I have two 5kw inverters and I've configured the aux port on the master for non-essential loads (geysers, swimming pool pump).  The idea is that when the batteries are charged at 98%, then it can supply excess power to the non-essentials and if the batteries dip below 94%, then it should stop (either stop supplying power during load shedding or fall back to Eskom for non-essentials).  I've checked yesterday and when my batteries were at 93% SOC, it was still supplying power to the non-essentials from the batteries.

Is my configuration correct or am I misunderstanding how the "aux load output" is supposed to work?

On 2022/12/13 at 12:58 PM, ViperGTI said:

I have two 5kw inverters and I've configured the aux port on the master for non-essential loads (geysers, swimming pool pump).  The idea is that when the batteries are charged at 98%, then it can supply excess power to the non-essentials and if the batteries dip below 94%, then it should stop (either stop supplying power during load shedding or fall back to Eskom for non-essentials).  I've checked yesterday and when my batteries were at 93% SOC, it was still supplying power to the non-essentials from the batteries.

Is my configuration correct or am I misunderstanding how the "aux load output" is supposed to work?

Are you not using the grid tied mode where PV goes to the non essential from the normal operation side that what you see is not what is exported via the AUX port? 

It seems to be working now.  Well, at least while there is load shedding.  Once the batteries dip to 93% during loadshedding, then the plugs, geysers, etc. connected to the aux port loses power.

I think somehow this was related to the Hubble Riot module I had installed.  I replaced it with a Solar Assistant because the Riot wasn't working well with the multi-inverter setup and afterwards this started working and something else "broke", but that is also sorted now.

17 minutes ago, ViperGTI said:

It seems to be working now.  Well, at least while there is load shedding.  Once the batteries dip to 93% during loadshedding, then the plugs, geysers, etc. connected to the aux port loses power.

I think somehow this was related to the Hubble Riot module I had installed.  I replaced it with a Solar Assistant because the Riot wasn't working well with the multi-inverter setup and afterwards this started working and something else "broke", but that is also sorted now.

You've got the box ticked for "On Grid Always On." Try to untick that box, and then monitor the behaviour at times when the grid is on. If my thinking is right, it should then work as per the AUX function that you currently only see with loadshedding. Hope this makes sense.

Let me just check the behaviour one day when the battery dips to 93% when we don't have loadshedding and see from there.  Maybe everything is sorted now.

Green fields is correct with his statement about "On Grid always on". If that box is checked, the aux will always be on as long as the grid is connected. It will only default to the solar settings during load shedding. I found this excellent explanation by Craig Boswell (can't find where I downloaded it from) But

Sunsynk 8.8kW Hybrid Aux setup.pdf

Edited January 9, 20232 yr by Roy Wilson
Credit to author

Ok, I thought everything was sorted, but guess I was wrong.  If my batteries are above 94% and there is loadshedding, then the aux is powered and it disconnects as soon as the batteries reach 93%.  However, if the batteries are below 94% and Eskom is present, the aux load gets powered from the batteries instead of Eskom.

So to summarize:

• Batteries above 94% = Aux powered from the sun and/or batteries  (works as expected)
• Batteries below 94% during loadshedding = No power to aux  (works as expected)
• Batteries below 94% with Eskom present = Aux powered from batteries  (should be powered from Eskom)

Thanks @GreenFields and @Roy Wilson for the suggestions. I've now tried setting the "On Grid always on" to off, but then there is no power to the aux at night while Eskom is present.  I guess it would get power from the batteries if I set the solar threshold to 0, but that would defeat the purpose.  Not sure what this setup would do during the day, but it is this current timeframe / state that is the problem I want to solve since the rest of the time the system seems to work as expected.  Geysers and the swimming pool pump should always run off Eskom and only off of solar power once the batteries are full (up to 94%).  Technically the aux load should never be powered by the batteries so the last behaviour  on the list above seems a bit silly if that is the intended behaviour (given the behaviour of point 2).

On 2023/01/09 at 5:54 PM, Roy Wilson said:

Green fields is correct with his statement about "On Grid always on". If that box is checked, the aux will always be on as long as the grid is connected. It will only default to the solar settings during load shedding. I found this excellent explanation by Craig Boswell (can't find where I downloaded it from) But

Sunsynk 8.8kW Hybrid Aux setup.pdf 204.04 kB · 10 downloads

Excellent document, thank you.

I noticed the following two settings on the Sunsynk app that isn't on the inverter's display.  Wouldn't one of these resolve my issue?  Not sure what they do though.

(The two AC couple settings at the bottom)

There is a youtube video by sunsynk that says that the Solar Power shouldn't be set above 4000W - and that this value is basically the amount of power that the Aux port will be supplied with by the Inverter, ie out of your 8.8kW, only 4kW can go to the Aux port...If you set it to zero, according to them, you will not get any power feed to the Aux port. I'm more confused now than before. Seems in reality different things happening...

 

@ViperGTI Did you ever come right? I wonder if this might be an issue with parallel installs… are you running latest firmware?

 

On 2023/02/05 at 9:59 AM, boatmaker said:

There is a youtube video by sunsynk that says that the Solar Power shouldn't be set above 4000W - and that this value is basically the amount of power that the Aux port will be supplied with by the Inverter, ie out of your 8.8kW, only 4kW can go to the Aux port...If you set it to zero, according to them, you will not get any power feed to the Aux port. I'm more confused now than before. Seems in reality different things happening...

 

There’s so much confusion regarding Aux; it’s poorly documented.

The Solar Power figure has been found to indicate how much PV must be in use by the inverter to trigger the port. Thus if there’re no loads and the battery is full, a high figure here will stop the port from activating even on a sunny day.

For this reason it probably makes sense to set this value low (perhaps just below base-load, as a simple indicator of the presence of PV) and instead use battery cut-offs to determine if there’s sufficient sun to keep the port active (since the battery dropping indicates insufficient PV for the load).

 

This is clarified quite nicely in this thread:

 

@JayMardern What I ended up doing is to switch from off-grid mode to "on-grid" from 8am to 4pm and I make sure the geysers are on in that timeframe.  This seems to mostly work correctly.  If there is enough sun, everything will come from solar and if there isn't, it will draw from Eskom instead of shutting down.

I can't remember the behaviour now in the event that the geyser is on during loadshedding, but I think it will only drain the batteries until 94% and then turn off (like I wanted).  However, I manage the geysers manually so that it nevers runs off the battery.

The only issue I have running "on-grid" is that when loadshedding hits, the inverter has to switch from Eskom to batteries and that dip sometimes restarts my PC.  I've also had issues while I'm running a heavy load (i.e. over 4kw) and loadshedding hits, then it would sometimes make alarms go off and restart the inverters.  Both issues that I don't have if I just run plainly off-grid.

22 minutes ago, ViperGTI said:

@JayMardern What I ended up doing is to switch from off-grid mode to "on-grid" from 8am to 4pm and I make sure the geysers are on in that timeframe. 

Aaaah so you’re saying that the time slot had ‘Grid’ unticked in the System Mode-System1 screen - which forbids the inverter from pulling from Eskom at that time (those settings seem to take priority). This actually makes sense I guess.

 

Thanks for letting us know and shedding a bit more light on this otherwise cryptic Aux port!