openinverter forum

Hi all,
I think i found a small error on the V6 board.

The diode D1 needs to be backward ( ie the cathode of the diode needs to be on the side where the + is marked)

Picture of a warking board atatched

The other way arround doesn't work ( diode is blocking the 12V comming from Conn6)

Yes true, I found out the same when testing the boards. All boards I ship have the diode corrected.

Hi all,

Would boost mode charging be possible with the Tesla SDU drop-in boards?
Like described here:
https://openinverter.org/wiki/Battery_Charging

Yes should work like with any other drive train. You just need to route your HV DC into the inverter. Please let us know how it goes

Thanks. I will let you know as soon as I've tried. It will take some time though, as I am just at the beginning of this conversion project.
If all goes well, I will receive a Tesla Model S front drive unit this Friday. Then I will pre-order the logic board.

I am putting together my own battery of recycled 18650 cells that I am collecting and testing at the moment. It is good to know that I'll have an option to charge it when it's finished. However there's a lot of work to do before that.

Hi,

So I already have to buy a bridge rectifier for boost mode charging. Could I use it to power my Tesla SDU from the mains, just for low load testing? I can imagine that the incontinuous voltage is not ideal, but do I risk destroying anything (assuming that I dont electrocute myself and use some sort of precharge circuit).
This could be easier than buying a bunch of batteries for testing. The battery I am building for my project is far from ready.

I assume mains is 240 where you are?
You will want a filter capacitor (maybe 2200uf or so) unless you have 3 phase available. Apparently 3 phase rectifies to a nearly smooth DC output. I'm not sure what the resulting DC voltage is though, probably check before connecting to it.

-Isaac

The ”powestage” connector in the open source logic board is a couple of mm thicker than the one in the original teslaboars. It makes it difficult to fit.

oh not good, must have sourced the wrong part. Sorry about the trouble, will fix it asap

If by thicker you mean longer then that's not a big problem. This problem was previously highlighted in the support thread. This is the actual connector tesla use : https://www.mouser.co.uk/ProductDetail/200-CES11201LD

Another question about buck/boost mode charging: Considering a fairly common 96s lithium pack, battery voltage would be between ~288V and ~384V. Using just 320VDC rectified mains as a power supply would not be very convenient right? It would be too high for boost mode, but too low for buck mode.
Any recommendations on how to enable buck, or boost mode charging of a 96s pack with a simple(/cheap) power supply?

You could use a voltage doubling rectifier to rectify mains into a higher voltage, and then buck down from that.

Then I would send 2x320V=640VDC into the Tesla inverter. Wouldn't that be dangerous?

Jelle IV wrote: ↑Mon Sep 14, 2020 11:17 am Then I would send 2x320V=640VDC into the Tesla inverter. Wouldn't that be dangerous?

Yes, the IGBTs are rated for 600V or 650V - to little anyway.
Those 96S packs are a bit problematic in that respect but then they only reach < 320V below 10% SoC.