MPPT and bus bars in steel cabinet?

[timselectric]

That is very well a possibility.
It takes a bit of effort to burn wood, around here.
You have to either be trying or really screwing up.

 

[SilverbackMP]

I also prefer installing in a non conductive setting. I do have doors that can be closed and locked if needed to protect from young curious minds if needed.

My DIY battery boxes (3/4 inch birch ply) are lined with 1/4 inch rubber floor material (also serves as a bit of cell compression relief). The floor of my shed also has the same rubber sheet flooring.

Could also use it on the top and bottom of metal shelves and perhaps coat other metal bits with flex seal.

Also, also metal shelving, boxes, server racks (I have a small server area in there too) are properly grounded.

 

[JJJJ]

takes a bit of effort to burn wood, around here

I spent five years in southern Indiana along the Ohio River. Humidity there was very high. Don’t recall any forest fire alerts during those days.

 

[timselectric]

I spent five years in southern Indiana along the Ohio River. Humidity there was very high. Don’t recall any forest fire alerts during those days.

I'm across the river from there.

 

[OffGridForGood]

My DIY battery boxes (3/4 inch birch ply) are lined with 1/4 inch rubber floor material

I can see the rubber for electrical isolation - but if it were to catch fire, rubber burns/makes smoke - I think this is why they use the fiberglass sheets between the cells typically: electrical isolation without being a smoke/combustion supporting material.
Fire Marshal told me once: "Smoke kills far more people than fire"

Humidity there was very high

Dry wood is a fantastic electrical isolation material, wet wood not so much.
on the flip side, dry wood can burn easily, but wet wood not so much.

I built my DIY cells into packs in birch ply boxes too, and like @timselectric I was mostly concerned about the isolation of the cell cases so used fiberglass sheets in some, and the stuff they call 'fish paper' (you see this in electronics; kinda green stiff paper stuff) in the others, since it was thinner and cheaper than the fiberglass sheets. I like the physical protection of the birch boxes, using a non-conducting material instead of metal, lets' me sleep better.

 

[SilverbackMP]

I can see the rubber for electrical isolation - but if it were to catch fire, rubber burns/makes smoke - I think this is why they use the fiberglass sheets between the cells typically: electrical isolation without being a smoke/combustion supporting material.
Fire Marshal told me once: "Smoke kills far more people than fire"

Dry wood is a fantastic electrical isolation material, wet wood not so much.
on the flip side, dry wood can burn easily, but wet wood not so much.

I built my DIY cells into packs in birch ply boxes too, and like @timselectric I was mostly concerned about the isolation of the cell cases so used fiberglass sheets in some, and the stuff they call 'fish paper' (you see this in electronics; kinda green stiff paper stuff) in the others, since it was thinner and cheaper than the fiberglass sheets. I like the physical protection of the birch boxes, using a non-conducting material instead of metal, lets' me sleep better.

That’s why it’s in a shed. It’s not a EV. Besides, the spray foam in the walls, floors and ceiling would likely release worse stuff. At some point, more and more risk mitigation starts running into the of law diminishing returns.

 

[JJJJ]

lets' me sleep better.

Ah yes. The true reason we are here and bounce our ideas off of others.

 

[OffGridForGood]

That’s why it’s in a shed. It’s not a EV. Besides, the spray foam in the walls, floors and ceiling would likely release worse stuff. At some point, more and more risk mitigation starts running into the of law diminishing returns.

I agree,
I put my entire solar set up next door in a steel building, concrete floor.
I make sure all the connections are tight, check them on occation, properly sized wire, MC for the PV DC as required around here, fuses and breakers in sensible locations. In the early days of my set up I ran around with a lazer temperature probe and checked what temps the wires and components got on a bright sunny day, or while my Official Solar Tester (wife) was pushing the system to the limits. That gave me a lot of confidence in the system seeing the wires stay at low temps even under high load.
One of the best parts of the DIY solar forum is reading the Up-in-Smoke postings and the safetey check to see what others may have discovered and we can learn from the easy way, before it is a problem.
I have learned a lot about the electrical code from members here on the forum.

 

[SilverbackMP]

My other issue was that I was under a time crunch. But I don’t think I would build the boxes much differently. The cells are individually wrapped in 2-3 layers kapton tape. Most of them anyway. I ran out for the last box and some are separated by flexible cutting board material.

