Victron EnergyBlue Power Bp-220 Battery Protection System

I use it to automatically turn on and off my 48V pure DC air conditioner, with a 48V LFP battery I like it to power down the air conditioning when voltage drops below 51.2V and have it automatically restart the next morning when the sun recharges the battery above 52.6V. I get to use 100% of my harvest by the Full Battery air conditioner while having enough reserve juice left in the batteries to keep the critical equipment running on the inverter through the night. A solid state relay doesn’t spark and doesn’t wear out so it truly is an ideal piece of equipment with a well designed app.My only complaint is that the terminals are stainless steel with a small pad surface area, and if you are pulling large loads, be careful that your ring terminals are well conductive and screwed down tight (I seem to have an issue with tin plated terminals overheating) and that the wires are properly sized (FAT). Run your load and check that the terminals are not heating up. It is possible to fry this unit if the terminals run hot (speaking from experience). All the reviewers complaining about only being able to use this device one way.. do not need this device. Semiconductors / SSR’s only work one way you guys, get a clue. This is not a BMS. For me, the whole point is to cut off power to my Full Battery 24/48 volt air conditioners and heaters BEFORE the battery runs out, and to turn them back on when I have excess charge. So yes, it’s for controlling additional DC equipment such as motors, DC Heat Pumps, etc. You don’t need this for your inverter, your inverter can already be programmed to turn off at a specified voltage, that’s not what this solid state RELAY is intended for.

Being able to customize the turn off (and turn back on) voltages down to the decimal (and even 0.01 increments) was critical for my power setup in my SUV camper.I have a Dakota Lithium starter battery for my car's main battery, which has about 1600 Wh of power and recharges directly from the car's alternator. I also use that starting battery to charge my Ecoflow Delta 2 (which only has 1000 Wh). Since my starter battery charges at about 60 Ah via the alternator, it made a lot of sense to trickle charge the Delta 2 from the car battery (with this smart battery protect to turn off the charging before the car battery got too low). I have the Delta 2 charge through an XT60i cable connected to the output of the BatteryProtect (so it charges at 12V 15A, a.k.a. about 180W). This also means it's all DC-to-DC, rather than trying to charge via an AC inverter (which would be DC-to-AC-to-DC).I was able to set the BatteryProtect to turn off at around 12.60V (about 40% of starter battery remaining), and have it not turn back on until it reaches about 13.30V. Different off vs on values were critical, since when the Ecoflow is charging at 180W, the voltage dips by about 0.65V.I've been on a 3-week car-camping trip and this setup has been working flawlessly!

Works excellent. Exceeded expectations. I reccomend this to anyone with a lithium battery. Just be sure to use some sort of appropriate circuit protection

It does work, and I am able to control it via the REMOTE input. However, just like Victron's 12/24V Battery protect, their 48V battery protect also has huge problems just charging the capacitors in a small unloaded inverter without thinking there's a short or over-current (when there isn't).In addition, there is significant leakage between the IN and OUT terminals when the device is turned off. So much leakage, in fact, that when the unit is turned off the voltage builds up all the way to the battery voltage and causes the inverter to try to kick-on every few seconds. I had to add a beefy 10 Kohm resistor between the output and ground to get it to stop doing that. Both the 12/24 and the 48V battery protect products have this problem.There is also no mention of whether the device has an external diode in it or not for dealing with voltage spikes from inductive loads (that would otherwise destroy the FETs).To be frank, Victron is supposed to be a high-end company. They should fix their products.

instruction is not the best if you are not technical