Direction Switch Opens Contactor [SOLVED]

[ekohn04]

Hey everyone, I'm trying to spin my LDU with an open inverter board at the moment. I have been able to complete precharge, send a start signal and close the main contactor, and I read 24.6V at the inverter (using two car batteries to bench test). However when I send pin7 12 volts in order to put the LDU into drive, I hear my main contactor open and my voltage at the inverter drops rapidly to zero. The same thing happens when I try to put it in reverse. Has anyone had this issue before? I haven't been able to find it replicated on the forum. Thanks!

[ekohn04]

UPDATE: Disconnected pedal (e46) and encoder pins, direction selection no longer opens contactor. On the web interface I can see my selected direction (fwd) and my voltage (26.34). When I turn on ignition and then press "start motor in manual mode" on the interface my contactors open and I lose voltage at the inverter. When I turn on ignition and give a start signal (closing main contactor), then apply 12v to pin7(fwd), then enter values for "fslipspnt" and "ampnom," any values cause the main contactor to open and for my voltage to start dropping to zero. From these examples it seems to me like any input to spin causes my inverter to shut off.

[johu]

Sounds like a blown inverter which is detected as soon as pwm starts

[catphish]

The fact that your contactor is opening suggests you have your inverter configured to open contactors when a fault occurs. This is a very bad idea and can cause damage to the inverter. In your case though I suspect this is a symptom of the problem and not the cause, but I strongly suggest changing this setting.

Next, check if the fault is OVER CURRENT.

Is it is then for probably have a broken LDU (a blown IGBT). This is unfortunately very common on salvage units.

[P.S.Mangelsdorf]

The fact that your contactor is opening suggests you have your inverter configured to open contactors when a fault occurs. This is a very bad idea and can cause damage to the inverter. In your case though I suspect this is a symptom of the problem and not the cause, but I strongly suggest changing this setting.

Specifically, the setting is called tripmode and should be set to 1 (keep DC switch closed)

Is it is then for probably have a broken LDU (a blown IGBT). This is unfortunately very common on salvage units.

When you had the inverter open to swap out the control board, did you notice any bubbling in the gel? That seems to be a fairly decent indicator of a damaged unit.

[muehlpower]

I hope you have a separate 12V supply for the logic board and not the 12V tapped from one of the two batteries!

[ekohn04]

Thank all of you for your comments and assistance.

probably have a broken LDU (a blown IGBT).

Thank you for your expertise. I am holding out hope that this is not the case but it seems like it might be.

Specifically, the setting is called tripmode and should be set to 1 (keep DC switch closed)

I would have not known where to look for this setting, so thank you. I changed tripmode from "AllOff" to "DcSwOn," my other options are "Precharge On" and "AutoResume." With this setting I am still not able to manually start the inverter without the main contactor opening. However when I start the inverter with a 12v signal to pin23, then enter values into "fslipspnt" and "ampnom," I hear a high pitched whining (which I know is indicative of the motor spinning), and as I increase the values I hear a single knocking sound for each increase of value. I am able to see the splines in my drive unit spin in correlation with this knocking sound, but only briefly. It's as though my inverter is only sending out a blip of current, allowing my motor to begin spinning momentarily, maybe an 1/8th turn.

Next, check if the fault is OVER CURRENT.

When my contractors shut off after attempting manual start mode I cntrlF'd for "OVERCURRENT" but my find function did not locate any results. I am under the command tab. Please let me know if I am looking in the wrong place for this error code.

I hope you have a separate 12V supply for the logic board

I do have a separate 12v battery in order to send 12v signals to my logic board. 3 batteries in total.

[ekohn04]

Here is a plot of what I am describing.

[ekohn04]

UPDATE: I hooked up the pedal(e46) and plugged in the encoder wires. As soon as I give my direction signal, with no input from the pedal applied, the motor starts spinning. However, it spins very slowly with a rhythmic knocking sound. Depressing the pedal does nothing. The posts on my two 12v batteries start smoking, and I can see one of my cables supplying 25v into my HV box jump. Here is an amp plot.

