I am trying to improve on the settings for utilising the relay option to start up a pump when there is excess solar power. I am able to start a well pump by opening up a solenoid valve through the use of 'relay 1' on the VenusGX. This is great as I am able to start the pump only during certain times of the day and also when there is excess solar available. The settings that I am using at the moment are:
1. 'Relay 1' uses the 'Generator start/stop settings';
2. Use 'AC load' as a 'Condition' to open up a solenoid valve;
I currently have the solenoid close when the total consumption is higher than 50W for at least 600s (this avoids opening and closing the solenoid too often on partially cloudy days). I open up the solenoid when the total consumption is lower than 0W for an hour. As the total consumption is less than 0W I know that the batteries are fully charged. This means that I am certain that there is excess power being fed into the grid and therefore there is power that can be utilised elsewhere. Unfortunately I am not able to determine how much excess power I have and therefore the 1kW well pump might be starting when there is only 100W of excess power.
Victron staff, is it possible to have the values for setting 'Stop when power is lower than' under 'Generator start/stop settings' > 'Conditions' > 'AC load' > to a minus figure? That way you can start bigger pumps/heaters when the excess load is closer to the rated power requirements of the pumps/heaters. Effectively what you then are creating is a unit that has similar functionality as other units like the Fronius Ohmpilot.