Low power mode discharge

[uxbpncgw]

Hi,

I am currently a week or two into using predbat to manage my foxess setup via cloud (not modbus). I'm looking at the export slots at the end of the day and trying to reduce the long term wear on the battery. In our house we use negligible amounts of power between 10pm and midnight. The low power mode seems quite inconsistent and frequently does 20 mins at 5kw then 1 hour of 7kw (inverter max). Is there a way to spread out the discharge between 10pm and midnight every day?

Settings at present:
Combine export slots is ON
Low power export mode is ON

Also, I had an episode where my battery drained to 8% (Fox says lowest SOC is 10%) a few days ago. Could have just been bottom balancing but I'm keen to avoid predbat trying to get into that zone. I have set my minimum set reserve min to 11% - is that adequate or do I need to go into expert mode and specify a remaining kWh?

Thanks for all help/advice.

[gcoan]

The low power mode seems quite inconsistent and frequently does 20 mins at 5kw then 1 hour of 7kw (inverter max). Is there a way to spread out the discharge between 10pm and midnight every day?

low power mode should be entirely automatic so if you are not seeing that then it suggests an issue with predbat controlling the inverter charge rate. Best you log a separate issue on that and include the logfiles, debug.yaml and graphs of the inverter charge rate

[gcoan]

I have set my minimum set reserve min to 11% - is that adequate or do I need to go into expert mode and specify a remaining kWh?

Setting reserve min should be sufficient. Predbat will use this when planning and instructing the inverter to discharge - the discharge instruction will set this reserve value.

Even with this, it's possible that the inverter won't 100% honour this limit. My inverter reserve is 4% but I've seen it sometimes reporting that it is at 1%. Predbat doesn't command that, it's just that the inverter believes that this is what the current SoC is. Remember that SoC % is an approximation, the inverter can't measure it, all it can measure is voltage of the battery cells, and from that it derives the SOC %

[uxbpncgw]

Ok thanks.

So just to confirm that with those settings you wouldn't expect this to be the plan (attached).

[gcoan]

So just to confirm that with those settings you wouldn't expect this to be the plan (attached).

I'm not sure I follow what the question is.

What I see in the plan is the battery being exported down to a limit of 11% before midnight, and at midnight the SoC is 11%, and the battery starts charging, with the plan to be at 100% by the end of the cheap period.

This all looks fine.

There is possibly the opportunity for predbat to do a partial discharge and recharge overnight in the cheap period depending on your inverter rate and battery capacity, and whether you have slow rate charge turned on and combine charge slots off. But as a basic plan it looks fine to me

[uxbpncgw]

Sorry, my wording was incorrect on the last reply which confuses things further. My main aim is to spread the discharge later on in the day over a longer time window so that the discharge rate is 3kw (ish) instead of the inverter maximum as it currently plans (7kw). With the settings I have switched on (low power mode and combine slots) is this plan the expected output or should I post the logs etc? If this is expected behaviour is there another workaround to achieve this? Thanks Alex

…

On Tue, 8 Sept 2026, 22:52 Geoffrey Coan, ***@***.***> wrote: So just to confirm that with those settings you wouldn't expect this to be the plan (attached). I'm not sure I follow what the question is. What I see in the plan is the battery being exported down to a limit of 11% before midnight, and at midnight the SoC is 11%, and the battery starts charging, with the plan to be at 100% by the end of the cheap period. This all looks fine. There is possibly the opportunity for predbat to do a partial discharge and recharge overnight in the cheap period depending on your inverter rate and battery capacity, and whether you have slow rate charge turned on and combine charge slots off. But as a basic plan it looks fine to me — Reply to this email directly, view it on GitHub <#4988?email_source=notifications&email_token=CNXRYQ23HTMKY4LZ7QS7S6T5OB5S3A5CNFSNUABIM5UWIORPF5TWS5BNNB2WEL2ENFZWG5LTONUW63SDN5WW2ZLOOQXTCOBTGU3TGOJRUZZGKYLTN5XKMYLVORUG64VFMV3GK3TUVRTG633UMVZF6Y3MNFRWW#discussioncomment-18357391>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/CNXRYQ7DRE3HW7WW5DD2EUD5OB5S3AVCNFSNUABIKJSXA33TNF2G64TZHM3DGNBUHA2TCMZWHNCGS43DOVZXG2LPNY5TCMBXGY4DMMJZUF3AE> . Triage notifications, keep track of coding agent tasks and review pull requests on the go with GitHub Mobile for iOS <https://github.com/notifications/mobile/ios/CNXRYQ57QF3AXGGDLONLHVT5OB5S3A5CNFSNUABIM5UWIORPF5TWS5BNNB2WEL2ENFZWG5LTONUW63SDN5WW2ZLOOQXTCOBTGU3TGOJRUZZGKYLTN5XKMYLVORUG64VFMV3GK3TUVJTG633UMVZF62LPOM> and Android <https://github.com/notifications/mobile/android/CNXRYQ462ZDUCI23G76LMT35OB5S3A5CNFSNUABIM5UWIORPF5TWS5BNNB2WEL2ENFZWG5LTONUW63SDN5WW2ZLOOQXTCOBTGU3TGOJRUZZGKYLTN5XKMYLVORUG64VFMV3GK3TUVZTG633UMVZF6YLOMRZG62LE>. Download it today! You are receiving this because you authored the thread.Message ID: ***@***.*** com>

[planetming]

Doesn't this Config do low power discharging? switch.predbat_set_export_low_power
I've set True and I sometimes get lower discharge power in slots, with the snail emoji.
The documentation doesn't cover it, but the option is there.

