Tesla Large Drive Unit Support Thread

[Roadstercycle]

Ok guys I got the car running but I need a little help with a setting. I've done the throttle calibration and that's no problem as it's set but I have to push the pedal down too far in my opinion to get moving. What perimeter in the settings adjusts this? I'm a bit nervous to start just going willy nilly on it. Looking forward to getting this down the road.

[Roadstercycle]

Ok guys I got the car running but I need a little help with a setting. I've done the throttle calibration and that's no problem as it's set but I have to push the pedal down too far in my opinion to get moving. What perimeter in the settings adjusts this? I'm a bit nervous to start just going willy nilly on it. Looking forward to getting this down the road.

Hi Guys, any body watching the forum anymore? Asked this question a couple days ago.

[Jack Bauer]

What voltage are you running?

[Roadstercycle]

What voltage are you running?

387 volts right now but can go 400 volts. Also I have blown two 50 ohm 100 watt pre-charge resistors, they may have been cheap Chinese ones. They blow after a couple times being used. Any idea on that?

Also can you give me an example of what numbers on the face plate you talk about when you say they can be deduced from the nameplate?
Name plate says, only PN# and Serial number and Sport. The stamping says T15J0078878 then 283,-3 28 under that. Am I missing something?

[Kevin Sharpe]

Any idea on that?

Why don't you record a video showing the issue? Also publishing the parameter file may give some clues. Everyone here is a volunteer with limited time so the more information you provide the more likely you are to get help.

[tom91]

Specially since your description can have many causes.

Make a trace of Potnom vs Pot1 and see if it makes sense. Does it really take alot of Pot 1 to achieve positive potnom?

If yes off throttle regen is causing the deadspot in the beginning.

If no and it takes alot of Potnom to make the motor spin, check other none throttle related settings.

[johu]

Ok guys I got the car running but I need a little help with a setting. I've done the throttle calibration and that's no problem as it's set but I have to push the pedal down too far in my opinion to get moving. What perimeter in the settings adjusts this? I'm a bit nervous to start just going willy nilly on it. Looking forward to getting this down the road.

Hi Guys, any body watching the forum anymore? Asked this question a couple days ago.

Well one day isn't a couple of days
You can get the throttle to react earlier by reducing "brknom". Maximum breaking force will stay unchanged but pedal travel can be adjusted.
Pre-charge: I found initial pulses kill resistors. 50 Ohm means the inrush current is 8A and cheap resistors don't take that very often. Either increase resistance to about 1k (not much capacity in modern inverters anyway) or use a high watt (>50W) wirewound resistor if you insist on fast precharging.

[tom91]

At Zero-EV we use TWO 100 watt 30 ohm resistors in series for precharging on large system (Large drive unit and then multiple HV components). Reduces the power per resistor and ours have yet to fail.

[johu]

Are you running any loads via the resistors before the main contactor closes? Like the DC/DC converter? Then yes, you need strong resistors.
In Polo I'm only running the inverter on the HV bus (820µF) and have been using a 1k, 10W wire-wound resistor for 5 years now.

[Roadstercycle]

Any idea on that?

Why don't you record a video showing the issue? Also publishing the parameter file may give some clues. Everyone here is a volunteer with limited time so the more information you provide the more likely you are to get help.

Thank you Kevin, Here's the file

params.json

(1.29 KiB) Downloaded 426 times

[Roadstercycle]

Ok guys I got the car running but I need a little help with a setting. I've done the throttle calibration and that's no problem as it's set but I have to push the pedal down too far in my opinion to get moving. What perimeter in the settings adjusts this? I'm a bit nervous to start just going willy nilly on it. Looking forward to getting this down the road.

Hi Guys, any body watching the forum anymore? Asked this question a couple days ago.

Well one day isn't a couple of days
You can get the throttle to react earlier by reducing "brknom". Maximum breaking force will stay unchanged but pedal travel can be adjusted.
Pre-charge: I found initial pulses kill resistors. 50 Ohm means the inrush current is 8A and cheap resistors don't take that very often. Either increase resistance to about 1k (not much capacity in modern inverters anyway) or use a high watt (>50W) wirewound resistor if you insist on fast precharging.

Sorry Johu, Seemed like 2 days in the states. I left the question at 2:30 AM Ireland time and it was the afternoon here, my bad. Thanks for the insight into brknom and resisters.

[Kevin Sharpe]

Thank you Kevin, Here's the file

Great... unfortunately I don't understand this stuff but lots people here do

I'd strongly recommend posting more details of your wiring/system because you should not be destroying precharge resistors and the Tesla inverter is easy to destroy.

[Roadstercycle]

Thank you Kevin, Here's the file

Great... unfortunately I don't understand this stuff but lots people here do

I'd strongly recommend posting more details of your wiring/system because you should not be destroying precharge resistors and the Tesla inverter is easy to destroy.

Hi Kevin, My wiring is exactly like the diagrams that are from Damien on this website. I just copied them. I did find out that the resistors where actually Chinese mis-labeled junk. I bought a new one from Ohmlite and it is about 4 times as big as the Chinese one. I believe that should fix that issue, I will find out today.

[Roadstercycle]

Specially since your description can have many causes.

Make a trace of Potnom vs Pot1 and see if it makes sense. Does it really take alot of Pot 1 to achieve positive potnom?

If yes off throttle regen is causing the deadspot in the beginning.

If no and it takes alot of Potnom to make the motor spin, check other none throttle related settings.

