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LOL. Is 'blah blah blah' an official term for 'safe and by the book'? 馃槀馃槀馃槀
No, more, same routine any time you look at paralleling power supplies. If they're not isolated, it probably won't work, so it depends on the design.

I dont need a full refill. Just a 2k or so top off.
Oh good. Bring a tow rope anyway.

What's your profession btw? You are knowledgeable and I'm curious is it's from the hobby, or life.
Nothing electrical related. I had 2 years worth of electrical engineer education, but it's not the direction I went in. Gives me a decent base enough to dabble but not enough to solve actual problems or have any value. I volunteer a lot at the local makerspace, one of my passions is removing barriers to curiosity so that people who might want to try something can get their foot in the door and try a new medium without being burdened by what most people insist is the minimum entry level. Woodworking, electronics, welding, etc.

This offers a very nice increase in torque/voltage constants over the ME1115 and also allows provides regen ability which will SLIGHTLY increase range but more importantly allows us to have a braking system!!!! This is critical since we cut out the rotor and caliper from the donor. :)
Regen on a tracked vehicle in snow is going to get you pretty much nothing for range increase.

Which is good because, don't expect regen to be there. Can you put the rotor and caliper back in time? 2 is 1 and 1 is none. She'll need to drive it like there's no brake.

This new motor is now rated for 99ft.lbs of torque which allows us to run below max load on the motor and still meet our goal of 60ft.lbs.
Good news, your motor is probably rated at 30'c or somesuch. You'll be in -20'C, a 50' difference, you can probably double or triple what you demand of your motor without making it grouchy.

Bad news, your batteries are not going to appreciate that weather. On a one-off trip, I'd almost just say pack them with styrofoam and leave the sled indoors before the trip, they might stay warm enough to not be a concern. You're going to lose a lot of range.
 

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Discussion Starter · #22 ·
Post 4? 2 days until deadline
I can't keep up anymore. Day after day after day until 2am. Not really sure the order of things anymore so I guess we can talk about the 12v system? starting tomorrow I will just be posting up to date posts.

Anyway. We need 12v to run the controller, 12v valves for the coolant system, and the water heater is a dual element 600w 12v, some need a few 12v circuits for the build. Since 96v to 12v converters are expensive around the 1kw range we elected to go with a 300w dc/dc system tied to a small, 12v, lithium bank. I actually used a solar charge controller to keep the raw incoming voltage from frying the bank.

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4, K2, packs from batteryhookup.com.

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Oh yeah! There were 2 "near death" experiences during this build. I will share those stories soon.

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Night all.
 

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Discussion Starter · #24 ·
Couple more images for fun!


3d printed a box to hold 2 of the 48v packs together and hide the bms wires once the lid is on. 96v, 12s.
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Nasty mess right now, but heres the chaincase, motor, part of the thermal system including the heater.
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Due to time we ended up with braided hose going to the batteries. :/ spent days 3d printing custom adaptors, but failed out pressure and vibration tests. :/

We have a total of 8 12v valves to allow full control of temperature in each pack, motor, radiator, heater, etc.
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Discussion Starter · #25 ·
Post 5.

Good day! 130am ripped around the lake! 1 of 3 BMS's are offline though, but we honestly didnt realize until climbing a steep hill. Coolant pump has air in the lines and is levitating, no flow, but It was still fun!

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Mate, this is one of the most riveting, most real time posts I've seen in a long time.

I wish I could not you a beer for the near real time seat of the pants reading this is.

I think best you can do is upload it to YouTube and plop a link here, there might be an Embed video button and we can watch the YouTube vid from here?
 

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Discussion Starter · #28 ·
Mate, this is one of the most riveting, most real time posts I've seen in a long time.

I wish I could not you a beer for the near real time seat of the pants reading this is.

I think best you can do is upload it to YouTube and plop a link here, there might be an Embed video button and we can watch the YouTube vid from here?
馃槀馃槀馃槀 thank you for the comment! I'm glad somone is getting a kick out of this, because its KILLING me. Almost 3am local time right now and I need to be at work at 7am, so I will upload this weekend. Tomorrow after work is my last day to complete the project! We are heading north for the event out of town on friday....

Cheers mate! Im cracking a beer right now and celebrate with ya.
 

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Discussion Starter · #30 ·
Post 6 or7? The deadline

Ladies. Shes done.

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The DC/DC 96/12v failed on us so we are limited to a TINY amount of 12v storage to run pumps, heaters, valves, the kelly, etc. Not ideal.
Also the 12v pump didnt have about head pressure to overcome the air trapped throughout the system, so I asses a 110v water pump with A LOT more lift and flow That I had laying around anyway for my aquarium. Just threw this in series with the other pump since the original pump is BURRIED. Added a wild amount of flow and helped us purge the air from every book and cranny. We wont run this pump unless the motor is overheating or a battery is freezing.

Hood Automotive tire Motor vehicle Automotive lighting Automotive fuel system


Also remounted the gas tank (crazy story there!!!) And cut a hole in the face to house the 12v batteries and 110v inverter we added for the upgraded water pump.


Our hillbilly replacement charger setup came in today. All attempts at a clean, polished. And safe build went out the window these last couple of days. What do you think of this setup?... so well done.. 馃槀

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2, 1000w. 110v as to 48v dc converters zip ties together (overclocked a bit to 1200w each), then 2 1500w boost converters bringing that up from 48v to 96v. All stuffed into a very safe Tupperware container.

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Took some neat videos. Will upload those after the weekend!

Half day of work tomorrow. Heading north at noon.

Cheers my friends!
 

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Ladies. Shes done.
slow clap

Magnificent.

For all the rest of us dicking away for several years on a build, you go and get it done soup-to-nuts in a week.

The DC/DC 96/12v failed on us so we are limited to a TINY amount of 12v storage to run pumps, heaters, valves, the kelly, etc. Not ideal.
If you want an even stupider alternative, just tap the batteries at 12v and rely on the BMS to balance out the difference from the cells you're stealing from. Will work in a pinch.

Added a wild amount of flow and helped us purge the air from every book and cranny.
If it works it works.

What do you think of this setup?
Temporary test setups are perfectly acceptable.

You're taking it for a weekend of testing.

Sounds good to me.

All stuffed into a very safe Tupperware container.
... and the problem could be hardware, software, fuckin' Tupperware for all you know, all you know is "Charger no work". /Ernie Cline.

It's not even Tupperware, it's Walmart Gladware about as thick as hardened Saran wrap. One bump and she's shattered.

...

I wish you the best of luck. Hopefully your wife doesn't roll the damned thing.

Can't wait to see what shenanigans you got up to.
 
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