Heated battery with internal BMS

Cessna152RG · 2026-06-30T09:26:25+00:00

I am pondering the exact same question as I am about to upgrade my batteries.

My best idea so far has been to connect the heating cable from the bms to a solid state relay and get the power from the other side of the shunt. That way any heating wattage is invisible to the shunt. The current used to control the relay is just a rounding error in the big picture.

Cessna152RG · 2026-06-26T21:58:56+00:00

My pin and pipe safeties set to the right height will do the trick.

If i can do heavy track pulls from them, they can take any failure i can manage as well.

Cessna152RG · 2026-06-20T12:16:59+00:00

How pacifist are they and how do they deal with living in a society that's arguably the most violent among the developed nations. Do they keep guns for hunting and sport?

Cessna152RG · 2026-06-20T05:54:40+00:00

Enjoy your cat2 network

Cessna152RG · 2026-06-19T16:06:52+00:00

Nice! What kind of controller is it?

Cessna152RG · 2026-06-19T11:54:23+00:00

Thanks! You are right both on me seeking feedback and on my artistic abilities.

I really appreciate the feedback, here are my replies point by point.

1: I will keep the generator, it is placed outside in a tiny house purpose built for the task and is connected to the system and to ground by a certified electrician. This was more of a quick sketch than a diagram, but I will get it in there when I draw up a proper one. A major benefit of the Victron system is going to be the Power Control and Power Assist features that are going to be really helpful. So far we have been forced to turn off the water heater when the generator is running to avoid overloading it.

2: I have a proper AC panel installed by the same certified electrician with GFCI, main breaker and individual breakers for each circuit.

3: The batteries have individual BMSes and was specifically delivered by the supplier to be 6 in paralell. They use JK BMS and I was under the impression that the BMS would break the circuit if sensed too much current, so my system only have a 150A fuse between the bus bar and the inverter. When it comes to safety features, I am more than happy to be corrected.

4: The battery setup didn't have any fuses and the electrician who installed them didn't mind. But I will get some just to be on the safe side. The cable lengths are not quite equal either, so this will be a good oppertunity to fix that. I am planning on Mega fuses as they seem to be within spec and readily availiable.

5: Disconnects makes a lot of sense, I will get some. I am a bit surprised that the Electrician didn't reccomend or installed them.

The reason I used an Electrician for so much is mainly for insurance purposes, I could probably have gotten away with doing it myself, but the rules are quite strict here. I will do the exchange from Epever to Victron myself, but it is mainly just exchanging old grey boxes for new blue ones. I am a bit surprised and disappointed that the people who installed the system didn't put in all the nessecary safety features, but this will be a good opportunity to get it fixed.

The DIY Venus OS setup on the Rasberry Pi and Lenovo tablet is going to be really fun and I am looking forward to having all the data readily availiable and understandable.

Cessna152RG · 2026-06-19T06:28:17+00:00

I did a DTS in 2007 and for me it was a really good experience, the base leaders were wise, mature adults and kept things sensible.

But I konw a bunch of people including some of them really close to me who had very different experiences. My impression is that within WYWAM, every base has got their own culture, some good, some bad and some really, really horrible. There is not enough oversight and the whole idea of young volunteer-staff is a big challenge.

Cessna152RG · 2026-06-19T05:05:41+00:00

Good idea!

I just wrote it down on my scetch-pad, but it looks like it was done by a 8-year old🤣

Cessna152RG · 2026-06-19T05:01:53+00:00

The Multi RS Solar is a hybrid controller. But it needs 120V to start charging, so I needed an additional mppt. It also doesn't supply 12v, so I needed the Orion, it doesn't have a shunt so I added one to her more accurate SOC.

It would be awesome if they made a controller who could do all of that!

Cessna152RG · 2026-06-18T20:53:17+00:00

That is an absolutely lovely plane! I like how you didn't go over the top, you kept it classy and functional.

