Kazetsukai's Build

[Ninjakitty]

The remaining 4 months we're spent building at MIL house

[Ninjakitty]

Finished plumbing, electrical before leaving MIL house.

[synestine]

Originally Posted by kazetsukai

Its not yet working, mind you. There's no real reason it wouldn't work as I intend it, and I've been testing the components over a long period of time, so I should have some things of reference.

Which is exactly why I asked you about this. I love getting information from people who've done the testing and have the references.

Originally Posted by kazetsukai

Let me know if you'd like to collaborate or share source code on GitHub. The stuff I'm doing should be generic enough for others to use.

I did do two things you could consider "special", at least for wiring lights in a tiny house/house/bus-

I ran the power wires from the lights _directly_ to the automation box, not inline with any switches or controls.
I use momentary push buttons instead of switches.

I'd be happy to collaborate, just as soon as I get enough components working together that it makes it more than "I cribbed these libraries from other repos and wrote a few lines of glue code".

I will be running the light wires in a similar fashion to what you described, the leads running back to a wiring closet housing the relays and H-bridges, and the buttons being inputs for the system. It makes for a much cleaner setup, though specialized somewhat compared to a normally-wired system.

Originally Posted by kazetsukai

I did consider dimming functionality, and I would like it at some point. For now, I'm going for ON/OFF and using both groups (lights hard wired together) and zones (lights not wired together but colocated and intended to be controlled with the same button)- one local button press cycles a zone through different configurations, and that automation can turn lights on/off without worrying about a physical switch and its current state. Zoning is a good way to achieve light level control without the complexities of dimming.

My biggest "group" of lights is the walkway down the middle. The entire front to back I have staggered lights that are all linked together, this was done on purpose to make a "non fragile" / manually controllable zone that would work either from the solar electrical system or the bus electrical system, and be our backup lighting in case something went wrong with the solar.

Aside from that, the largest groups are 2-4 lights. With something 38+ lights in the ceiling, this means I have around 10-15 runs of wire, just from lights, going all the way back to the panel. You'll need space to do something like that.

I'm designing something similar, groups and zones. Groups of lights in the usual sense, to keep the number of wire runs down, and zones for normal use and automation. I'm also laying out the system in such a way that it degrades gracefully if something goes down, besides power I mean. I'm also using LED exclusively (Pucks and strips).

Originally Posted by kazetsukai

Either way, since I wired the lights the way I did, if I find a good way to do dimming (which I intend to do), I will not have to rewire much. I can just add the dimming hardware to the control box and move the appropriate wire to the dimmer.

Assuming these are DC lights, all you should need is an H-bridge and a sufficiently fast PWM driver. If you want to make your own H-bridge modules, they're pretty easy, but pre-built units are also pretty cheap on eBay. Just make sure they can handle LEDs, as a lot are made to drive motors and the electrical requirements are slightly different.

Originally Posted by kazetsukai

So first up, you don't necessarily need 220v for a mini split. Maybe two-zones require it, but you could also use two small, 110v mini splits. You may only need one on most days, as well.

True but from everything I've been able to find, if you want to run anything bigger than a 12k BTU unit, you do. And all the 2-zone units I've been able to find are 220v. I don't want two 120v units because then I'd have two condensers to find space for and protect. I'm hoping to not need much AC, as we're planning on doing a lot of boondocking, are not above chasing nice weather, and I'm aware of how energy intense it is, but with the way the weather's going, we may need it to handle the "freak" heat wave or "storm of the century"... And both of us can't sleep if the temperature gets too warm.

Originally Posted by kazetsukai

Two, if you want to do anything significant with 220v off of batteries (shore power is simple) like I am, those batteries need to be enough to push the required amperage. A mere 10A * 220V = 2200W. 2200W @ 12V is 183A. 2200W @ 24V is 91A. 2200W @ 48V is 45A, and so on. On a 12V system, you'll simply destroy any kind of AGM/lead acid battery array that isn't prohibitively large and heavy. Plan for lithium.

