatteryConnect and relying on an inverter's internal switch?

 

[Justin Cook]

Boo on Sterling, then.

Hahahaha yeah... that's not the first time I've said that. Great products as a general rule, but sometimes they're not quite keeping up with the times/demand.

 

[luthj]

I think it would work well. Both have their pro/cons, but could be made reliable enough for that purpose.

 

[b dkw1]

How would one get the blue sea relay to cut out at a certain voltage point like the Sterling relay?

 

[shade]

How would one get the blue sea relay to cut out at a certain voltage point like the Sterling relay?

The Victron BMV-712 can be used as a control device. I'm sure there are other ways, too.

BMV-712 Smart | Victron Energy

Communicate wirelessly between products and simplify system installation and enhance performance using the BMV-712 Smart. Find a dealer now.

www.victronenergy.com

Manual page 16 (pdf 18) discusses the relay.

https://www.victronenergy.com/upload/documents/Manual-BMV-700-700H-702-712-EN-NL-FR-DE-ES-SE-PT-IT.pdf

 

[luthj]

Post 30 discusses using the bmv to control a relay with inverted logic.

Help setting up LiFePO4 system w/ Victron Components

The BMV 712 supports triggering its relay output as follows. 16. SOC relay (Discharge floor) When the state-of-charge percentage has fallen below this value, the relay will close. The time-to-go displayed is the time to reach the discharge floor. Default Range Step size 50% 0 – 99% You may...

sprinter-source.com

 

[dreadlocks]

I tested my BMV-712 for this w/my dumb charger.. I used both battery voltage monitors to measure voltage on both sides of the charge relay.. I had it cut the relay at 14.4v and the power supply was 14.6v.. it would latch because once it dropped the battery from the charger the charger side would jump up to 14.6v.. This let me plug into shore power, charge the battery up then drop the battery and run the trailer off the power supply until I unplugged it then it would go back to running off the battery.

Ive changed it up since and now I'm feeding charge in through my solar charger.. gives me better control.

 

[shade]

Page 23 (25) of the manual goes into detail. The BMV-712 relay can go NC or NO, which is handy.

 

[shade]

While waiting for the Orion-Tr Smart to become available, I'll continue to spread the Wisdom of xkcd.


"Before I install any patch, I always open the patch notes and Ctrl-F for 'supervolcano', 'seagull', and 'garbage disposal', just to be safe."

Worst Thing That Could Happen

xkcd.com

 

[shade]

Could I use the same model of your Electricity station( I will call it like that) for charging a tesla model 3, or there are some huge differences?

Nothing in my system would be particularly useful for recharging a Tesla Model 3, but I'm certain that a Victron Energy sourced system could be built to do it.