openinverter forum

Oh one detail I forgot: at one point when I accelerated the inverter shut off. I thought "oh no, I thought at this rpm the software was bullet proof". Well it is What it was was an overheating inverter gracefully shut down by Japanese engineers. The connector for the coolant pump had come loose! If you take it slowly you can actually drive without circulating coolant. Mind you, the inverter was rather hot!

Update2: charging circuit repaired, basically had to swap out both CAN transceivers. Some transient must have hit them. Time to add some TVS diodes! The trusty 30 year old 74 series chips survived!

Are your batteries in a waterproof box? It's hard to tell from the photos, looks like you've just got a cover over

No, they're not. Protected from spray but you don't want to wade with this car.

I find that really funny that Germany has strict emc requirements (as detailed in your projectsTC cheesewright episode) but then lets you have batteries under the car which are exposed to the elements. Love reading this thread btw Thanks Johu

Yes, some say not all regulation makes obvious sense

Isolation alarm!
The fact that I use a non-isolated charger gives me a free isolation check on every charge. Should the GFCI trip then something is not well. So happened today (and a couple of times before). So what I then do is open the junction box and measure voltage from B- and B+ to chassis. It should normally be balances, like udc/2 in both directions. It was not.
So then I take a 10k resistor and connect it between B+ or B- to chassis GND. Now I would expect any voltage to collapse. But it did not, stayed at 70V. 70V/10kOhm=7mA . Not good.

So then I disconnected the peripherals, namely DC-DC converter and inverter for heating. Problem gone! Reconnected DC-DC. Problem still gone. And also charging works. So something seems funky inside the inverter, will check.

You may wonder why it affects charging? That's because the B- contactor is currently stuck.

At one time during the charge of my Mazda i was dropping evse right and left. At the time i was using EMW charger non isolated. I stripped my car down before i noticed a strange smell when i connected 3phase plug. Mind you that was in 2015 and i didnt have mennekes socket but a normal red DIN 5 pole socket on my car.
It turned out i had a big blob of dirt behind the plug under the wheel well. Dirt got stuck there and when rainimg moisture got next to the pins and gfic dropped the ball. I recommend to check the obvious places for dirt or wettness.

Edit: also i noticed some inverters have a 10Mohm resistors from main caps to the rails. But those are generally low voltage controlers...

Isolation alarm fixed.

Turns out I had too little clearance between HV and GND on that little prototype PCB that you see on the right. Over time and with moisture this has become an issue.

Inspected HV wiring and batteries after the latest incident and all is good. Also freed the negative contactor.

johu wrote: ↑Fri Apr 08, 2022 7:15 pm Also freed the negative contactor.

Did you hit it with a hammer or smack it against something?

Down side is if it stuck once it creates pitting and peaks which can cause sticking alot quicker.

tom91 wrote: ↑Fri Apr 08, 2022 8:03 pm Did you hit it with a hammer or smack it against something?

Down side is if it stuck once it creates pitting and peaks which can cause sticking alot quicker.

Indeed a hammer.
I'll be watching it, I assume it won't be as good as new

Does your power steering remain powered on for a time after the ignition is turned off? I ask because I've been playing with the same rack, and both just using the enable signal or also sending rpm power it up, but removing them doesn't power it back down. I hear the relays click on, but they only seem to click off if I disconnect the 80amp main supply

Edit, it does indeed seem to have a time out, put 12v on the enable then removed it, came back 15 min later and it was off again.

No, it turns right off. Can't tell you why as I never had to fiddle with it. It also turns off immediately when sending 0 rpm

johu wrote: ↑Tue Apr 05, 2022 7:52 pm Isolation alarm fixed.

Turns out I had too little clearance between HV and GND on that little prototype PCB that you see on the right.

I'm interested in your setup. One of the many mandatory requirements where I live. I thought of an Isa shunt between hv and châssis with a tolerance (cut-off voltage around 20vdc) that would open contactors if value was met. I know OEM use a resistance référence, is that what you have set-up?

RetroZero wrote: ↑Thu May 12, 2022 2:43 pm I'm interested in your setup. One of the many mandatory requirements where I live. I thought of an Isa shunt between hv and châssis with a tolerance (cut-off voltage around 20vdc) that would open contactors if value was met. I know OEM use a resistance référence, is that what you have set-up?