 

[Zwy]

I'm inclined to put all of the solar controls into a steel cabinet and run the #2 wires to my multiplus 24 2000 which will be mounted next to the steel cabinet (with a door on it)
Put some fans in there to cool the equipment.

Why? I want to contain a fire in the event something bad happens.

Any opinions?

I would not do what you plan on a house system. On my truck camper, I mounted a toolbox to the rear and installed the Growatt AIO inside. It does get quite warm in there even with the inverter off and just the MPPT charging the battery. Yes, it does have a fan and outlet that is thermostatically controlled.




What are you afraid of? I prefer wires in conduit. I do have my Batrium K9's for my house system outside the battery box as these generate heat when balancing. Common sense should prevail.

Build a system like this where wires are protected, the battery is contained in a heavy steel box. You can look at the links in my signature if you want to see how I put things together.

 

[SilverbackMP]

My other issue was working around the self-imposed physical constraints of that steel cabinet. Mine has an 18 inch depth. Would have been much easier to figure out a design with the 24 inch depth version (which also has the benefit of being available in many more sizes height and width wise).

 

[webbbn]

That is very well a possibility.
It takes a bit of effort to burn wood, around here.
You have to either be trying or really screwing up.

This is from my driveway a couple years ago!

 

[webbbn]

And, several years ago a makeup mirror focused the sun from a window onto a towel and almost burned my house down. The fire fighters couldn't find any evidence of where the fire started after more than an hour of searching. I found the pile of ash on the vanity after they left, which was the only clue. If anything flammable had been above that, I'm sure the whole house would have gone.

In any case, I see alot of posts from southern CA and Texas, where it can also be very dry, and, the only protection against a poor connection is not allowing the heat/sparks/flames produced to start a fire. If fire is not a concern, then do what you want, but no one should assume that large wire, breakers, and fuses are 100% protection.

 

[timselectric]

And, several years ago a makeup mirror focused the sun from a window onto a towel and almost burned my house down. The fire fighters couldn't find any evidence of where the fire started after more than an hour of searching. I found the pile of ash on the vanity after they left, which was the only clue. If anything flammable had been above that, I'm sure the whole house would have gone.

In any case, I see alot of posts from southern CA and Texas, where it can also be very dry, and, the only protection against a poor connection is not allowing the heat/sparks/flames produced to start a fire. If fire is not a concern, then do what you want, but no one should assume that large wire, breakers, and fuses are 100% protection.

You need a humidifier.

 

[webbbn]

You need a humidifier.

You're probably right!

 

[OffGridForGood]

This is from my driveway a couple years ago!

a makeup mirror focused the sun from a window onto a towel and almost burned my house down

Surprised the local FD had an arial fire suppression aircraft, glad they saved your house!

 

[webbbn]

Surprised the local FD had an arial fire suppression aircraft, glad they saved your house!

Oh, that wasn't the local FD. There were hot shot crews from Oregon parked across the street for that one.

Bighorn Fire - Wikipedia

en.wikipedia.org

 

[OffGridForGood]

Oh, that wasn't the local FD. There were hot shot crews from Oregon parked across the street for that one.

Bighorn Fire - Wikipedia

en.wikipedia.org

yeah I was playing with ya - implying the photo with the fire suppression actually Was your house fire, just joking around.
What the heck can burn in that pic? the tumble weeds? All I see in the pic is rock, dust and cacti, any of those burn?

 

[webbbn]

yeah I was playing with ya - implying the photo with the fire suppression actually Was your house fire, just joking around.
What the heck can burn in that pic? the tumble weeds? All I see in the pic is rock, dust and cacti, any of those burn?

I guess you haven't been to the desert. Look in the bottom of the picture at the dried bushes. We go through cycles in the Sonoran Desert, with heavy (for us anyways) winter rains, followed by months of no rain where most of the vegetation dries up and is extremely flammable. We in Arizona, at least, joke about the four seasons of California: earthquake, flood, fire, and drought. We don't get many earthquakes, but we definitely get the other three!

 

[SilverbackMP]

I guess you haven't been to the desert. Look in the bottom of the picture at the dried bushes. We go through cycles in the Sonoran Desert, with heavy (for us anyways) winter rains, followed by months of no rain where most of the vegetation dries up and is extremely flammable. We in Arizona, at least, joke about the four seasons of California: earthquake, flood, fire, and drought. We don't get many earthquakes, but we definitely get the other three!

Add the earthquakes back in and that’s basically south Afghanistan. Ima good.