Recent content by ohthetrees

You might be right about this. I'm an optimizer, and the idea of the batteries being at 100% by 10am worries me a bit, but maybe I'm being too much of a perfectionist. Or maybe I just need to find the "right" charge voltage! That will be an experimental process though.

I appreciate your input, but I don't agree. You say I'm "getting away with my design" and that Q-Dog mentioned my design was wrong. Yet I cited sections of both the Victron Cerbo manual and the REC BMS manual that indicate my architecture is just fine. Nobody has mentioned a concrete reason, nor...

I don't think I'm going to go in that direction. I really like how my system degrades gracefully if the network goes down, but if the network is up I have centralized logic. The problem is that I gave it a poor parameter for when I'm away. I think I'm on the right track to giving it a better...

This was a great link, just what I was looking for. As for why 3.25v wasn’t cutting it, I speculate that there was a cloudy week then the BMS cut the battery off, so it could never recover. I think I’ll do a little testing while I’m on board, maybe try 3.32v to start.

I respectfully disagree with that. I believe it is appropriate for an external BMS to be the "authority" on what charge/discharge treatment the batteries should experience. The REC Active BMS has a specific feature that allows it to communicate and control a Victron GX system. I don't think REC...

I live 8 months a year on a 50' sailboat with 1800w of solar, and a 13.5 kWh bank I made from bare cells. My BMS is an REC Active BMS controlling the whole charge system via a Victron Cerbo GX. It is performing absolutely fantastically when I live aboard. The problem is my "layup settings"...

I've had a few people direct message me about getting this file. Here you go! Fusion 360 Project (so you can modify yourself): https://a360.co/3JjapBQ STL, STEP, and 3MF files in attached zip.

That first picture (Clamp) is the kind of thing I'd probably make a lot of.. And then it would live its life in the sun.. ASA is very UV resistant, and will hold up fine outside.

You can do all those things projects with a 3d printer. There are all kinds of filaments with different properties available. I live on my boat, so I have a Prusa Mini which is very compact, yet still has a decent 180x180x180mm print area. I use it all the time for mechanical and outdoor parts...

Thank you for that. I'm aware of this approach, and went so far as to buy the components, but I realized that with my install, I don't expect to the BMS to routinely actuate the ML-RBS. In fact, since opening the ML-RBS is a last-resort action for my BMS if everything else goes wrong, my hope is...

I even think the the REC could turn the RBS on (close it ) too. It is true that the RBS specifies a pulse, and the REC provides an always-on signal, so seemingly incompatible. However, I called Blue Sea, and spoke to a guy who seem to know his stuff, and he told me that while they haven’t...

I have the “Main normally closed” (REC terminology) BMS relay output hooked up to the open(disconnect) signal wire on the ML-RBS. The normally closed relay is open when the BMS is happy. When the BMS detects a fault, or is turned off, it closes the normally closed relay, which opens the...

I forgot to update my own thread on my progress! I ended up making wire interconnects. I used AWG 4 (ampacity 160a) for the parallel connections, and AWG 1/0 x 2 for the serial connections. Each 1/0 cable has an ampacity of 285a, so total of 570a for serial connections. I'm happy that they have...

Just thought I'd share my implementation of a spring based fixture. I have separated each cell with a thin sheet of silicone. I like that material because it is heat resistant, provides some chafe protection, electrical insulation, and it "clings" to the cells with no adhesive, so it is easy to...

I’m not familiar with that particular inverter. However, many inverters (for example my victron multiplus) have the ability to “trickle charge a small starter battery”. What I have not seen yet is one that can charge with a different charge profile and voltage to the secondary battery bank...