openinverter forum

Hi All,

I got my 450h spinning! For testing purposes I used a 12V car battery to drive the inverter. Doesn't spin fast, but this is perfect for bench testing (see video below).

One thing, I had the VCU set to DRIVE, but the rpm speed reported by the VCU was a negative value. Did I do something wrong?

Also, what should I do next? I got a battery pack from a Volt, and the DC-DC converter from the Volt as well, so I am thinking that the next goal should be a full voltage test. This probably means that I should build a high voltage junction box? The front face of the Volt battery box seems to have all the components needed for something like this, right (e.g. contactors, pre-charge resistor)? Has anybody directly used this?

Not sure what the HVJB looks like from the volt battery, for a bit of comparison I’ve been using this one from a Gen 1 Prius battery for testing at max 250V for around 6 months now with no issues at all. The pre-charge resistor is around 10Ω which I thought seemed a bit low as precharge was happening at approx 25A but that seems to be well inside the Leaf inverter’s abilities.

It reports negative speed for MG1, as it does spin backwards with the input shaft locked (as compared to MG2).

james@N52E01 wrote: ↑Mon Nov 30, 2020 6:22 am Not sure what the HVJB looks like from the volt battery, for a bit of comparison I’ve been using this one from a Gen 1 Prius battery for testing at max 250V for around 6 months now with no issues at all. 178BB533-1328-4B2A-A75D-722B83BE5031.jpeg
The pre-charge resistor is around 10Ω which I thought seemed a bit low as precharge was happening at approx 25A but that seems to be well inside the Leaf inverter’s abilities.

Thanks, James. Sounds good, I'll see if I can work what I have to something similar.

Are there any resources out there for building a HVJB? I feel like most people here have converged on a design and I'd like to figure out what goes into it and why.

slow67 wrote: ↑Mon Nov 30, 2020 2:06 pm It reports negative speed for MG1, as it does spin backwards with the input shaft locked (as compared to MG2).

Interesting. I seem to remember both MG1 and 2 we reporting negative. The input shaft was not locked.

Well, I got the Gigavac GV242MAB contractors for a pretty good deal, so I can start with that. Any recommendations on where I could get a pre charge resistor? ZeroEV looks pretty good for a 100W resistor.

Should I also get a 400A fuse? Any recommendations on the size wire I should use for the HVJB?

You can get a resistor from mouser or any of the electronics retail places. The recommendation is to have about 200 ohm of and it should handle about 100W of heat dissipation (it's only used for a few seconds each time).

https://eu.mouser.com/ProductDetail/TE- ... 1625999-8/ is a good option for reasonable price.

For fuses you'd want one in about 400A range and for the auxiliary devices you'd want one smaller one as well.

These fuses are cheap to get (few euros each where I'm living) and have high enough DC rating to be suitable. https://www.etifuses.com/pdf/FL-NH.pdf

bobbyj_408 wrote: ↑Wed Dec 02, 2020 7:29 am Any recommendations on where I could get a pre charge resistor? ZeroEV looks pretty good for a 100W resistor.

I personally like ARCOL's Chassis Mount Planar Resistors. High durability, lots of mounting options, and because of the design, excellent heat dissipation. Should last forever. A 200 ohm (5%) 100W version can be found with the part number `LPR100 200R J`. Find the best supplier for price and location by searching on the awesome Octopart database crawler https://octopart.com/search?q=%22LPR100%20200R%20J%22

Cheers!

bobbyj_408 wrote: ↑Wed Dec 02, 2020 7:29 am Any recommendations on where I could get a pre charge resistor? ZeroEV looks pretty good for a 100W resistor.

Water heater element, cheap and commonly available. Or if you have a high voltage cabin heater, you can have it double as the precharge resistor and the precharge relay will double as the heater relay. (One end of the heater connected to the positive from the battery through the relay, other end connected to a IGBT or MOSFET going to the negative rail and a diode to the positive rail.)