I'm already planning for Lithium, a 24v battery system, though I'm still weighing pros and cons for various battery packs. LiFePo4's are pretty much drop-in replacements for AGMs (As long as you have a good charger/inverter, as the profile is slightly different), they're safe, and their charge-cycle lifetime is awesome, but they're more expensive than used EV packs. Even cheap DIY prismatic battery packs cost about $600-700 for 12v 100Ah. And I want like 400-500Ah @24v. That's a lot of thousand-dollar-batteries.

Originally Posted by kazetsukai

I went with Tesla batteries, which _each_ at 24V will push 250A without any cooling, and upwards of 1000A when water cooled. They're also cheap, but have drawbacks. One, I say 24V, but they're on the "lower" 24V spectrum. They're each a total of 444 18650-like lithium cells in 6s74p configuration, which brings their voltage range from 19V to 25.2V. The 24V range for AGM/Lead Acid is 21V-28V, which means you have to carefully select charging equipment, and as your voltage is on average lower you'll be pushing more amps. More amps = larger wires and waste.

I can't stress enough that without the right batteries any venture into high current AC (beyond 2000W draw) will be completely fruitless, and probably dangerous. I'll post info about my inverter later today.

My issue with used EV packs is that their voltage isn't quite right for non-EV purposes, and they're a bit fiddly and a little dangerous. As you outlined, Tesla packs run a couple of volts lower than normal 24v, so I'd need an inverter that can be configured to draw down a bit lower than normal to get the full battery bank capacity. I would rather have the ability to use my entier bank's capacity in an extreme situation, than be forced to leave that last 25-30% in the bank.

My inverters (I'm looking at using two or three) will be very close to the battery bank to minimize losses.

[kazetsukai]

Originally Posted by Drew Bru

We'd considered selling directly to a flipper, too, who'd been doing McMansions in our neighborhood but we would have gotten significantly less money, even factoring in the realtor's commission. Talk to the developer to get a feel for the market and to gauge their interest, but also talk to a realtor. See what the numbers look like.

Yeah.... ugh. I almost don't even want to think about it with all the rest on my plate.

Originally Posted by Drew Bru

As far as the shower pan, would it be possible to sink a fiberglass pan an inch or so and put a removable (slatted teak maybe?) floor panel to bridge the shower area? Not trying to talk you out of your custom shower pan, just throwing out ideas.

This was precisely the plan. I have a 42"x42" pan sitting on my deck right now. I could cut it down a bit, put slatted teak over it. But the key is how the teak would rest on the pan. I can't think of anything that wouldn't put tremendous wear on the pan itself. Perhaps I could coat the pan in something, but what specifically I have a hard time with. Maybe epoxy over it several layers?


Copper seemed easier by comparison. Fork over the cash and get it fabricated to spec, slatted teak overtop, done. I'd put a drain in each corner to negate/minimize problems with drainage.

Originally Posted by Drew Bru

You'll need to line up a place to park this bus if you're not planning on being mobile, esp. if you intend to keep the hens.

I feel I should have this arrangement in place before even putting the house on the market. I'm considering building another bus, or tiny house trailer right after moving out.

Originally Posted by Drew Bru

The logistics are completely overwhelming, I totally understand that. I'd make a couple punch lists of things to address (one for the bus, one for the home) and start knocking things off. It'll help clarify your path forward and keep your head out of the clouds and allow you to see what's realistic and what's pie-in-the-sky.

Thank you, this is also good advice. I am one of those types that keeps myself locked on the 5 year mark of a 5 year plan. Where we are now, where I want to be, then trace how to get there. The mark adjusts slightly quite frequently, so I find myself retracing the whole path alot. While I'm capable of identifying my next immediate steps, I am just not very good at dealing with concerns at point-blank range. Maybe I could organize my thoughts by laying out the immediate next steps, this seemed to help alot with the salvage inspection.

[kazetsukai]

Originally Posted by synestine

I'm hoping to not need much AC, as we're planning on doing a lot of boondocking, are not above chasing nice weather, and I'm aware of how energy intense it is, but with the way the weather's going, we may need it to handle the "freak" heat wave or "storm of the century"... And both of us can't sleep if the temperature gets too warm.

I'm building my system so that, barring 3 days of overcast, I have no problems running a split in the dead heat of summer. Seems like a low bar to clear, compared to the dryer I'm hoping to run at least.

Originally Posted by synestine

My issue with used EV packs is that their voltage isn't quite right for non-EV purposes, and they're a bit fiddly and a little dangerous.