[planetming]

I have a self imposed export limit of 4000W. But I slow down the export by setting the Apps value inverter_limit_export: 400 to 400W in my case. I use this low value specifically for the saving session slots just so I qualify for the free weekend hour.

[gcoan]

Doesn't this Config do low power discharging? switch.predbat_set_export_low_power

I've set True and I sometimes get lower discharge power in slots, with the snail emoji.

The documentation doesn't cover it, but the option is there.

If it's not in the documentation, then that's why I couldn't find it! I'll get it added

Yes this should do what you want

[uxbpncgw]

Thanks. Yes I have the export low power mode enabled but it only ever seems to do 15 mins at a lower rate then back to full inverter discharge rate. I just want to increase the snail rate by more than 15-30 mins to say 1-2 hours to reduce the wear on the battery

[planetming]

I have a self imposed export limit of 4000W. But I slow down the export by setting the Apps value inverter_limit_export: 400 to 400W in my case. I use this low value specifically for the saving session slots just so I qualify for the free weekend hour.

The new addition to the manual API feature in v9.6.3 is exactly what I needed to control lower exports during Saving Sessions. "inverter_limit_export can now be overridden, like the other inverter limits."
Now I don't have to restart Predbat, just call an automation to change the export power. Thank you :)

[uxbpncgw]

I have the export low power switch set to on but it doesn't seem to give me a snail or any extension to the period of discharge. I could set the apps yaml to a hard limit but I want it to remain able to do 7kw when there's an axle event.

…

On Wed, 9 Sept 2026, 14:13 Rob, ***@***.***> wrote: I have a self imposed export limit of 4000W. But I slow down the export by setting the Apps value *inverter_limit_export: 400* to 400W in my case. I use this low value specifically for the saving session slots just so I qualify for the free weekend hour. — Reply to this email directly, view it on GitHub <#4988?email_source=notifications&email_token=CNXRYQZHNREUXDPUJS7RD3D5OFJOXA5CNFSNUABIM5UWIORPF5TWS5BNNB2WEL2ENFZWG5LTONUW63SDN5WW2ZLOOQXTCOBTGY4DSNJSUZZGKYLTN5XKMYLVORUG64VFMV3GK3TUVRTG633UMVZF6Y3MNFRWW#discussioncomment-18368952>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/CNXRYQ5MO62TS6MM4OISO6L5OFJOXAVCNFSNUABIKJSXA33TNF2G64TZHM3DGNBUHA2TCMZWHNCGS43DOVZXG2LPNY5TCMBXGY4DMMJZUF3AE> . Triage notifications, keep track of coding agent tasks and review pull requests on the go with GitHub Mobile for iOS <https://github.com/notifications/mobile/ios/CNXRYQZ6UG4BMUA3375PNKL5OFJOXA5CNFSNUABIM5UWIORPF5TWS5BNNB2WEL2ENFZWG5LTONUW63SDN5WW2ZLOOQXTCOBTGY4DSNJSUZZGKYLTN5XKMYLVORUG64VFMV3GK3TUVJTG633UMVZF62LPOM> and Android <https://github.com/notifications/mobile/android/CNXRYQ5IZ222QEBKARMUNSD5OFJOXA5CNFSNUABIM5UWIORPF5TWS5BNNB2WEL2ENFZWG5LTONUW63SDN5WW2ZLOOQXTCOBTGY4DSNJSUZZGKYLTN5XKMYLVORUG64VFMV3GK3TUVZTG633UMVZF6YLOMRZG62LE>. Download it today! You are receiving this because you authored the thread.Message ID: ***@***.*** com>

[mark007]

Also interested in what the best approach is here. I have my sigenergy battery indoor and my understanding of reducing wear on the battery is where possible charge / discharge it slowly. The one place I can at least discharge slowly is at night between 11pm (when my import rate pretty much matches my export) and 2am when the cheap rate kicks in.

Id imagine a slower discharge from 11pm would reduce the temp increase on the battery compared to a full speed export. I turned on the low export power setting but can't get the snail to show up during these nightly exports. I also tried combine slots for export but it didn't help.

So interested to know whether ideally predbat should also add the snail here and reduce battery wear as part of its optimization logic. I'd hate to have to use automations in HA to get around it (mainly as I know if probably make a mess of things).

