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Hi guys,

I bought a control board from Paul Holmes a few months ago. I now have the budget to move forward on it. I picked up a Leaf motor from the local wrecking yard which I will be pairing to the control board. I'll use this thread to document the process and solicit advice.

I just got a box of components from Mouser, so the first task will be to solder up the control board.





 

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Nice. Do you have a ballpark price of expenses so far? What is your electronics experience level? Thanks for starting this thread.

I am trying to decide whether to buy tested populated board or go DIY.

Harold
 

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Nice. Do you have a ballpark price of expenses so far? What is your electronics experience level? Thanks for starting this thread.

I am trying to decide whether to buy tested populated board or go DIY.

Harold
The bare board was $60 and the components were about $200.

I think Paul sells the populated board for about $300 so that's a ridiculous deal...I'll spend way more on the time it takes to solder it up, even if I account my time at minimum wage. I got the unpopulated board because I want the experience of soldering up a bunch of surface mount stuff. He used big 1206 components for most of the stuff, so it's a good beginner's project.
 

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Thank you. According to his website, a completed board and tested good is $350.00 + S&H. Still probably a good deal.
 

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I plan to convert a suzuki SJ410
some news ?
what voltages are you choosing on battery side ?
Do you think engine from Prius also be good ?
Now I am think what controller use , P&S or Huebner
 

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I put further development of my leaf motor and Pauls controler on hold. I think i have to try and rebuild power section again. I think i have too much EMI from DC rails. I have to make them overlap. Maybe i will just use flat copper sheet with isolator spacers. Also i will use different shielded encoder cable.

If you are interested here is my progress thus far.
I made it up to 100Vdc but beyond that motor gets its own mind...
https://leafdriveblog.wordpress.com/

Edit: I will not go back to building poswer sections. I will just use existing one from Volt, Prius, Leaf etc...
I have success with Lebowski board which uses the same chip as Pauls.
https://leafdriveblog.wordpress.com/2019/04/05/single-lebowski-ampera-inverter/

Arber
 

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Are the Paul holmes leaf inverters still available? It seems that the website is no longer operational.
 

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Are the Paul holmes leaf inverters still available? It seems that the website is no longer operational.
Paul had his whole life stolen (was moving and the moving truck was stolen with all his things).

I think I heard somewhere that he wasn't much interested in doing inverters for people anymore.

The new meta for cheap DIY EVs is to buy a Prius Gen 2, Gen 3, Lexus GS450H, Nissan Leaf, maybe some other Toyota model inverters, then a controller to hijack them, and use those.

Guys are finding Gen 2 and Gen 3 Prius controllers for like $40. The Gen 3 can handle about 680 horsepower. More than anyone needs. They also have a built-in DC-DC 12v converter, one of the motor controllers can be repurposed as a charger (software is being written right now), and an A/C inverter too. Bulletproof and they soft fail when you overheat, abuse, or tell them to do something stupid.

You can buy Johannes' inverter controllers for around $500 (380 euro) on OpenInverter.org (also forums there). Or Damien's for around the same price on EVBMW.com.

Damien used to offer even cheaper ones but we are frustrating and fickle to deal with, so I think prices go up to make it worth his time and make sure he's not losing money. For example a Gen 2 board used to be $30 and you could flesh it out with components for $70. Plus a few extras needed, easily under $50. Meaning you could have a 500+HP inverter with custom controller for under $200 in many cases.
 

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Paul had his whole life stolen (was moving and the moving truck was stolen with all his things).

I think I heard somewhere that he wasn't much interested in doing inverters for people anymore.

The new meta for cheap DIY EVs is to buy a Prius Gen 2, Gen 3, Lexus GS450H, Nissan Leaf, maybe some other Toyota model inverters, then a controller to hijack them, and use those.

Guys are finding Gen 2 and Gen 3 Prius controllers for like $40. The Gen 3 can handle about 680 horsepower. More than anyone needs. They also have a built-in DC-DC 12v converter, one of the motor controllers can be repurposed as a charger (software is being written right now), and an A/C inverter too. Bulletproof and they soft fail when you overheat, abuse, or tell them to do something stupid.

You can buy Johannes' inverter controllers for around $500 (380 euro) on OpenInverter.org (also forums there). Or Damien's for around the same price on EVBMW.com.

Damien used to offer even cheaper ones but we are frustrating and fickle to deal with, so I think prices go up to make it worth his time and make sure he's not losing money. For example a Gen 2 board used to be $30 and you could flesh it out with components for $70. Plus a few extras needed, easily under $50. Meaning you could have a 500+HP inverter with custom controller for under $200 in many cases.
Wow...I have no idea how to do any of that, but I really appreciate the information. It looks like I have even more research to do. I'm beginning to feel like I've bitten off a bit more than I can chew.
 

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I was incorrect.

Damien sells a Prius Gen 3 kit for 350 eur (~$500). He sells just the partially-filled board (which needs a few extra components) for only 120 euro. You can definitely cheap out there if you can solder a little bit.

Both of the kit versions (Johannes' Gen 2 and Damien's Gen 3) should be pretty much plug and play. You literally just unplug the original board, plug the replacement in, and you're ready to start connecting the gas pedal, brake pedal, etc.

As a general build plan:
1 - Figure out your budget and general build plan. Make sure it makes sense.
2 - Do your motor and mechanical adaption first. Motor is usually cheap and all this mechanical work tends to take longer than anyone expects.
3 - Get your motor spinning from your speed controller on a temp setup, make sure it's all good. These options tend to change as time goes on, but motors are blind to what you use.
4 - Buy and mount your batteries. These prices change constantly, generally downward, and are the most expensive part of the build.
5 - Finish up your brakes and accessories.

Know that 90% of car projects never finish or get abandoned. So, presume those are your odds and:
A - Minimize the wasted money if you walk away.
B - Maximize your odds of finishing by proceeding in a sensible direction.
 

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Hey Matt, do you offer tutorials? I no desire to walk away nor do I want to waste money, but I am a bit overwhelmed with all of the different choices. If you offer a class or private instructionals of some sort I would love to take part. I understand my shortcomings and need a pros guidance
 

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Hey Matt, do you offer tutorials?
My advice is worth less than you've already paid for it.

Best I can do is steer you in the right direction.

If you offer a class or private instructionals of some sort I would love to take part. I understand my shortcomings and need a pros guidance
If you fly to New Ireland Electric (in Ireland), they host monthy DIY EV workshops for $1000 for the weekend. I'm not sure how many they're still doing with Covid now.

They're probably the only ones.

No point in jumping in with both feet. Start reading on other's projects, note the recency of them, tech and the popular way to go changes over time.

Find a car worth converting. You'll spend or save most of your money by making a smart choices here.

There isn't that much to know, you already know most of it.
 

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Discussion Starter #15
Are the Paul holmes leaf inverters still available? It seems that the website is no longer operational.
I do still have my board (and stuff to populate it, but I never did get to it). I ended up buying a Scott Drive SD300 so I'm not going to use this board.

Really sad to hear about Paul's stuff being stolen. He seems like a real topnotch guy.
 
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