Lets look at the pro’s and cons with what you already have and a simpler way.
Option 1 Inverter-
You could set the battery SOC to 100% in the time of use setting, but at the same time, dont select grid charge time. If at the time the pv battery is less than 100% then the battery will not discharge at all preventing the battery discharging to the car.
Another Inverter option, is to ensure yourpv batteries are set to charge during the off peak time period, by setting a SOC% you would like the batteries to charge up to.
The disadvantage of this, is with intelligent tariffs and the off peak window they give outside of the normal off peak window hours. Off course this would be an advantage with non intelligent tariffs, such as EON next drive, where you are given one off peak window. Are you following😂
**Perhaps the best amd easiest option (CT clamp location)
Depending on positioning of CT clamps, your PV batteries, could see the charger as just another load, so every time you plug in the car or during extra hours on IO, the house battery detects the demand and start to discharge to meet it.
To overcome this, the pv battery CT needs to be positioned downstream of the charger, this puts the charger outside the monitoring zone. Then the battery won’t detect the charger load and won’t discharge, preventing unwanted battery drain during times you charge your car.
This way is simple ro do as CT’s just unclip and you can relocate them, although your system maybe setup this way anyway (we can look into that) and the charger basically sits on it’s own away from you PV system and charging the car won’t affect anything, as you will just charge during IO hours.
Hypervolt chargers have whats known as “Battery Safe” mode, in the event of solar surplus, say you wanted to charge the car from that surplus, you would still find it discharging the PV battery. To overcome this problem, Hypervolt introduced this new charging mode. Primarily it’s designed for those who want to charge their car using only surplus solar energy, whils’t saving battery capacity for other uses.
I don’t think this option is for you as you sell back for a higher price than you can charge during off peak hours. However, for those that may find it useful –
https://support.hypervolt.co.uk/en/knowledge-base/home-battery-system-setup
**This option maybe just what your looking for 🙂
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