Tesla Large Drive Unit Support Thread

[Mowza]

Hey everyone, new guy here but no noob to electricity or cars.

I have a P85D setup I am performing low voltage testing to. I based my bench test off of Roadstercycle's youtube video and the diagrams posted on this thread. This thread was very much instrumental in getting as far as I have!

I have a 12v marine battery fully charged. Running a 5A fuse for the 12v inputs. I have a 30A breaker between the main contactor and motor +. UDCSW is 2 (10v less than testing voltage) and UDCMIN is 0. Everything works perfectly except when I got to give it some throttle (E46 pedal). I get a very slow and very slight rotation of the motor before my 30A breaker trips. It did the same thing with UDCSW at 0. I looked through this thread for any insight but I must admit I could not find the answer. I also tried clicking on "start inverter in manual mode" since I am not using an encoder at this time. It had no effect.

Any help would be much appreciated. Thank you for your time!

[jon volk]

You’re trying to spin the motor on 12v? Thats about 90v shy of where you should be for testing.

[Mowza]

While that certainly makes sense the reason I chose 12v was because that is exactly what was used in this video:



and it seems to work just fine for an initial low speed test. I do not see any other power source in it and everything seems to be wired to the battery on the table.

[muehlpower]

at 4:25 he says that he has it running with 50-70V!

I run mine with 48V (4x 12v starter batterie)

[Mowza]

I guess I was too focused on his wiring at the time trying to figure out the small relays he had on his test board. I will have to get a few more batteries then! Thanks for pointing that out. I could have watched the video again and I still would have most likely missed that lol.

[EvSteeve]

Good Morning guys,
Hoping you can help me out here.

Im very new to Tesla motors and Evs in general, Ive got my first Tesla LDU and have set it up on the bench in an attempt to test it.

Im getting a very slow 'Jogging' motion when applying throttle - Much like alot of people have described when signal wires need to be inverted from the encoder - However i have tried this with no joy.
(shielding is connected to pin 18 etc so interference shouldn't be an issue either)
Is there a way of testing the encoder without and oscilloscope? - I've Tried, connecting the 5v feed and ground to the encoder and spinning the motor by hand to see if i get a fluctuation of voltage from the signal pins, however it stays at 4.5 V consistently - Could my encoder be faulty or is this not a sufficient way of testing?

Regards and thanks in advance.

[Mowza]

Got all my problems solved and had a successful test. The panzer parameters saved the day! Now on to the next step, testing at 120 volts using some of my S3 modules. Thank you to the few who chimed in to point me in the right direction.

[jon volk]

Good Morning guys,
Hoping you can help me out here.

Im very new to Tesla motors and Evs in general, Ive got my first Tesla LDU and have set it up on the bench in an attempt to test it.

Im getting a very slow 'Jogging' motion when applying throttle - Much like alot of people have described when signal wires need to be inverted from the encoder - However i have tried this with no joy.
(shielding is connected to pin 18 etc so interference shouldn't be an issue either)
Is there a way of testing the encoder without and oscilloscope? - I've Tried, connecting the 5v feed and ground to the encoder and spinning the motor by hand to see if i get a fluctuation of voltage from the signal pins, however it stays at 4.5 V consistently - Could my encoder be faulty or is this not a sufficient way of testing?

Regards and thanks in advance.

Post your software parameters

[EvSteeve]

Hi John,
Thanks for the response.

Here are my parameters!

Thanks again.

Ps - cannot get inverter to run in manual mode? Will only 'Run'

[EvSteeve]

Hi there,

Any ideas having looked at my parameters?

Really stuck any help massively appreciated!!

Regards

[P.S.Mangelsdorf]

Hi there,

Any ideas having looked at my parameters?

Really stuck any help massively appreciated!!

Regards

Did you start with a known parameter example such as Jon's? If not, start by comparing your parameters to a known set, and see if any are significantly different.