Dangerous? Each individual cell in the pack has a fuse- I'd say the only real danger is its discharge capacity over well over 500A, and the only solution for that is to go from the positive terminal directly to a breaker within inches of the battery. When you use one of these packs like I am, you're not even taxing it with 10% of the expected load of its intended application, 99% of the time. I thought these were dangerous until I owned one. Now, the very idea seems silly. These are extremely well designed.

Originally Posted by synestine

As you outlined, Tesla packs run a couple of volts lower than normal 24v, so I'd need an inverter that can be configured to draw down a bit lower than normal to get the full battery bank capacity.

My inverter will go down to within 1V of its bottom voltage, and alarm at 2V. Don't get me wrong, the lower voltage is a genuine disadvantage for integration because of issues like these, but it isn't insurmountable. From my perspective, its fairly trivial as I am greatly limiting what I run off of AC.

Originally Posted by synestine

I would rather have the ability to use my entier bank's capacity in an extreme situation, than be forced to leave that last 25-30% in the bank.

Its not worth it from my point of view... I'd shut my inverter off. I keep my batteries between 40%-90% charged. But not going full or empty, I'm increasing the number of cycles by an order of magnitude.


Even considering the emergency scenarios, my 24V inverter has run on as low as 19V. I consider the AC side of my electrical non-critical, I would never put anything that wasn't a luxury on AC. Water heater, DC. Fridge, DC. Lights, DC. Routers/network, DC. Automation, DC. Audio, DC. I run laptops, the power bricks are AC but I'll also buy DC equivalents.



Its the DC side I want to be absolutely rock-solid reliable and so far that looks to be the case.

Originally Posted by synestine

My inverters (I'm looking at using two or three) will be very close to the battery bank to minimize losses.

Mine is 5 feet? Ish? Away. I think the losses will be minimal- my inverter is colocated with the bus bars, not the bank. I intend to scale-out with 4-8 packs and keep the current draw minimal... And I'm not even using 1/0 wire from the packs- it doesn't make sense to me. If each pack uses 2 AWG to the bus bar, I can run 4/0 the 1.5' to the inverter and be just fine. I don't intent for any pack to ever be pushing more than 100A-150A, even with the most extreme load going.

[synestine]

Originally Posted by kazetsukai

I'm building my system so that, barring 3 days of overcast, I have no problems running a split in the dead heat of summer. Seems like a low bar to clear, compared to the dryer I'm hoping to run at least.

Are you looking into an RV or tiny apartment washer/dryer unit or a bigger, residential dryer?

Originally Posted by kazetsukai

Dangerous? Each individual cell in the pack has a fuse- I'd say the only real danger is its discharge capacity over well over 500A, and the only solution for that is to go from the positive terminal directly to a breaker within inches of the battery. When you use one of these packs like I am, you're not even taxing it with 10% of the expected load of its intended application, 99% of the time. I thought these were dangerous until I owned one. Now, the very idea seems silly. These are extremely well designed.

I mean from thermal run-away or puncture. 18650s will burn on their own if abused. I'm not saying you're going to do that, but it is a risk. I'm curious, do these packs come with a BMS? Are you monitoring cells and SoC balance? I don't think you'll have much issue with them falling out of balance with the loads you're talking about, but it can happen over time, especially with used packs. I'd just hate to ruin one because I drove a cell into the ground.

Originally Posted by kazetsukai

My inverter will go down to within 1V of its bottom voltage, and alarm at 2V. Don't get me wrong, the lower voltage is a genuine disadvantage for integration because of issues like these, but it isn't insurmountable. From my perspective, its fairly trivial as I am greatly limiting what I run off of AC.

Its not worth it from my point of view... I'd shut my inverter off. I keep my batteries between 40%-90% charged. But not going full or empty, I'm increasing the number of cycles by an order of magnitude.

That's a nice inverter. I didn't think it was insurmountable, or I'd have abandoned the idea already. I'm trying to maximize capabilities and balance other requirements (one of which is getting everything hooked to my home automation system, so they can be monitored, and alerts can be triggered and action taken automatically)

Also from the research I've done, Lithium batteries seem to like being around 50% SoC, so running them at between 80-20% or better yet 75-25% gives yields the most charge cycles. And if your cells are bottom balanced, you shouldn't be in danger of running any one cell down too much.

