Is it possible to set the maximum battery charge when charging from grid?
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- Posts: 1873
- Joined: Thu Sep 09, 2021 3:42 pm
- Location: North East Dorset
Re: Is it possible to set the maximum battery charge when charging from grid?
This is indeed valuable information. I would be as frustrated as heck if I wasn't able to set an upper SoC limit when the inverter is in time of use mode. It's absolutely key to being best able to utilise as much PV generation as possible, whilst ensuring that there is just enough charge put in overnight at the cheap rate to cover our needs should the following day prove to be poor in terms of PV generation.
25 off 250W Perlight solar panels, installed 2014, with a 6kW PowerOne inverter, about 6,000kWh/year generated
6 off Pylontech US3000C batteries, with a Sofar ME3000SP inverter
6 off Pylontech US3000C batteries, with a Sofar ME3000SP inverter
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- Posts: 126
- Joined: Wed Oct 05, 2022 11:48 am
Re: Is it possible to set the maximum battery charge when charging from grid?
Regarding Solis inverters, there is a way to work around the lack of a max SOC option, but it is quite a lot of work...
Right now, I have a RS485 to wifi converter connected to my solis hybrid, allowing me to read and write modbus registers directly.
I use Node Red to handle the modbus connection, then combine it with an adjusted Solcast forecast (shading is an issue, especially at this time of year) and historical household energy consumption.
There's a whole bunch of data jiggery pokery that spits out a required SOC to make it to the end of the day at no lower than 20%, which is then used to automate the activation and deactivation of 'scheduled charge & discharge' on the inverter.
For example, last night the calculations suggested 60% would be needed to make it through the day at no lower than 20%.
The battery was at 54% at 00:30, so the inverter was instructed to start charging during off-peak. As soon as it got to 61% SOC, the inverter was instructed to stop scheduled charging.
It's a fair bit of work to set up, but it's been hands off since I set it up in September. If there's interest, I can put together a guide on a new thread.
Of course, it would be a lot simpler if Solis implemented a target SOC option...
Right now, I have a RS485 to wifi converter connected to my solis hybrid, allowing me to read and write modbus registers directly.
I use Node Red to handle the modbus connection, then combine it with an adjusted Solcast forecast (shading is an issue, especially at this time of year) and historical household energy consumption.
There's a whole bunch of data jiggery pokery that spits out a required SOC to make it to the end of the day at no lower than 20%, which is then used to automate the activation and deactivation of 'scheduled charge & discharge' on the inverter.
For example, last night the calculations suggested 60% would be needed to make it through the day at no lower than 20%.
The battery was at 54% at 00:30, so the inverter was instructed to start charging during off-peak. As soon as it got to 61% SOC, the inverter was instructed to stop scheduled charging.
It's a fair bit of work to set up, but it's been hands off since I set it up in September. If there's interest, I can put together a guide on a new thread.
Of course, it would be a lot simpler if Solis implemented a target SOC option...
10x 405W JA Solar panels (4.05kWp) @ 5 degrees
3x 405W Longi panels (1.22kWp) @ 90 degrees
16.5kWh DIY LifePo4 battery
Solis inverter/charger
0.6kW Ripple WT
64kWh Kia E-Niro
3x 405W Longi panels (1.22kWp) @ 90 degrees
16.5kWh DIY LifePo4 battery
Solis inverter/charger
0.6kW Ripple WT
64kWh Kia E-Niro
Re: Is it possible to set the maximum battery charge when charging from grid?
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Last edited by marshman on Sun Jun 11, 2023 2:48 pm, edited 1 time in total.
Re: Is it possible to set the maximum battery charge when charging from grid?
At the moment I use an Elfin EW11, you can get them very cheap if you don't mind waiting a while for delivery.
My particular setup uses an already running server for home automation, but it should be pretty straightforward to do something more standalone, using a raspberry pi, RS485 adaptor and software like Node Red for the automation.
I'll get my notes together and post it up in a separate thread.
