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Pics of the compression fixture. I made the end plates from some 1/2", 9 ply Birch plywood from Home Depot. This is the experimental version, once I am convinced I have everything figured out I will rebuild it using 1/2" Baltic Birch plywood I have. The end plates are 12" high, because I didn't...

If you notice, almost 100% of my posts have been edited. I immediately go back and reread them. I don't know why typos only show up after I click the Post Reply button. I think it is the site software. Yah, that's my story.

Got results from my research to report. I found a stackup of McMaster Carr spring washers that will do what I think is needed. My criteria is to limit force at 100% SOC to 15 PSI. I have read that these cells expand between 0.7mm to 0.8mm from 0% to 100% SOC. I am working with 4 cell stacks in...

You will be amazed how easy it is going back as an adult. Old enough to not be afraid to do the work. No day job to have to work around. No wife and kids. I had all 3 of those when I got my BSEE. https://www.unlv.edu/degree/bse-electrical-engineering When I went to school, I was surrounded by...

I have been looking for a tiny inverter based microwave for my Van RV build and Panasonic has this 0.8 CuFt, 950W beauty. Rotating glass turntable for even heating and only requires 1200W to operate. https://shop.panasonic.com/support-only/NN-SD372S.html $140 from Staples...

60 Hz transformers have some high frequency filtering capability. Not enough to fix what is wrong with modified sine wave inverters, but some. Pretty much all modern inverters are high frequency as in they use high frequency PWM modulation to turn DC into AC. The cheapskates do it by stepping...

I like to keep an open mind, but not so open my brains fall out.

A power supply comes in 3 flavors. No current limiting, you overload it and it burns up. Current limiting by turning off the output until the load is removed. Constant voltage output up to max current, then constant current from then on. As you lower the load impedance the output voltage...

I got an idea. How about a catapult held down by a very flammable rope. Battery pack catches fire, launches them in an arc aimed at the backyard pool. This sounds like a product we should be able to buy from Acme. http://www.jamesfuqua.com/lawyers/jokes/coyote-acme.shtml

Now we are getting into the fun part. Research, collecting data, being scientific. I will even wear a lab coat and carry a clipboard while I am doing this. Who's with me?

On the subject of grounding. Victron has this statement on their MPPT FAQ page. https://www.victronenergy.com/live/drafts:mppt_faq I agree with the reasoning behind connecting DC negative to chassis ground at a single point. Avoiding ground currents (ground loops?) makes sense. You don't want...

The smell is unmistakable if parts got burnt.

An architect, artist and an engineer were discussing if it is better to spend time with a wife or a mistress. The architect said he enjoyed time with his wife, building a solid foundation for an enduring relationship. The artist said he enjoyed time with his mistress, because of the passion...

USA power is center tapped 230VAC. The center tap is the neutral wire which is connected to earth and safety ground at the point it enters a building (main circuit breaker). The 120VAC in our wall outlets is from either of the two hot wires to neutral. 230 (for dryers and air conditioners) is...

This is what I am using for my 12V control panel. The safety toggle switch is used as the On/Off control and you have to press the start button to latch in the power relay to the 24V to 12V DC-DC converter. I am using a 24V automotive relay instead of the 12V relay that came with the control...

If you want a more accurate method. Get a piece of unistrut and mount a socket extension in the middle. Mount an eye bolt at each end of the unistrut (the same distance from the middle to each end). Mount the socket wrench in the vise and plug the socket extension into the wrench. Hang weight...

Agreed and to make a long story even longer. In general we don't want to use the vehicle chassis to carry current. Doing so leads to corrosion and weird electrical behavior. To ensure this can't happen we use a negative bus system and only connect that negative bus to chassis ground at a single...

Serves double duty as a fire detector too.

Here is what my battery pack will look like including the compression frames. The two 4 cell sets are completely independent except for cabling between them. Each cell pack will mounted on a set of these rubber shock mounts to keep them from bouncing around inside the battery compartment...

How dare you interrupt our digression into a bit of Tesla worship by discussing the original thread subject! ?

Looks might mean nothing. When the Chinese knock off a product they often make a visual duplicate. I once sent a thermal label printer to a contract manufacture to give us a cost estimate on what it cost our competitor to make. They misunderstood what I wanted and made a visually perfect...

I am putting 7.2 kWh of batteries in my Ford E350 van conversion. They are going to be in a 2 x 4 orientation (24V) when done, just sitting on the bench right now. Building the cell compression frame this weekend. hey

OK, new figures. Assuming 0.9mm is the travel I need to handle from 0 to 100% SOC. I am using 5/16" x 18 TPI threads. 18 TPI is 0.056" per turn. Convert that to mm and I get 1.4224mm per turn or 1 mm = 70% of a turn. I am going to call this 2/3 of a turn since I am not a human protractor. I...

Borrowed a 2000 Newton load washer from work today. 2000 N = 449 lb. Now I have to build the test fixture. And get a lab coat.

The point of the ground wire is to provide a fault clearing path in the event the metal enclosure of an AC powered device gets energized. This can only work if the neutral and ground are electrically connected (bonded) together. This way the circuit breaker will trip. In residential wiring the...

Older low frequency inverters used a square wave generator that was fed into a ferroresonant transformer to filter out harmonic noise and convert the square wave into a sine wave. Ferroresonant transformers have the ability to regulate the line voltage by storing energy in magnetic form within...

And to be clear. The isolated version just means you can leave the output floating (no need to tie ground to the vehicle ground). The positive output is in fact isolated at least as far as protecting your starter battery and alternator are concerned with either version. That is the entire point...

Or just buy an upgrade, continuous duty rated alternator and use a 12V to 24V boost battery charger. Like a Victron Orion TR 12/24-15 Smart Charger. That will draw 30A from the alternator and charge a 24V battery at 15A. It will also protect both your alternator from overload and your battery...

You did the right thing.