Tesla SDU forward direction

[johu]

Today I received the second report that the SDU spins in reverse when forward direction is selected. One user might have even damaged the gearbox because he spun up too fast in reverse.
Due to due a lack of an SDU I can't test this myself, but I'm assuming this will be the same for all SDUs and people are just used to make do. So be careful when spinning up.

[Isaac96]

I will test once I get my coolant lines installed. 4.97 firmware on my board.

[muehlpower]

My LDU also runs backwards when I give a forward signal. I just swapped the cables and didn't think about it any further!

[Peter]

As I am about to install my SDU which will be running in reverse based on the normal Tesla layout should I be concerned ?? I have removed the mechanical oil pump and added an external electric oil pump so thats not the issue.

[johu]

No reason for concern then. With installed in reverse you even get correct display

[Peter]

Thanks Johannes. I can dry my tears now

[Isaac96]

Just tested my SRDU, can confirm it's backwards. Wonder how that came about...
I presume I can just switch my F/R wires and nothing will behave differently?

[johu]

Yes, no different logic in reverse. You can also set dirmode to "SwitchReversed" if you don't want to pull wires.

[EV_Builder]

Yes, no different logic in reverse. You can also set dirmode to "SwitchReversed" if you don't want to pull wires.

I advice people to switch internally the motor phases (in the software configuration), not the wiring of the inputs or the software logic etc.
Forward needs to be forward en reverse needs tobe reverse...

If you swap stuff there might be a risk in the future with updates which are made to work in forward mode etc. etc..
For example a reverse throttle tuning with speed limiter for more feeling during parking etc.
Or a ramp/hold mode which activates in forward gear only...

[johu]

Yes, fair point.

[SciroccoEV]

I did at one stage suggest an option to reverse the motor direction for Forward signal.

[Johannes.l]

I can also confirm that my SDU spins in reverse when it should go forward.
So it's enough to set it to "SwitchReversed" then? One less problem to think about at least.
/Johannes

[EV_Builder]

I can also confirm that my SDU spins in reverse when it should go forward.
So it's enough to set it to "SwitchReversed" then? One less problem to think about at least.
/Johannes

Not too familiar with the software yet because still building the car.
The motor ran, so I left that for later.

If the forward input makes you go forward with that setting or another you should be covered.

[Peter]

Its good to know you can achieve max speed in forward or reverse, James Bond would approve

[johu]

At least nobody complained so far

[catphish]

I realise this is already well established, but I just want to add a "+1" here. Like others else, my SDU runs in reverse when configured for forward direction. Would love to see a setting to reverse the hardware direction, rather than having to reverse the input direction selector if someone has time to add such a feature. I'm not sufficiently familiar with the code to do it myself yet.

[qmedia2651]

That's weird my SDU unit runs forward like it should
Using v5 logic board done by jclpcb and populated my self.
JOHU HELP WITH THE PARAMETERS

[catphish]

It turns out this wasn't a problem for me because I actually *wanted* to run my SRDU in reverse. Perhaps this is true of the majority of people using these drive units

[ViktorT]

I just testspinned my SDU this weekend and I have two questions. Exactly how should I apply the command switchReversed in the user interface?
Also there is a kind of cogging sound when the motor spins, is that common and no problem or something that needs a fix? There is no oil in it yet

[catphish]

I just testspinned my SDU this weekend and I have two questions. Exactly how should I apply the command switchReversed in the user interface?

switchReversed should be an option under the "dirmode" setting dropdown.

Also there is a kind of cogging sound when the motor spins, is that common and no problem or something that needs a fix? There is no oil in it yet

I had the same thing while running my SDU on the bench at lower voltage with no oil, so it's probably not something to worry about. However, it's generally not a good idea to run it too much with no oil anyway, as it can reach high speeds very easily with no load.

[ViktorT]

Thanks Catphish

[caymanS]

I also experienced SDU spinning backward when I selected forward (small rear drive unit).

[mane2]

Oh! This explains why hill-hold did not work on my LDU!

Next question: How to "switch internally the motor phases (in the software configuration)" the right way?

[mane2]

I didn't see any option in web interface where to switch motor phases.

Only parameter related to phases is

Code: Select all

syncofs	dig	0	65535	0	Phase shift of sine wave after receiving index pulse

Has anyone done this actually? Maybe it was just wishful thinking?

[johu]

There is no option to swap phases in sine firmware. Only option to swap forward/reverse pins