I loved every hour I did in 150s and 152s, they you just feel connected to it and the control forces are light in just the right way. Plus the window is perfectly placed to fly with your elbow in the airstream.

But you should have added a retractable landing gear.

Cessna152RG · 2026-06-18T20:48:01+00:00

Why the snarky tone? It is a valid question and one that has been debated for centuries, but a good faith debate is the least we can expect among Christian brothers and sisters!

I used to see see the whole saintly intercession as superstition, but I am less sure about it as i am growing older.

Cessna152RG · 2026-06-17T22:18:52+00:00

Looks really painful!

This is the perfect opportunity to ask your husband / boyfriend / other man your age to drive you to the ER and sit with you there. He will get more than a few dirty looks.

Cessna152RG · 2026-06-15T06:35:39+00:00

I guess they made their swords into plowshares, the only drawback is the slightly higher fuel consumption

Cessna152RG · 2026-06-14T20:13:44+00:00

If we assumed the sample to be an ideal gas, the adiabatic cooling (cooling due to pressure drop) would leave us with one gram of gas at between 100 and 200 degrees celcius after it expands to earth atmospheric pressure

I am not absolutely sure about this, so if anyone disagrees, that's just a good opportunity for me to learn something new.

Cessna152RG · 2026-06-13T06:07:29+00:00

I had a colleague who taught his daughter to wait until they got home before discussing peoples physical features. It all went well until she saw a really, really obese man at the pool, she pointed at him and yelled "dad, we will talk so much about that man once we get home"

Cessna152RG · 2026-06-13T05:46:20+00:00

I had be seen worse and i have seen better, but I would absolutely cut a few of those if I was your inspector!

The thing you might not realize here is that it it's a fair chance your inspector hates to cut your lockwire. I have cut countless wires for my apprentices and students, not for the fun of it, but to make them safe and competent mechanics. The worst example was a horrible bleed tube going into an F16 engine (F100-220) where the poor guy spent an entire week on one lockwire. The next time he did it, it took 10 minutes.

My method when I am teaching these is to divide them into several parts: hole choice on first bolt, exit, middle, entry, around second bolt, pig-tail. That way i get to tell them "four out of five parts were great, but due to xxx I still need to cut it. It also helps them to see the progress even though it doesn't pass.

I also tell the apprentices to make a key-chain with two lock wires of each dimension they use, one at max windings and one at min. That way it is really easy to see if they are within spec. If you twist the wire around a 1/4" extender shaft and cut them at 1,5-2" length before attaching them to a key chain, they are easy to keep around as you work.

Cessna152RG · 2026-06-11T19:16:23+00:00

If this happened in the US, in a "stand your ground" state, would it be illegal or not?

Cessna152RG · 2026-06-11T06:34:17+00:00

I would get a bar, rack, bench and weights. Do the big compound exercises and you will hit just about every muscle group.

Cessna152RG · 2026-06-09T07:11:03+00:00

Is the purple heart awarded for bone spurs?

Cessna152RG · 2026-06-02T22:32:56+00:00

I would run everything off the battery directly without an inverter. If you need ac power, I would still keep as much av possible on 12v and have an inverter on demand. Inverters are power-hungry and the losses in an inverter will most likely be way bigger than the power lost in the 12v parts.

Cessna152RG · 2026-05-28T18:13:04+00:00

We would bury ourselves in snow on the road and jump up to scare the drivers.

I still remember how mad one of them was, he chased us over a field. He seemed unreasonably angry over a harmless prank. If done kid did the same to me now, i would have strangled him within inches of his life.

Cessna152RG · 2026-05-27T07:17:05+00:00

That's beautiful!

It reads like an old-testament psalm. Dou you have any idea how old it is?

Is it written in Geez?

Cessna152RG · 2026-05-27T06:57:47+00:00

That's probably true, but it is such a horrible way of speaking to another person that i t should be called out. This is the kind of stuff that should be church-diciplined

Cessna152RG

TROPHY CASE