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by kkfx 864 days ago
Feeling the frustration of owning a Victron EVC300400300 "integrated" with my p.v. (WFH, so I can recharge my car during many days) I've used a ShellyPro 2 to power on a small 2kW resistive heater for few minutes, drop the load and power cycle the EVC.

VERY often this device in "auto mode" (charge from p.v. varying charging current following maximum p.v. production) in a zero-injection to the grid setup decide there is not enough p.v. power available even if it's totally false. Since Victron have not added a "force start" option I have done mine. When the EVC see the extra power available just after restarting it star charging...

A very good example of the crappiness level and logic of actual IoT... Another simpler automation is for my VMC (AirWell AirFlow 250-N91, witch I discover that's also Clivet ElfoFresh and other names, since it's a Chinese machine rebranded by some integrators in various country) that in auto mode when there is a very sunny winter day with mild temperature and the home due to the southern large windows start to heat way too much it keep running the compressor injecting absurdly hot air instead of passive cooling. The automation is simply ModBUS via HA to switch from auto to "ventilation only" and switch back if the outside temp goes lower than 7℃ since the VMC refuse to ventilate below 7... Even if I have 25 inside.

Another of the same kind for my domestic hot water heater, Daikin/Rotex M2O EKHHP "a machine for the future in the present, ready for renewables" etc etc etc that's so ready that the sole automation available are 2 dry contacts that allow to

- run full power till the water reach a certain threshold (that I can't set, 62℃ hard-coded)

- run the compressor (heat pump only) for an hour than the resistive heater + the compressor

- do not run

- decide autonomously what to do

Daikin engineers have essentially not counted p.v. in their design but just different grid tariffs during a day. There is no way to tell something like

- do not run

- run ONLY the resistive heater (following water temperature, of course)

- run ONLY the heat pump

- run both

Way too simple apparently for their mind... As a result when I have enough spare p.v. HA flip between the "do not run" and "run the heat pump than also the resistive heater" every 15' to keep just the heat pump. Run full power if there is more spare power, but no way to tell, run just the resistive heater (2kW instead of 2.6-2.8kW). It's nothing special in economical terms, just my desire to optimize self-consumption, but the design of ALL current IoT appliance are obscene and demand obscene hacks to use then rationally simply because their designer never though nor about integration, nor about a vast set of real world scenarios.