Originally Posted by kazetsukai

Even considering the emergency scenarios, my 24V inverter has run on as low as 19V. I consider the AC side of my electrical non-critical, I would never put anything that wasn't a luxury on AC. Water heater, DC. Fridge, DC. Lights, DC. Routers/network, DC. Automation, DC. Audio, DC. I run laptops, the power bricks are AC but I'll also buy DC equivalents.

Its the DC side I want to be absolutely rock-solid reliable and so far that looks to be the case.

Depending on my fridge choice, my A/C side will also be non-critical. I've been trying to find a decent size DC fridge that doesn't cost the same as an old Honda Civic (I refuse to use a gas fridge), but may have to go with an apartment fridge if I can find the right one (something that doesn't radiate heat from all sides) and add extra insulation. If I go that route I'll probably have a separate inverter to run only the fridge so we can shut off the main one when necessary.

I'm also looking for rock-solid stability as well. It keeps the wife happy, and you know what they say.

-S

[kazetsukai]

Originally Posted by synestine

Are you looking into an RV or tiny apartment washer/dryer unit or a bigger, residential dryer?

I've always sized my system to be residential dryer loads + 2000W. I've basically already proven the inverter will run the dryer by putting 1900W on each leg, the problem is whether it will do 3000W on each leg. If this 8kW will not, I'll go for the 48V, 15kW unit, I've already seen it do 14kW in tests.

Originally Posted by synestine

I mean from thermal run-away or puncture. 18650s will burn on their own if abused. I'm not saying you're going to do that, but it is a risk. I'm curious, do these packs come with a BMS? Are you monitoring cells and SoC balance? I don't think you'll have much issue with them falling out of balance with the loads you're talking about, but it can happen over time, especially with used packs. I'd just hate to ruin one because I drove a cell into the ground.

The pack came with an adapter to common LiPo cell balancer leads, so from day one I put a cell balancer on the pack. It was way, way out of balance when it got here- .4V IIRC. Took the tiny balancer almost a week to bring it within 0.01V. The balancer has been running constantly for a year at least now, keeping each cell in the pack within 0.02V of each other.

Originally Posted by synestine

That's a nice inverter. I didn't think it was insurmountable, or I'd have abandoned the idea already. I'm trying to maximize capabilities and balance other requirements (one of which is getting everything hooked to my home automation system, so they can be monitored, and alerts can be triggered and action taken automatically)

I have more budget than many converters I've seen, but there are definitely limits. The selling point to me has always been kWh/$ and these packs are at the top of the list.

I like the Victron Battery protectors- apparently you can configure them via bluetooth like the charge controllers. Fully adjustable cutoff voltages, a lead to control the disconnect via relay, and an integrated relay to control other devices all in one.

Originally Posted by synestine

Depending on my fridge choice, my A/C side will also be non-critical. I've been trying to find a decent size DC fridge that doesn't cost the same as an old Honda Civic (I refuse to use a gas fridge), but may have to go with an apartment fridge if I can find the right one (something that doesn't radiate heat from all sides) and add extra insulation.

So yeah, I may temporarily use an AC fridge. Long term, I'd like one or a pair of the Dometic dual zone chest fridge/freezers- they have the lowest energy consumptions I've seen on a DC fridge, I think they may have internal batteries as well as native 12V input ports.

Originally Posted by synestine

I'm also looking for rock-solid stability as well. It keeps the wife happy, and you know what they say.

I'm very fortunate- the only requirements I've gotten from that end of the equation is 100% working facilities of the home. 110VAC (she doesn't care about DC), toilet, kitchen sink, a sink in the bathroom (why we need it in addition to the kitchen sink- *shrug*), shower, bed, etc.

[Drew Bru]

Originally Posted by kazetsukai

Please, elaborate however you can.... A (Natures Head) is my current plan, but I might install a black tank to hedge my bets. Can I go a week without dealing with solid waste? If so, its a no-brainer and I might just not bother

With two of us using the nature's head full time, we empty the pee jug every day and a half to two days. The solids get dumped every 3 to 4 weeks. Easy to install, easy to maintain. No smell, no mess, so easy to dump we changed the solids out at a gas station while the bus was filling and put the bag in their dumpster.

