Generator stop timer causing problems with ac input

After shutting down my generator yesterday the MP2 would not connect to the ac input on shore power, or the generator again. Restarting vebus would again allow the mp2 to connect to incoming shore power, or generator. Connecting/disconnecting shore power would function properly every time. The problem was again replicated after running and shutting down the generator.

Venus os v3.52
Mp2 firmware 552 (2 mp2 2x120 in parallel)
Edit to add: this is in an rv. Shore power and generator are connected to an ATS, then to a surge guard, and then to ac input of the mp2ā€™s. No changes have been made to the system other than firmware updates.

The following steps were taken during diagnosis:

Remove guimods and package manager
No change

Upgrade venus to v3.54
No change

Upgrade mp2 inverters to firmware v555
No change

Restored inverter configuration to default values and uploaded fresh configuration
No change

Checked inverters in device list and saw ā€œac input ignoredā€
This idiot finally got a clue

Changed generator warmup/cooldown/stop timers to 0
Inverter ac input once again operates as expected

Set warm up time to 10 seconds
Still working properly

Set cooldown timer to 10 seconds
Still working properly

Set stop timer to 5 seconds
Incorrect behavior is back. Once again the ac input will not connect after running and shutting down the generator. Vebus reset required to connect to ac input

Set stop timer back to 0 and correct behavior of inverter is restored. Verified several times.

It appears the stop timer is not releasing the ignore ac input.

bump
@guystewart can we bring this to someoneā€™s attention @ victron?

1 Like

Hi @thomasinaz

Thanks for reporting.

If there is anyone else out there with a similar configuration that can reproduce this bug as Derrick describes, please also speak up and post here with the details.

Hi @thomasinaz

The warm-up, cool-down and generator stop time settings are only used for AC inputs configured as ā€œGeneratorā€. Please check and correct the settings of System setup ā†’ AC Input 1 and 2. If you want to use the warm-up, cool-down and generator stop time feature, set the respective input to ā€œGeneratorā€.

Please also check if the MK3 in the GX device needs to be updated as well. More info here (all the way at the bottom of the page):

https://www.victronenergy.com/blog/2023/05/31/venus-os-v3-00-generator-start-stop-improvements-ess-peak-shaving/

Can you also share the value of the ā€œStateā€ menu item of the Generator start/stop menu (assuming you use the relay to start the generator)? With all the times configured to nonzero values, it should go from ā€œRunningā€ to ā€œCool-downā€ to ā€œStoppingā€ to ā€œStoppedā€. In the transition from ā€œStoppingā€ to ā€œStoppedā€, the multi is instructed to accept the AC inputs again. Since the MP connects to the AC input after a vebus reset, Iā€™d expect the generator state to transition normally.

Thanks,
Rein.

I ran the generator again this morning with the stop time setting in order to provide the ā€˜stateā€™ output as requested. Ironically it worked as expected this time. For clarification, the ac input 1 was set to generator this time as well as previous attempts. I do recall the ā€˜stateā€™ cycling through warmup/running/cooldown/and stopped previously when the issue persisted but I wanted to run through it again to be sure since the question was asked.

For further clarification, all settings and configuration were exactly the same this time as before. The ONLY thing that is different is that the system was completely powered down yesterday in order to replace a bus bar, whereas before the cerbo had just been rebooted. Some residual garbage stuck in memory somewhere? I donā€™t know, itā€™s certainly puzzling. Computers do funny things sometimes.

Also checked the mk3 driver and it is up to date.

Hi @thomasinaz

Thanks for your answer. Please let us know (drop a message here) when the system starts misbehaving again. Iā€™d like to login remotely then to see whatā€™s going on.

Regards,
Rein.