Why is Sol-Ark 15k pulling/sending short energy spikes from the grid

[Patel]

Hi everyone,

Recently installed my Sol-Ark 15k about 2 weeks ago. Today I got around to installing Solar-Assistant, and wow what an amazing software. I recommend it.

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One question that I have,
I noticed from both my energy company data, and the Solar-Assistant data, the Sol-Ark is pulling and sending energy spikes to and from the grid.

I have zero export power enabled, and set to 20w.

I am running (4) BigBattery Kong Elite 15kwh in parallel. So there is no shortage of battery capacity to handle the loads. The spike in the attached screenshot is from turning on the stove. It created a short spike from the grid for about a second, and then the rest was powered by the batteries.

My goal is to eliminate grid usage, unless absolutely necessary. And I don't want to send any energy to the grid because I do not have a interconnection to sell to the grid.

Anyone have any ideas why this is happening? Maybe some settings that need to be changed? I have uploaded pictures of my battery and grid settings.

Thank you!

 

[dianea]

I have zero connection to the grid, zero volts, no wires on the grid terminals, but Solar Assistant is showing the same thing on my Growatt 5000. Not sure how the number is calculated...

 

[Patel]

I have zero connection to the grid, zero volts, no wires on the grid terminals, but Solar Assistant is showing the same thing on my Growatt 5000. Not sure how the number is calculated...

That's nice to hear.

You get both spikes and negatives on the grid chart like i'm describing?

 

[dianea]

That's nice to hear.

You get both spikes and negatives on the grid chart like i'm describing?

Yes, and appears to happen when the load changes when PV is charging . Doesn't appear to happen at night when PV is zero.

Interesting it shows "grid power" activity, yet grid frequency and voltage graphs both show a flat, steady zero.

 

[zanydroid]

Are those happening when loads come on/off?

Zero export is not magic. It has a response lag proportional to however long the CPU takes to detect and then push down correction to the current export deviating from zero. And typically these things will calculate the accumulated error and make some compensating import or export to cancel it out later.

 

[Patel]

Are those happening when loads come on/off?

Zero export is not magic. It has a response lag proportional to however long the CPU takes to detect and then push down correction to the current export deviating from zero. And typically these things will calculate the accumulated error and make some compensating import or export to cancel it out later.

yes, they seem to be coming when loads turn on and off

 

[Skypower]

Just shooting into the dark here, could the wires running to the CT’s be running next to a cable that’s carrying a lot of current and the sensor’s wires are inductively picking it up? Can you move the wires at least temporarily to see? I’m running two Lv6548’s which don’t have external CT’s and my grid is flatline on Solar Assistant unless I’m using from grid. Yeah I know totally different animals and leagues.

 

[629658]

I don’t see that in my 15k. I’m in limited to home mode, zero export 20w, Solar sell checked, battery first.

 

[Patel]

Using PV Pro instead of Solar Assistant, it also shows -50W from the grid.

I called SolArk support today, we updated the inverter, double checked all the settings too.

If grid is showing -50W, does it mean that it's being exported?

 

[Patel]

Could it be because CT sensors are not installed?

 

[LydMekk]

Check the direction of your CT.

 

[robby]

yes, they seem to be coming when loads turn on and off.

I have CT sensors installed and based on your other post I assume you do not have them installed?
My 12K does not push power back to the Grid when the load goes off but it definitely pulls a small amount of the needed power from the Grid for a few seconds when a heavy load is turned on.

As @zanydroid stated this is power the Sol-Ark uses to make a smooth transition during a sudden demand.
If you were off grid it would probably cause a small Sag in the voltage but since it see's grid power it uses it to keep things stable until it can do the calculations and ramp up the power from the MPPT or add more battery power.
The major part of the delay is caused by the MPPT's ramping up or switching over from charging batteries to AC production.
At night when your on Battery it has just about an unlimited supply of instant power already on Tap, so it does not need to use the Grid so there is no AC usage.