[uxbpncgw]

Would be good to know if it could be considered as a new feature or to change the logic. I've ended up putting a manual state of charge at 7pm of 70% and then it spreads the discharge rate slowly between around 6pm and midnight. Thanks, Alex

…

On Wed, 7 Oct 2026, 09:22 Mark Kennedy, ***@***.***> wrote: Also interested in what the best approach is here. I have my sigenergy battery indoor and my understanding of reducing wear on the battery is where possible charge / discharge it slowly. The one place I can at least discharge slowly is at night between 11pm (when my import rate pretty much matches my export) and 2am when the cheap rate kicks in. Id imagine a slower discharge from 11pm would reduce the temp increase on the battery compared to a full speed export. I turned on the low export power setting but can't get the snail to show up during these nightly exports. I also tried combine slots for export but it didn't help. So interested to know whether ideally predbat should also add the snail here and reduce battery wear as part of its optimization logic. I'd hate to have to use automations in HA to get around it (mainly as I know if probably make a mess of things). — Reply to this email directly, view it on GitHub <#4988?email_source=notifications&email_token=CNXRYQ6ASPFQDLXYH5YI26L5SVWDDA5CNFSNUABIM5UWIORPF5TWS5BNNB2WEL2ENFZWG5LTONUW63SDN5WW2ZLOOQXTCOBXHA2TINZTUZZGKYLTN5XKMYLVORUG64VFMV3GK3TUVRTG633UMVZF6Y3MNFRWW#discussioncomment-18785473>, or unsubscribe <https://github.com/notifications/unsubscribe-auth/CNXRYQYIWP7QBBLM6T4EAEL5SVWDDAVCNFSNUABIKJSXA33TNF2G64TZHM3DGNBUHA2TCMZWHNCGS43DOVZXG2LPNY5TCMBXGY4DMMJZUF3AE> . Triage notifications, keep track of coding agent tasks and review pull requests on the go with GitHub Mobile for iOS <https://github.com/notifications/mobile/ios/CNXRYQ6DDIFJPQMVDPMLGO35SVWDDA5CNFSNUABIM5UWIORPF5TWS5BNNB2WEL2ENFZWG5LTONUW63SDN5WW2ZLOOQXTCOBXHA2TINZTUZZGKYLTN5XKMYLVORUG64VFMV3GK3TUVJTG633UMVZF62LPOM> and Android <https://github.com/notifications/mobile/android/CNXRYQ67B6QT4IWHEEJL6FL5SVWDDA5CNFSNUABIM5UWIORPF5TWS5BNNB2WEL2ENFZWG5LTONUW63SDN5WW2ZLOOQXTCOBXHA2TINZTUZZGKYLTN5XKMYLVORUG64VFMV3GK3TUVZTG633UMVZF6YLOMRZG62LE>. Download it today! You are receiving this because you authored the thread.Message ID: ***@***.*** com>

[planetming]

Can I just add that although low power charging works, I've never seen the snail against a low power charge slot, only against Export slots. The tooltip shows the low power charge rate. Don't know if this is a bug?

[gcoan]

Can I just add that although low power charging works, I've never seen the snail against a low power charge slot, only against Export slots. The tooltip shows the low power charge rate. Don't know if this is a bug?

if the tooltip is showing a low power charge rate but the snail doesn't appear then this sounds like a display bug yes. You can see in the logs if slow rate charging or discharging is being applied, Predbat reports whether it can initiate slow rate charging and still meet the plan, so check this first

Also see my comment about switch.predbat_set_charge_low_power_solar_full_rate during the day

[planetming]

Here's an example. Tonight at 21:30. Max rate is 7.0kW. Tooltip shows 1.1kW
22:30 is also charging at the slower 6.2kW in the tooltip.

[gcoan]

Here's an example. Tonight at 21:30. Max rate is 7.0kW. Tooltip shows 1.1kW
22:30 is also charging at the slower 6.2kW in the tooltip.

thanks, that does look like a display bug so should be logged as a GitHub issue. please include screen shots, predbat.log and debug.yaml

[gcoan]

good you found the existing issue, looks like there is a fix pending that hasn't been merged yet

[mark007]

When I had been using predbat for weeks prior to my post, the slow export worked only during the day. It absolutely never kicked in at night to slow export before my nightly charge.

So the ask is to fix this I guess. As I have a workaround now it's not an issue for me and I am not sure if the behaviour I saw was fixed since. Maybe it has in which case there's no further ask.

Do you see slow export kicking in before a nightly cheap rate. If so I guess it's working. If you still see it planning to export at max speed sometime before the nightly charge you are seeing the behaviour we speak of.

[gcoan]

When I had been using predbat for weeks prior to my post, the slow export worked only during the day. It absolutely never kicked in at night to slow export before my nightly charge.

It should work as you expect it, once you turn it on all exporting will be evaluated as to whether it can do a slow rate export or not to meet the plan. If its not then worth raising as a bug for investigation

Slow rate charging is different. By default during the solar day, charging is always at full rate to avoid clipping solar, but overnight Predbat can throttle the charg rate. You can turn this of with a new control switch.predbat_set_charge_low_power_solar_full_rate

There isn't any similar time of day management for export