Charging from the grid overnight - drawing too much power

[steveoracle]

Hi all,

Anyone got any ideas or advice on this issue.

I recently went on to a cheap overnight tariff with the idea of charging my battery overnight for use during the next day. I have a Growatt 6.5kWh battery and hybrid inverter. So I set the system to charge overnight. So I've been monitoring consumption over the last week or so and I've noticed that the system is drawing more than it should when it charges the battery. So for e.g. if the batter is fully discharged (90% DOD) it should need ~6.0kWh to fully charge and it's actually drawing more like 7.5kWh during the charging period. I've changed up the charge rate, charge level and timings and it seems te constantly overdrawing whatever I do. I've noticed that there's a weird tail in the consumption charts - see below.



Any ideas, advice or experience in this?

Cheers,

Steve

 

[AshleyL]

? Change Program 11 to 0Amp or 1Amp.

Oh wait, I re-read again and you can adjust the amperage at Program 11 to suit your need.

Battery voltage x amperage = watts

 

[millsan1]

Conversion efficiency.
Assuming 90% efficiency into and out of batteries:

7.5 drawn = 6.75 into battery
6.75 out of battery = 6

 

[400bird]

Does that graph also include you other loads? As in 6.75 kW to charge the battery and 0.75kW to power the house?