Can you only get a trace while driving the car? Can it be on a lift? How do you trace just Potnom and Pot 1? I could not find an example here how to do it. Sorry to be a noob I just don't want to make a mistake.

[johu]

You can trace pot and potnom while stationary. Also read this https://openinverter.org/wiki/Web_Interface

[Roadstercycle]

Thank you johu

[Roadstercycle]

You can trace pot and potnom while stationary. Also read this https://openinverter.org/wiki/Web_Interface

I did the trace of pot 1 and potnom.
Pot1 went up and down where as potnom never moved, straight line. I may be doing it wrong. I had HV disconnected and only running 12 volt battery power to the inverter. Should I be doing it different? The car does move back and forth in the driveway so I am pretty sure I'm doing the trace wrong because the car moves and if potnom doesn't move the car should not move, Correct?

[Roadstercycle]

You can trace pot and potnom while stationary. Also read this https://openinverter.org/wiki/Web_Interface

I was able to get the correct traces now, I put the car on the hoist and actually ran it. Pot1 and Potnom seem to go up together pretty nicely but as you said it seems to take a lot of Pot1 to get the motor spinning. Unfortunately without any type of tutorial as to what everything does it's a bit worrisome to just start tweaking things. At the moment I have the exact same settings as Damien on his large motor but I am running the Sport motor so there could be a couple settings that need to be bumped. I'll keep reading and try to figure which ones may need the tweak. It may be the fweak but at this point I do not know how to decipher the motor name plate numbers that Damien talks about in the Motor parameters on the openinverter.org page, that's all it may need. I'm still reading and learning. I am going to try upping the boost a bit at a time.

[johu]

I wouldn't play with the motor parameters just yet, rather the throttle and regen ones.
The wiki is open to everyone (same login as forum) so feel free to write up your findings there. This is open source for a reason: you are now officially a prosumer

[jon volk]

You can trace pot and potnom while stationary. Also read this https://openinverter.org/wiki/Web_Interface

I was able to get the correct traces now, I put the car on the hoist and actually ran it. Pot1 and Potnom seem to go up together pretty nicely but as you said it seems to take a lot of Pot1 to get the motor spinning. Unfortunately without any type of tutorial as to what everything does it's a bit worrisome to just start tweaking things. At the moment I have the exact same settings as Damien on his large motor but I am running the Sport motor so there could be a couple settings that need to be bumped. I'll keep reading and try to figure which ones may need the tweak. It may be the fweak but at this point I do not know how to decipher the motor name plate numbers that Damien talks about in the Motor parameters on the openinverter.org page, that's all it may need. I'm still reading and learning. I am going to try upping the boost a bit at a time.

Change your slipstart value to 35 and report back.

[Roadstercycle]

You can trace pot and potnom while stationary. Also read this https://openinverter.org/wiki/Web_Interface

I was able to get the correct traces now, I put the car on the hoist and actually ran it. Pot1 and Potnom seem to go up together pretty nicely but as you said it seems to take a lot of Pot1 to get the motor spinning. Unfortunately without any type of tutorial as to what everything does it's a bit worrisome to just start tweaking things. At the moment I have the exact same settings as Damien on his large motor but I am running the Sport motor so there could be a couple settings that need to be bumped. I'll keep reading and try to figure which ones may need the tweak. It may be the fweak but at this point I do not know how to decipher the motor name plate numbers that Damien talks about in the Motor parameters on the openinverter.org page, that's all it may need. I'm still reading and learning. I am going to try upping the boost a bit at a time.

Change your slipstart value to 35 and report back.

John, I am reporting back. No noticeable change in throttle. My base throttle is 935, I get no motor movement until 1650 on the trace. About the same as slipstart 50.

[tom91]

John, I am reporting back. No noticeable change in throttle. My base throttle is 935, I get no motor movement until 1650 on the trace. About the same as slipstart 50.

Set the brknom to 0. At what point the motor start spinning then?

[Roadstercycle]

John, I am reporting back. No noticeable change in throttle. My base throttle is 935, I get no motor movement until 1650 on the trace. About the same as slipstart 50.

Set the brknom to 0. At what point the motor start spinning then?

Set the brknom to 0 and the motor starts almost immediately, backed off to 10.
Thank you Tom. One part of the mystery solved unless doing that reflects on other settings.

[tom91]

Set the brknom to 0 and the motor starts almost immediately, backed off to 10.
Thank you Tom. One part of the mystery solved unless doing that reflects on other settings.

Why one part? You wanted the motor to spin sooner so now it does. The section of the throttle that does regen is determined by brknom, nothing else changes not even the regen level.

Any other behaviour that you feel is unexpected.

[Roadstercycle]

Set the brknom to 0 and the motor starts almost immediately, backed off to 10.
Thank you Tom. One part of the mystery solved unless doing that reflects on other settings.

Why one part? You wanted the motor to spin sooner so now it does. The section of the throttle that does regen is determined by brknom, nothing else changes not even the regen level.

Any other behaviour that you feel is unexpected.

Thank you Tom, As a noob to all this I was not sure what else may have been affected. I wish I was well versed in the controller aspects so I could do a you tube video to clear up any confusion on all the parameter settings. In the description brknom means Regen pedal travel. Which tells me when you let off the pedal there's a part of the pedal pot where the regen starts. I had no idea it also is when you push the pedal that area of the pedal travel is dead when pushing it. Hopefully this helps someone else in the future, again thank you for helping me out.

Jack