Paul & Sabrina's Cheap EV Conversion

[bennelson]

I'll be pulling out the 350 amp disconnects for the 144v testing....

[MPaulHolmes]

Hey, I got new batteries! Ben, I'm glad you are putting in a manual disconnect. I feel better now. hehe.

Oh man, how am I going to crimp those big lugs onto the anderson connector?


175 amp (continuous) Anderson Connector!


Hey, a homemade hex-crimper (sort of hex).


Crimp Acknowledged!


Hey, my emergency disconnect "cord". hehe. It's parachute cord that has a breaking strength of like 500 or 600 pounds, even though it's really thin. I bought 6000 feet of it several years ago to make a net for a solar balloon that I was going to make and fly to Montana, but my wife wouldn't let me. I guess something could have gone terribly wrong, but I still want to try it. I sent one up at noon and it came down around 5 pm (when the sun set) in Spokane. So that sucker went like 300 miles in 5 hours! A student in the math class left her number, so the guy that found it called her. Man! I think it got in the jet stream that goes east at around 30,000 feet up. But I digress...


Wow! I did it! ya! Well, I had to get a nut from Lowe's, and I still haven't attached it to the battery yet. I'll do that tomorrow.

[Intrigued]

IT'S ALIVE!!!... or well, like, IT'S SPRING!!!... and stopped snowing... for the most part...

Around here we have some of our biggest snows this time of year. They don't stay on very long, but those big wet snowflakes can really come down fast. But I digress too....

I love the "engine-uity" on the Anderson disconnect! I agree with your wife on the solar balloon... maybe you could send up a robot you created first, that could either drop sandbags or shoot smaller balloons to keep the correct altitude. You know how those pesky jets are when they get stuff in the engines, and the air at 30k isn't very breathable for that matter.

I also love the idea on the crimper, LOL!!! That's about all that those bolt cutters are good for, unless you actually got one with real metal jaws! Funny thing is, if that was the yellow-handled cutters I saw in the first picture, those look like they have some kind of crimping mechanism on the handle side of the fulcrum. Either that, or your kids have been playing with the dremel tool again...

[MPaulHolmes]

Holy cow! You are right! They do have a crimper! I never knew what that thing was for! Man do I feel stupid!

[Intrigued]

Hey, don't feel stupid yet! The questions remain as to whether the built-in crimper 1) actually has anything anywhere close to what you need, and 2) has good enough metal to actually make more than 2 (okay... 3 on a good day) crimps to begin with!

(I have a pair of bolt cutters that already looks like what you did to yours, but it got that way from trying to cut open a lock. Not one of those case-hardened ones, either... After that I found out you could soften the metal you want to cut by using a propane torch running on MAPP gas...)

ANYway.... if it actually does work, you can now do two crimps at once!

[bennelson]

Paul, I actually think your home-built crimper is probably better than the yellow handled one anyways. Lots of guys do exactly what you did.

For future reference, you don't have to chop the other wire on the Anderson connector.

If you look inside at the conductor part - where tab a and slot b actually touch, you can see there is a little clip that holds the conductor in there. You can stick a screwdriver in, hold that clip down, and pull the whole cable straight out.

It makes more sense if somebody just shows you.

You can also make a super-duper battery "key" from an Anderson connector by running BOTH cables from one connector to your batteries. Then, make the other cable loop to itself, so that the power goes in side A through the other half of the connector, and goes through the second cable in Side A.

Then, you just pull the whole B side off to disconnect. Take it with you, and nobody can drive the car! I think that it could potentially disconnect a higher amperage that way too because you are disconnecting at 2 points simultaneously. (Not positive on that one, but I think it works that way.)

[MPaulHolmes]

I'm going to install a relay for the pre-charge resistor I think. What's a good relay? I never knew there were such things as relays until 1 week ago. Isn't that sad?

[Intrigued]

LOL!!! You kill me!... with a rusty butter knife, to boot!

For a good, rugged, inexpensive relay that'll last a while and carry just about any short-term current you'd need, go to an auto or tractor parts store and get one of those old Ford tractor starter relays. They're easy to bolt up, difficult to mess up, and I've put several on old lawn mowers I have worked on, and saved a bunch of money!!!

Overkill, possibly. Inexpensive and works, yes.

JMHO...

[Hondo]

I used an old auto fan relay to supply juice to my contactors (they're 48 volt). Has worked great for over 2 years. If you visit your local salvage yard, you can usually get them cheap and they are rated for continous duty.

Hondo

[ev59rag]

Paul,

Hows your Harbor Freight 6 amp chargers? How are they holding up? Do they really switch to trickle mode when it is completely charged? Then how long will it stay trickle before it goes to shut-off?

Sorry for so many questions, I think Im going your direction with my 72 volt system.

Cesar