Here's part of today's data from the Goodwe portal. Note how although load (yellow line) is light in the wee hours, it still uses some grid power (orange line).

Between 2 and 4 this morning we had load shedding, so the orange line goes flat, but everything keeps on running.

So, in the interests of squeezing the last drop of savings out of my system, is it possible to use the economic mode to force the system into using only battery from, say midnight until 5 am? The load is pretty constant and constantly low.

Eco mode might work, but I would advise against it. To me it looks like you are going below 150W at some points, and your inverter is designed so that below 150W, it disables the battery because the inverter itself will then be self-consuming a significant % of that 150W. So the best solution is to switch on a couple of things so that you are above 150W through the night - outside lights are always a good candidate.

On 2022/11/20 at 1:39 PM, P1000 said:

Eco mode might work, but I would advise against it. To me it looks like you are going below 150W at some points, and your inverter is designed so that below 150W, it disables the battery because the inverter itself will then be self-consuming a significant % of that 150W. So the best solution is to switch on a couple of things so that you are above 150W through the night - outside lights are always a good candidate.

Apologies for the late reply. It does look like that is what is happening, though the threshold may be a bit higher than 150W. 

The flip side of this, though, is that I'll use more battery overnight. But I'll give it a try and see what happens and how great the savings are.

42 minutes ago, Bobster. said:

though the threshold may be a bit higher than 150W. 

150W is about the threshold IME, but I suppose that could be dependent on the firmware version. This is from the manual:

On 2022/11/20 at 1:18 PM, Bobster. said:

is it possible to use the economic mode to force the system into using only battery

you could have a timer controlled contactor in the DB to create your own loadshed/disconnect from commercial power between the times you want...

1 hour ago, P1000 said:

150W is about the threshold IME, but I suppose that could be dependent on the firmware version. This is from the manual:

LOL. I should have read the fine manual.

Hard to pinpoint exactly on SEMS, but it is south of 200W.

Edited December 5, 20223 yr by Bobster.

1 hour ago, Kalahari Meerkat said:

you could have a timer controlled contactor in the DB to create your own loadshed/disconnect from commercial power between the times you want...

Well that covers my outside lights. Whether they'll increase the load by enough remains to be seen (mix of LED and CFL).

I should have kept that fridge that never turned off.

Well I ran the outside lights last night. Most of them are activated by photo cells, which is just as well, because the timer isn't working (it's the type with a dial that should be turned by the 50Hz, but it doesn't advance). This added a huge 50W to the load. Hard to know how much difference it made because we had load shedding from midnight until 02:30. But after about 2:30 we see the draw from grid again. So maybe a bit more is needed.

 

At 4:15 the load is 236.5 W and the system is drawing 247 from grid, despite their being plenty of battery. From 2:20 to 2:45 is is drawing a steady 180W. But SEMS is coarse data. Samples every 5 minutes

I'm averaging about 1.5 units per day. This, of course, is totally unacceptable, and the sort of thing about which government does nothing even though it can ruin a fellow.