10x 405W JA Solar panels (4.05kWp) @ 5 degrees
3x 405W Longi panels (1.22kWp) @ 90 degrees
16.5kWh DIY LifePo4 battery
Solis inverter/charger
0.6kW Ripple WT
64kWh Kia E-Niro
3x 405W Longi panels (1.22kWp) @ 90 degrees
16.5kWh DIY LifePo4 battery
Solis inverter/charger
0.6kW Ripple WT
64kWh Kia E-Niro
Re: Is it possible to set the maximum battery charge when charging from grid?
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Last edited by marshman on Sun Jun 11, 2023 2:48 pm, edited 1 time in total.
Re: Is it possible to set the maximum battery charge when charging from grid?
I'm just tidying up my standalone Solis hybrid control logic in Node Red flow, hoping to get it finished and shared on the forum.
I do have one question though, for those who have SOC target already on their inverter, what exactly does it do?
Does it:
- Charge up to the target (80% for example), stop charging and then immediately start discharging to the house load?
- Charge up to the target, stop charging and doesn't discharge to the house load until the scheduled period is over?
- Or something else I hadn't considered?
I do have one question though, for those who have SOC target already on their inverter, what exactly does it do?
Does it:
- Charge up to the target (80% for example), stop charging and then immediately start discharging to the house load?
- Charge up to the target, stop charging and doesn't discharge to the house load until the scheduled period is over?
- Or something else I hadn't considered?
10x 405W JA Solar panels (4.05kWp) @ 5 degrees
3x 405W Longi panels (1.22kWp) @ 90 degrees
16.5kWh DIY LifePo4 battery
Solis inverter/charger
0.6kW Ripple WT
64kWh Kia E-Niro
3x 405W Longi panels (1.22kWp) @ 90 degrees
16.5kWh DIY LifePo4 battery
Solis inverter/charger
0.6kW Ripple WT
64kWh Kia E-Niro
Re: Is it possible to set the maximum battery charge when charging from grid?
For my Luxpower it's this one. Once at SOC limit, the batteries sit idle until the period is over, then start discharging.MrPablo wrote: ↑Fri Oct 21, 2022 9:03 am I'm just tidying up my standalone Solis hybrid control logic in Node Red flow, hoping to get it finished and shared on the forum.
I do have one question though, for those who have SOC target already on their inverter, what exactly does it do?
Does it:
- Charge up to the target, stop charging and doesn't discharge to the house load until the scheduled period is over?
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- Posts: 1873
- Joined: Thu Sep 09, 2021 3:42 pm
- Location: North East Dorset
Re: Is it possible to set the maximum battery charge when charging from grid?
Same here for my Sofar ME3000SP. That's set to charge to the SoC target and not supply any battery power for the whole off-peak slot. Means we can charge the car overnight in winter with no risk that the battery will provide part of the car charge. Also means that when we get to the point where the heating comes on overnight, that can run on off-peak electricity without using any energy from the battery.Caesium wrote: ↑Fri Oct 21, 2022 9:05 amFor my Luxpower it's this one. Once at SOC limit, the batteries sit idle until the period is over, then start discharging.MrPablo wrote: ↑Fri Oct 21, 2022 9:03 am I'm just tidying up my standalone Solis hybrid control logic in Node Red flow, hoping to get it finished and shared on the forum.
I do have one question though, for those who have SOC target already on their inverter, what exactly does it do?
Does it:
- Charge up to the target, stop charging and doesn't discharge to the house load until the scheduled period is over?
25 off 250W Perlight solar panels, installed 2014, with a 6kW PowerOne inverter, about 6,000kWh/year generated
6 off Pylontech US3000C batteries, with a Sofar ME3000SP inverter
6 off Pylontech US3000C batteries, with a Sofar ME3000SP inverter
Re: Is it possible to set the maximum battery charge when charging from grid?
Great, thanks for confirming!
10x 405W JA Solar panels (4.05kWp) @ 5 degrees
3x 405W Longi panels (1.22kWp) @ 90 degrees
16.5kWh DIY LifePo4 battery
Solis inverter/charger
0.6kW Ripple WT
64kWh Kia E-Niro
3x 405W Longi panels (1.22kWp) @ 90 degrees
16.5kWh DIY LifePo4 battery
Solis inverter/charger
0.6kW Ripple WT
64kWh Kia E-Niro