openinverter forum

I am using an SDU with I am looking to do 2 related things:

1) I would like my charger to inhibit the inverter using CAN when an EVSE is connected, to prevent driving if a cable is attached. Is there any simple way to fully inhibit inverter output (such as forcing neutral gear) via CAN? Or is there a particular parameter I should set that would achieve the same effect?

2) I would like a physical inverter shutdown button (the opposite to the start button). Does the firmware have any provision for such a button?

catphish wrote: ↑Sat Jun 18, 2022 12:00 pm I am using an SDU with I am looking to do 2 related things:

1) I would like my charger to inhibit the inverter using CAN when an EVSE is connected, to prevent driving if a cable is attached. Is there any simple way to fully inhibit inverter output (such as forcing neutral gear) via CAN? Or is there a particular parameter I should set that would achieve the same effect?

2) I would like a physical inverter shutdown button (the opposite to the start button). Does the firmware have any provision for such a button?

There should be a BMS pin which when active can inhibit regen or torque or both. You set it in parameters under "Derating". See "bmslimhigh" and "bmslimlow". That should be used together with BMS signal for OV or UV however.
Also with Openinverter gen3 there is MPROT pin which is pulled high. When low it inhibits PWM. I think that would be equivalent to complete torque removal.
You could open both "FWD" and "REV" signals at the same time as this would indicate an error....
You do need to set DC contactor to be allways on in that case.

Hm... in your CAN case, you could simply command preprogrammed CAN bits. See here:
https://openinverter.org/wiki/CAN_commu ... IO_via_CAN

Moved to inverter firmware

arber333 wrote: ↑Sat Jun 18, 2022 3:05 pm There should be a BMS pin which when active can inhibit regen or torque or both. You set it in parameters under "Derating". See "bmslimhigh" and "bmslimlow". That should be used together with BMS signal for OV or UV however.
Also with Openinverter gen3 there is MPROT pin which is pulled high. When low it inhibits PWM. I think that would be equivalent to complete torque removal.
You could open both "FWD" and "REV" signals at the same time as this would indicate an error....
You do need to set DC contactor to be allways on in that case.

Hm... in your CAN case, you could simply command preprogrammed CAN bits. See here:
https://openinverter.org/wiki/CAN_commu ... IO_via_CAN

Unfortunately, the SDU board has no external MPROT pin. It would be ideal for the stop button if it was present.

I intend to use the BMS (via CAN) pin for actual derating when the battery is low, so that's also off the table.

Activating both FWD and REV simultaneously sounds like it could work for both use cases, so I'll look more closely at that, thanks!

Did you come up with a solution?

I'm getting ready to wire up my Brusa charger. I really would like to wake on can when the proximity signal is detected from J1772, but since I am using the openinverter board in the SDU for contactor control I need to trigger start (via Can) but then need to inhibit drive.

I use canio for this. Sends start but in neutral. https://openinverter.org/wiki/CAN_communication

The way I solved this in the end was to use CAN for my start signal and route it via the charge controller. This way the start button won't do anything if the vehicle is charging because the charge controller won't forward the start signal. I decided this was the safest approach as it inhibits start, but means no external components are unnecessarily involved during driving. canio is nice and flexible, and allows pretty much any combination of this.

I never built an emergency shutdown button, as I decided it would be sufficient just to drop the car into neutral if needed. The software is sufficiently robust at shutting down the inverter when no gear is selected.

Just one question: what if the inverter is already started and then you plug in?