[P.S.Mangelsdorf]

Error codes are shown in the spot values section, below the parameters.

The jerky/rhythmic motion sounds like a reversed encoder (a common LDU problem, it seems Tesla swapped the pinout at some point), but could also be a setting issue.

The start up without any pedal input sounds like it has idle enabled. Can you download and share your parameter file?

(also, in case you haven't yet, peruse the parameter descriptions here: https://openinverter.org/wiki/Parameters )

[muehlpower]

That sounds like a wrong wired encoder. Have you tried swapping the A and B signals?

[ekohn04]

Error codes are shown in the spot values section, below the parameters.

I was able to produce an OVERCURRENT error by flipping the sign on "ocurlim" so I'm confident that OVERCURRENT is not the issue. However I flipped A and B on the encoder side and it had no effect on my issue. I may be missing an encoder signal as from what I understand that can present itself similarly to swapped encoder wires but I don't have the correct tools to test for that, nor do I understand how to remedy that issue.

Can you download and share your parameter file?

I will absolutely do this once I am able to set up my motor again today. I will upload my parameters as well as compare mine with other people's functioning parameters.

Either way, encoder issues don't explain why my inverter opens my main contactor when I start in manual mode, even with the setting "DcSwOn" set.

Thank you both again for your continued help.

[P.S.Mangelsdorf]

Either way, encoder issues don't explain why my inverter opens my main contactor when I start in manual mode, even with the setting "DcSwOn" set.

That is an odd issue. Can you confirm how you have your contactors wired (photo and/or diagram)?

[ekohn04]

Can you download and share your parameter file?

Here is the parameter file.

params.json

(1.29 KiB) Downloaded 47 times

contactors wired (photo and/or diagram)?

The wiring diagram I used is also attached. It's from Damien's GitHub. I realized the issue when starting in manual mode is not one of my contactors opening, it's the main contactor failing to close. The clicking I mistook for a contactor opening was my precharge relay opening. This is probably due to either me not performing a manual precharge, or from udcsw being 12. I'm scared to lower this value to 0 due to user catphish's warnings throughout the forum.

[P.S.Mangelsdorf]

From those parameters and based on your description above, things should be working properly. If the inverter is seeing 24V, you should not need to lower udcsw below 12V.

We're reaching the limit of my experience, because out of either hubris or stupidity, I never bench tested my setup, I went straight for pack voltage.

HOWEVER, I did have some contactor and precharge struggles, so here are a few things to check:

• Really go through your wiring again and make sure that everything matches the diagram. Note: This may be obvious or sound stupid, but it was something I screwed up the first time by misreading the diagram: the LDU does not supply the 12V positive to either HV contactor. The LDU controls the 12V ground side; your ignition key provides the 12V+ to each contactor and to pin 1 of the LDU

• test your contactors (disconnected from the drive unit) and make sure you can hear each one cycle when you apply 12V. I had a contactor fail shortly after install for no good reason. I had bought 3 identical ones, and one was bad.

• make sure that all of your 12V grounds are connected. Tesla parts seem to be overly sensitive to grounding. I don't know of this being an LDU issue, but its worth checking.

[ekohn04]

Thank all of you for your help! After using a parameter set from the parameters link in the wiki, changing some pot values, and rewiring my pedal correctly, I was able to get a response from my pedal. I'm still only getting a very slow jerking motion accompanied by knocking sounds from the motor regardless of my encoder A&B config, but I believe it's due to a dirty encoder signal. I'm going to make a separate post in order to make sure I'm going in the right direction with my thinking.

HOWEVER, I did have some contactor and precharge struggles, so here are a few things to check:

I'm all wired up correctly and everything else is working fine so I think I'm gonna throw the manual start issue near the bottom of the importance list for now.

I'm very thankful for the community as you guys have been nothing but amazingly helpful and kind, and a fantastic free resource. I'm only 18 so I've got a to learn from everyone here but I hope in a couple years I'll be the one passing down the knowledge. Thanks again.