Smart BatteryProtect LVD

dreadlocks

Well-known member
FYI: this just came out, new version of the old BatteryProtect but now w/Bluetooth.. this lets you connect w/Victron App and program it to cut off or re-engage at any voltage you want.. pretty big improvement because the limited programming was my only real complaint.


Think I'll be upgrading because the default programs my dumb BatteryProtect came with are rather poor for my Lithium Setup.. I've got it to disconnect at its highest voltage now and thats only 5% SOC on my BattleBorn.
 

dreadlocks

Well-known member
yeah I've been using my BMV to enforce custom set points and over voltage but this does alot of it internally.. unfortunately it does not look like you can set high voltage disconnect, which woulda been very usefull if it coulda latched close once recharged.

One thing that strikes me, now you can stage out your appliances.. put these right on a few circuits, like say you want your fan/furnace to cut out at like 65% SOC, your lights at 50% SOC and your fridge at 40% SOC you can do that now and tune each one for their respective cutoffs.

here's some screenshots I took of the app:
503928 503929 503930
 

jacobconroy

Hillbilly of Leisure
Dude, I was looking at this on Amazon and it prompted my post about LVDs yesterday. One of the reviewers complained that it was programmable for voltage integers only (12 volts, 13 volts, 14 volts, etc.). Your app screenshot looks like you can define the voltage at will. And, it has a remote disconnect. I think that is what I need. Thanks for posting it.
 

dreadlocks

Well-known member
This just appeared on Amazon's website's today thats how I found it by happenstance, I wrote a review for the old non smart battery protect earlier this week and instead of the usual few hours before I got the "thank you for your review" email it took a few days and finally appeared in my mail today.. since it took so long I checked it to make sure the photos attached correctly and sure enough there were new "Smart" models w/Bluetooth suddenly that were definitely not there when I wrote the review.. and yeah the smart ones you can configure to any voltage thresholds you desire, no longer confined to the 9 pre-defined programs.

I can only surmise my product review got put on hold because there was a pending product change, or something like that.
 

jacobconroy

Hillbilly of Leisure
What do you think a good cutoff would be for a 3.8 liter V-6 in a Jeep? I'd really like to leverage the engine battery while at camp, but I also would like to make darned sure that the engine will turn over. I was going to start at 12.3 volts.
 

dreadlocks

Well-known member
12.3 would be a good starting point, thats what my dash cam LVD is set at and it always starts up my diesel just fine even on the coldest morning... test it around the house and see what your comfortable with, if they are just luxury loads like radio and lighting then set it and see if you get a reasonable runtime.. if you need to keep food fresh in a fridge, well then you might want a bit more runtime and figure out your own safety margins.
 

jacobconroy

Hillbilly of Leisure
I read the schematic in your post. Although it indicates that the Victron should go between the battery and a load(s)...I intend to put it between my engine battery and coach battery. So, when both batteries hit 12.3 the Victron should disconnect the two batteries. From that point, the loads can continue to use the coach battery down to 12.0 (or maybe lower in a pinch. It will have it's own LVD to the loads). The plan was that the engine battery will stay at 12.3 to start.

Am I understanding this correctly? I can add the second Victron for the coach-to-load issue later.
 

dreadlocks

Well-known member
no, this is a low voltage disconnect.. it disconnects loads automatically before the battery goes flat or gets damaged.. it goes between batteries and loads traditionally.

you just need an automatic connect relay, just connect the batteries when engine is running and isolate em when they are not..

or are you in need of more capacity and trying to leech some extra power off your engine batt?
 
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jacobconroy

Hillbilly of Leisure
You got it...trying to leach some juice from the engine battery without fear of killing it. Another fellow on the portal managed to fit a group 31 under the hood of my rig. If I can do that and mooch from it down to 12.3 then I should be all set.

My current National Luna setup has a 100 amp fuse between the engine and coach batteries and it has never blown. It also disconnects the two batteries at 12.5 volts. I'd hoped this means I can use the 100 amp Victron LVD between the two batteries instead of the NL system and choose my own disconnect voltage (and not be afraid of alternator charging amperage).
 

dreadlocks

Well-known member
You might be able to get away with something like that, I'm not sure honestly, I need more brain activity than I have this late on a Friday to compute this clever idea.. however personally if I were in your shoes I'd toss in a small deka battery dedicated for ONLY starting and then use a dual house battery setup (dual 6v gc) for winching and overlanding.. I know for my TJ lots of ppl make dual battery trays for em and there's plenty of room for a Deka somewhere near starter.. this is exactly what I did on my Westfallia.
 

jacobconroy

Hillbilly of Leisure
I hear ya and would have already added another battery. But, I am out of room (2-door JK) and the rear of the rig is weighted down too much as it is. Simply can't afford another 80 lbs. coach battery in the rear.

For $78.20 I might give it a try. I have a feeling that it will work. The only question is if the alternator amperage will fry the Victron while the coach battery is pulling a charge load through it? I have no idea.
 

dreadlocks

Well-known member
if your not running a winch through it and just using it for dropping engine battery from a low load env that will never happen, your battery would have to be capable of accepting 100A charge or you'd need a load of 100A.. Your battery likely cant take more than 20A of charge current even if deeply discharged, you'd probably be fine with the 65A Smart BP.. I run the 100A because I am planning on a 1200VA inverter to run my coffee maker.
 

jacobconroy

Hillbilly of Leisure
OK, I've been outside staring at the Jeep for a couple of hours. While on the verge of reinstalling the National Luna Power Pack....I've never really liked it. Don't get me wrong, it's a great "starter" battery system, but it is just too big and I need more capacity and automation.

So, The new plan is to order a second matching 125 aH group 31 battery and build a special cabinet to mount one behind the driver seat & one behind the passenger seat as low as possible (slightly tilted). These will be wired in parallel.

Then I plan to install:
  1. An isolator or relay or solenoid to disconnect the two rear batteries from the engine battery when the ignition is off.
  2. A NC relay or solenoid between the two rear batteries to automatically disconnect them from each other when the NOCO is maintaining the batteries (so that they will complete maintenance individually...not as a pair in parallel).
  3. A 120 volt NC SPDT relay to open the #2 relay/device with 12V injection during battery maintenance (I found one on Amazon for cheap). This will have a small current draw during maintenance, but I figured it can draw from the batteries being maintained. One battery might charge a little slower, but there will be no parasitic draw at any other time.
What do you think? Good plan? I should have a full 125 aH to use at camp. This will let me run my fridge and heater without being miserly for at least a two-night trip. Also, what devices would you recommend for #1 and #2? My big batteries say, "do not charge with more than 30 amps)...so does that mean that 100 amp ratings on device #1 will be plenty?
 

jacobconroy

Hillbilly of Leisure
I've been reading up on my charger at NOCO. According to this, I can use a two-bank charger while both banks are connected in parallel without separating them during charging....is that right? If so, my life just got easy.

The only difference from this example is that I have two 125 Ah batteries.

506378
 
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