[Clanarn]

A follow up on my problem with the overcurrent and blowing fuse. I tested the igbts like you explained johu. All 6 read 0.350v-0.365v. I will be inspecting the board now. Any Ideas how to proceed?:)
Thx

Edit. Board visually good. Can’t find anything loose

[jon volk]

What voltage are you powering it with currently?

[Clanarn]

70v. 50Ah lithium so plenty of power. Had 350v when the problem started. Still blowing fuses now with 70v tho.

[jon volk]

Sorry, I was referring to EvSteeve

[EvSteeve]

48v (4x 12v batterys in series)

Thanks for the response!

Regards

[Boxster EV]

48v (4x 12v batterys in series)

Thanks for the response!

Regards

Sounds simple but have you calibrated the throttle pedal? Potmin looks quite high.

[jon volk]

48v (4x 12v batterys in series)

Thanks for the response!

Regards

Try setting udcnom to 0.

Also, same about potmin mentioned above.

[EvSteeve]

Yes, calibrated throttle. Did think when calibrating that potmin value seemed a bit high compared to other parameters I've seen.

Is it worth trying another throttle? I have a Prius here, but currently have it on a zero ev hall effect throttle.

Thanks for the help guys

[Boxster EV]

Yes, calibrated throttle. Did think when calibrating that potmin value seemed a bit high compared to other parameters I've seen.

Is it worth trying another throttle? I have a Prius here, but currently have it on a zero ev hall effect throttle.

Thanks for the help guys

No need to change throttle if it’s calibrated correctly.

Everything you describe points back to encoder wiring. Have you triple checked all of the pins are seated (checked for continuity at each end of the plug), and for sanity, tried swapping the signal wires (again)?

[EvSteeve]

Okay, will try recalibrating just to be sure.

Yes have checked encoder connections and feel pretty confident in them as have checked continuity.

Will double triple check later though as can never be to sure, and will also try swapping signal wires over again.

I agree it all points to an encoder fault, however when I try to run in open loom - (just to see it spin!) I cannot get my inverter into manual! Anyone had this issue before?

Thanks again everyone for the help! Really appreciate it!

[Mowza]

What is the recommended wire gauge to use for a 120v bench test run using 5 S3 battery modules? Is 10 gauge wire sufficient? I am assuming the amperage draw will still be low, below 30A.

Also is it imperative that one use insulated tools assembling a battery array at voltages over 50VDC?

[celeron55]

What is the recommended wire gauge to use for a 120v bench test run using 5 S3 battery modules? Is 10 gauge wire sufficient? I am assuming the amperage draw will still be low, below 30A.

Also is it imperative that one use insulated tools assembling a battery array at voltages over 50VDC?

Always use a fuse according to your wiring. Then almost any wiring is safe. Take into account the DC voltage rating of the fuse - 12/24V fuses and glass tube fuses may result in an electric arc or basically a small explosion.

Insulated tools are always wise when assembling any batteries. You can DIY fairly effective ones by using good quality heat shrink tubing or even a couple of layers of electrical tape if the tools are used lightly.

[Mowza]

I am currently using a 30A automotive breaker that I am assuming is rated for 12/24v. It held up perfectly with the 50v setup but I'm not sure how it will like 120v even at the low amperage of the unloaded motor. I ordered a small set of insulated tools that should be all I need for connecting the battery wiring. What type of circuit protection did you use for the higher voltage bench testing? I'm not finding DC fuses rated for the 120 volt range at around 30A.

[muehlpower]

I am currently using a 30A automotive breaker that I am assuming is rated for 12/24v. It held up perfectly with the 50v setup but I'm not sure how it will like 120v even at the low amperage of the unloaded motor. I ordered a small set of insulated tools that should be all I need for connecting the battery wiring. What type of circuit protection did you use for the higher voltage bench testing? I'm not finding DC fuses rated for the 120 volt range at around 30A.

https://www.digikey.de/product-detail/d ... ND/5233890