I don't think my setup is very law abiding, unisolated charger and all that. I have no in car isolation monitor, except perhaps for the Leaf BMS. Bot not polling any isolation resistance values from it, not even sure it provides any.

A new issue is arising. I was a little alarmed by a 50mV delta between the highest and lowest cell. When I checked the cell voltages I found cell 89 reads low and cell 90 reads high, all other cells are within 10mV of each other. I'm thinking a bad cell tap contact has developed. And that is super inaccessible

johu wrote: ↑Sat May 14, 2022 5:08 pm I have no in car isolation monitor, except perhaps for the Leaf BMS. Bot not polling any isolation resistance values from it, not even sure it provides any.

When I had the BMS I sent to you, I looked up some of the chip spec sheets. One was a dedicated isolation monitor and I recall it used an oscillator circuit and any leakage current would disturb the frequency.

Since I welded the stock Nissan charge port relays yesterday I was forced to get under the car and fix that.
I decided to upgrade. Damien sent me some Gigavac relays a while back, rated 500A. So that is what I now use. Now I can finally take advantage of 100 kW chargers. BMS allows 70 kW up to 45% or so.
I use the aux contact of the one relay to switch on the second one. They safely turn on with 1.3A and 11.9V and then pull 300mA

SciroccoEV wrote: ↑Sat May 14, 2022 7:03 pm When I had the BMS I sent to you, I looked up some of the chip spec sheets. One was a dedicated isolation monitor and I recall it used an oscillator circuit and any leakage current would disturb the frequency.

Alright, will check to see if I can poll any values from it.

Early forum release

Took Touran to our summer weekend to supply it with electricity. Aaaand - no voltage coming out of Chinese inverter. Ok, returned home, removed the PCB and found the two elcaps rather swollen. Indeed, 0 uF, totally blown. Supposedly "Nichicon" - yeah right. Replaced them with a proper one aaand - still no voltage. Hmm. Wiggled the sine filter coil a bit to find both legs had broken off. Little surprise there actually, it is really heavy and only held down with cable ties.
Fixed that et voila, voltage comes out. Now off to the woods again, lets see how much energy we need.

Next modification to Touran will be an actual on board charger. I'm a bit fed up with boost mode home built chargers as I exploded it many times by now, so now I'll rather have a proper one that is built in. I charge the car at home 90% of the time and I charge slowly to make use of the 800W solar + 900W battery system. So a single phase charger will do.

So I bought that Outlander charger the marty had up for sale plus a single phase type-2 port and a granny cable. The charger is supposed to live in the exhaust tunnel and will be permanently connected to the HV battery. There is an unswitched outlet with a 30A fuse on Nissans relay box so I'll use that. That way I don't have to worry about precharge and turning on main relays.

Now, the fuel filler is already taken by CHAdeMO, so needing another spot for the type-2 inlet. Did have to remove the locking mechanism, not too worried about it.

Good job!
This now makes it OI Touran doesnt it.

i would have said that the chademo is best at the front or rear and the type two at the side but i guess this is the path of least resistance once you have already got something else installed.

@johu;
That license plate holder in English where to buy?

Did a full test run of the charger today and it works a treat! Temporarily mapped the charge current limit from the BMS to the charger modulo 128 but then noticed that ain't gonna work well if lim % 128 == 0. Might have to hard code something.
Also found message 0x38A collides with something already present in Touran but it doesn't seem to disturb. The info in that message is rather redundant and it seems the VW message always wins arbitration as it's only 4 bytes DLC.
I removed the Yakaza connector for AC inlet and mounted a Wieland connector instead.
Now I just need to find out whether it fits into the exhaust tunnel and I'm good to go.

arber333 wrote: ↑Sat Aug 27, 2022 7:28 pm Good job!
This now makes it OI Touran doesnt it.

Thanks Had the logo ready so instead of searching a good VW one I thought this would be nice.

whereswally606 wrote: ↑Sun Aug 28, 2022 11:57 am i would have said that the chademo is best at the front or rear and the type two at the side but i guess this is the path of least resistance once you have already got something else installed.

Right, it is down to the layout. DCFC doesn't go through the main relays but directly into the battery which conveniently is in the back as well.

EV_Builder wrote: ↑Sun Aug 28, 2022 4:01 pm @johu;
That license plate holder in English where to buy?

I bought these at https://kennzeichenhalterung.de/ using the SVG file that I've attached

Hm... do you want me to send you one LV connector for charger? I have one with wires pins and seal.