[kazetsukai]

I'm breaking radio silence...


In the last couple months, we gone through some intense family drama and worked on sorting out our finances. We've never been able to make steady pace, its always been busts and booms in terms of progress.


So now, we're staring a big boom in the face. I have roughly 3 months left in the fall real estate market- which boils down to 2 months to make the skoolie livable, during which I'll need to find a place local to park (We intend to keep our jobs for the time being), empty out the house and then 1 month or so left to sell. I taste blood in the water... Should I go for it? For Gold? Or should I deflate that balloon and aim for Spring?



Some big problems I'm facing at the moment:

• Drainage and waste management is my next infrastructure focus. I live in NH so it is important my plumbing is all in the cabin, to keep it from freezing. I've always thought 100 gallons of fresh water is the sweet spot, I'm having trouble fitting that into the kitchen, even combining smaller tanks. 150 in grey seems doable.
• We're also looking at laundry machines. Specifically: traditional, compact, residential washer/dryers. The Bosch 300/500/800 series looks like it will fit nicely in my rig, I just need to size the solar for it. Yeah, I intend to power a residential dryer off grid. Anyone have power usage metrics from the units they have in their rigs? Size/Capacity + Wh per load would be most helpful.
  
  I think I can deal with around 4kWh/load from the dryer if the units' capacities are decent. Not sure what to expect from the washers beyond.... less than the dryer?

[kazetsukai]

Holy cow. I'm suddenly unblocked on almost all my plumbing and drainage, all that's left to arrive is my fresh water tanks. Tomorrow I'm getting the 6 new tires mounted, state inspection and a look-over by a mechanic. Shipping out some of my LED flashers, too. If I can get helpers, I may mount my grey tanks as well.



We figured out the shower, and finished the floor. Have a new divider wall up front that fits perfectly. More and more feeling like a home.

[kazetsukai]

All new tires, and state inspection is done. I was told the guy that does 'em at the Freightliner I went to was a real stickler. Always finds something. Well, not this time apparently. Thanks for remounting my front plate buddy! I was just missing the hardware.



Need insurance....



Grey tanks are in: two tanks, 45 gal each, facing each other and meet at a T.



Used strut channel and 1/2" threaded rod. 6 attachment points, 4 to the bus body and two to strut resting on the chassis where I couldn't get good body mounts.






Air vents on each tank, with 2" drainage entry points on the 3" PVC pipe. The pipe hangs with strapping.

[kazetsukai]

Electrical cabinet rebuilt...




This was primarily to accommodate two new batteries and finally I got another 1000A bus bar for negative. I have a 24V native panel, 12V panel stepped down from 24V, and a smaller 48V panel stepped up from 24V. I took this opportunity to correct some of my hacky wiring. I'm now running four 4/0 cables from the bus bars to the inverter now whereas before I was splitting off one 2 AWG cable from an inline shutoff switch.






The DC side: Most of my electrical consumers are 12V. Lights, speakers, etc. There are a couple 24V appliances (fridges, etc), and one recent addition that is the 48V panel (PoE/cameras). I have 12V subpanels in the front and rear, I prefer them to running a ton of wires all to one place.



The AC side, not much to say here. Split phase, so same as the typical house. I have 220V available for my future mini split and maybe a dryer in the future. My current washer/dryer combo unit is 110V. For now the second phase is largely unused, but I'll run that leg back to the kitchen when its time to wire up there. This system is more or less tested and bulletproof.



One thing I did do was move all the DC off the left side of the cabinet.



My intent here is to run all of my automation wiring here instead, and make room for a second MPPT controller if I choose to get more than 2200W in panels. You can see all this small wiring just above the last shot:



This is _much_ cleaner than it used to be, and gives me good mount points for everything.


Other news.... water tanks all in, will probably either start cranking away at the rest of the kitchen or get into the shower.

[kazetsukai]

Stuff is coming together! Getting help is paying off, the end is in sight! Finally!


