I lowered my contracted grid power. Now the EV charger plus an iron and a heater trip the utility meter. Can my Deye hybrid cover the peak from the battery instead? And why did the battery go below my 30 % setting?

Plain explanation

The Deye SG05LP1 manual describes 'Grid Peak-shaving': when it is on, power drawn from the grid is held within a set value, and if the house needs more, the inverter adds PV and battery power. Only if that is still not enough does grid power rise above the limit. Set it a little below your contracted power, so the inverter covers short peaks like an iron or a heater before the utility meter trips. There is also an 'Import power limiter', with lower priority than peak shaving. In 'Time of use' you set the battery SOC at which each discharge action happens. That is why the battery stopped at 30 % while the grid was there. When the meter tripped, the inverter went off-grid, and the manual's battery settings show a separate 'Shutdown' SOC at which the inverter switches off. That explains why it kept discharging below 30 %. The manual does not say whether peak shaving will discharge below the time-of-use SOC, so test it with a known load. Check the inverter's continuous rating before relying on it for heavy loads, and have the installer set the limits.

Steps from the source

1. Note the contracted power and convert it to a grid import limit with some margin
2. In the system work mode, enable Grid Peak-shaving and set the power just below that limit
3. Check Time of use: the SOC per time slot is the floor for on-grid discharge
4. Check the Battery Setting values: Shutdown / Low Batt / Restart SOC apply when running off-grid
5. Keep large loads like EV charging in off-peak hours or on a timer

"Grid Peak-shaving: when it is active, grid output power will be limited within the set value. If the load power exceeds the allowed value, it will take PV energy and battery as supplement. If still can’t meet the load requirement, grid power will increase to meet the load needs."

Word for word from the source.

Source

Where installers ask this

• Self-consumption PV megathread, page 245 (forumdacasa.com)
• https://forumdacasa.com/discussion/94250/245/paineis-fotovoltaicos-para-auto-consumo-4/

General guidance based on the manufacturer's manual or the named source. Always follow the current manual for your exact model and your national code. DC and AC electrical work is for qualified installers only. Not affiliated with or endorsed by any brand named; trademarks belong to their owners.