The kitchen is getting closed up. Nothing yet picture-worthy, will probably see that stuff tomorrow. I installed my stove:



Test run of that this weekend. I got in meters for AC consumption, as measuring on the DC end for my inverter just isn't practical anymore:



So one of the things that I find unique in my build: The electrical cabinet is a place for my DC wiring, my batteries, the AC breaker panel and.... my automation equipment.



To recap, instead of running buttons/switches inline with my lights, or a main switch panel for my appliances, I run all DC wire- switches, appliance, lighting, etc- back to the cabinet. That's the thick bundle you see above. A pair of relay controllers drives everything, a computer taking commands from the switches. This is so I can control anything in the vehicle from the driver seat.


One of the big items on the automation list was a computer I could power via 12V. I had been using Raspberry Pi 3's, but SD cards don't seem reliable. Anyway, this last week I got the panels' touch screen monitor in place:



This was my first shot at setting up a Linux rig completely driven by touch (no keyboard or mouse). I have to say while it needs a little polish, I'm very happy with the result. Combined with my speakers I have very nice audio while I'm out there working.


Finally, I installed the security system. I had the choice between an awful analog backup camera kit, four cameras, or a completely digital security camera kit for around $50 difference in price. I can see every angle of the vehicle with a 1080p feed from each view.



That, and I can watch the cameras from anywhere via the bus' computer system. I'm considering putting a camera underbody to watch for problems on the road.


But the biggest advancement has been the diminishing number of raw framed areas- My bathroom is completely finished, The rest of the kitchen is getting finished over tomorrow, and I may see the shower up this weekend. The end is in sight! This saga is wrapping up!

[PNW_Steve]

Looking great!

One item that struck me was the drain plumbing for the waste tanks.

Your setup looks awfully close to what I have been working on in my travel trailer.

The long run of plumbing from the "T" to the drain cap has lots of leverage on the tank connection and the way it is hung allowed a little up and down motion. This has resulted in both tanks cracking where the drain plumbing connects.

Fortunately the tanks in mine are ABS and are fairly easy to patch.

Now I am working on a better way to support it so it doesn't crack again.

[MAH2]

Why don’t you use a propane dryer?

[kazetsukai]

Originally Posted by PNW_Steve

The long run of plumbing from the "T" to the drain cap has lots of leverage on the tank connection and the way it is hung allowed a little up and down motion. This has resulted in both tanks cracking where the drain plumbing connects.

Fortunately the tanks in mine are ABS and are fairly easy to patch.

Now I am working on a better way to support it so it doesn't crack again.

Thank you for this comment. I would have been blindsided by a similar problem. My solution to this problem I may install this weekend, immediately exiting the "T" from the two tanks, I'll cut and reconnect my drain line with:



I have two of these, together should provide enough flex/play to keep the leverage from breaking anything. Additionally, I'm going to strap the 3" pipe down as well as up, to eliminate any up/down or side-side play I can.


I just hope they don't leak.

Originally Posted by MAH2

Why don’t you use a propane dryer?

They're Unicorns/$$$


Perhaps an upgrade for later.

[PNW_Steve]

That will work. I had to use one of those in order to put mine back together and it has held up well. No leaks.

[MAH2]

Originally Posted by kazetsukai

They're Unicorns/$$$


Perhaps an upgrade for later.

That's one of the few home appliances that would work well. What's your budget, you can buy a cheap one for $500 from home depot that's 29" wide. What size is the electric one that you want to use?

[kazetsukai]

Originally Posted by MAH2

That's one of the few home appliances that would work well. What's your budget, you can buy a cheap one for $500 from home depot that's 29" wide. What size is the electric one that you want to use?

The Edgestar Combo unit I bought off Craigslist (CWD1510S) is 23.5"x23.5". It would have to stack. When I say "unicorn", I mean compact + propane. I'm going to get hot water running end of today so I can finally test the power usage of the combo unit I have (110V).



I don't really have a budget for this right now anymore, but I'm thinking as a later upgrade of running a 220V condensing electric dryer (Bosch 300 series) above my washer/dryer combo. Having to run it every couple days isn't really that bad.

[kazetsukai]

Originally Posted by kazetsukai

I'm going to get hot water running end of today so I can finally test the power usage of the combo unit I have (110V).

I just got hot water out the tap.... so simple, yet...


Man. That's something else. This heater is awesome.