Hi All

I am new to the forum and this is officially my first post. 🙂

This week I had my PV system installed which includes an 8kW Deye hybrid inverter, 16 x 540W JA panels plus 3 x 5.1 kW Shoto batteries. 

I did quite a lot of research on the Internet (including a ton of reading on this forum) regarding the inverter. One of the features that really attracted me to the Deye (and I suppose the Sunsync as well) is the ability to run my geyser off the AUX port known as the "Smart Load" feature.  From what I have read, the AUX port/smart load would allow me to manage the operation of my geyser with a bit more intelegence when compared to simply connecting it to the GRID connection on the inverter (non-essential side, after the CT coil) 

From all the info I have read on the web (including this post on the Sunsync forum https://www.sunsynk.org/forum/techical-support/using-the-aux-output-on-8kw-hybrid), I understood the operation of the AUX port as follows:

There are three settings that drive the AUX port, the battery SOC where the AUX load should become active, the battery SOC where the AUX load should be turned off and the minimum required PV power available at which the AUX load should be turned on... So basically I can set it up like this 

If more than 3500W is available on my PV (I have a 3kW geyser) and my battery has a SOC greater than 95%, then turn on my geyser und run it until either the PV power drops below the set 3500W or my battery SOC drops below 80%.

However, after playing around with these settings on my Deye today, it seems as if the flowing is actually how these settings work. 

When my battery SOC is greater than the set value (i.e. 95%) and my inverter IS ALREADY DRAWING 3500W OR MORE FROM PV, then only will it turn on the Smart load (AUX port). This then means that when my geyser on the AUX port is turned on, the total load on the inverter often exceeds what is available on PV and I have to dip into my batteries to run the geyser (something I want to try and avoid). 

Today I tested this as follows. I knew that there was in excess of 4kW available on PV even though my inverter was only having to to supply our base load of around 300W. With the battery at a SOC of more than the set 95%, the AUX load would only turn on after I reduced the PV power "switch on" value to below the value that the was currently drawn by my inverter, not the power that is potentially available on PV... 

Can anybody elaborate on this, is this how the feature is supposed to work, is there a wrong setting on my inverter setup or am I missing something? I would prefer if the system works the way I had originally understood it... Only turn on my geyser if available PV can supply more power than what my geyser draws.

Thank you in advance! 

Regards, 

58 minutes ago, Freakazoid said:

When my battery SOC is greater than the set value (i.e. 95%) and my inverter IS ALREADY DRAWING 3500W OR MORE FROM PV, then only will it turn on the Smart load (AUX port). This then means that when my geyser on the AUX port is turned on, the total load on the inverter often exceeds what is available on PV and I have to dip into my batteries to run the geyser (something I want to try and avoid). 

Hi Freakazoid with my bit of playing around I have seen battery power will be used when PV suddenly drops to below the set value due to clouds passing over. If PV does not recover within 1 minute smart load will switch off, but by than you have already used that 1 minute of battery power.

Than again conditions need to improve for at least 1 minute before smartload switches on. I am using smartload to run a cooling fan on my inverter and a fresh air ventilation fan in my garage and I can hear the fan start and stop with clouds moving over. My settings for SOC and PV is pretty low because I want the fans to run most of the day even with a low SOC so I could not notice any drop in SOC due to fans only drawing about 52W. 

Only thing I did not check is the tick-box at setup page for “ongrid always on” not sure how that work.

Hi Freakazoid, I have the same inveter. A wiring mistake put my geysers (and oven) on essential. I quite liked having the geysers on essential, but only because I also have Geyserwise timers so I can time them to boil up in sequence from 11:00 to 14:30, when there should be excess solar.

When they came to fix it the guy put my oven on Aux (non-essential as he calls it). After a couple of days (and lots of agitated discussion) it was moved to non essential after CT where it should have been in the first place.

The days I had the oven on Aux told me it is more trouble than what it's worth. I'm happy with my binary essential / non essential split, leaving the Aux port for generator use when it becomes necessary.

 

 

 

I have a 5kw Sunsynk and have my geyser on aux. I primarily heat my water with a heat pump to 60 degrees  and then the geyser to 70 degrees Celsius. The Aux works well enough if its a clear day. It will use battery up till the specified SOC before turning off the AUX port.

Sometimes the AUX port wont be turned on even with excess PV, i usually just turn on the kettle briefly and that wakes up the aux port. I think the inverter has no way of knowing how much excess PV is available unless if you put a load that triggers it. 

i was one of the first ones to post on the forum regarding the AUX feature, never got it to work properly, so gave up on it and have not been able to get Sunsynk to look in the problem

Thanks @Gerrie, yes, I understand that while the Smartoad (AUX port) is active, the system will dip into the batteries for short periods of time when the PV can't supply the entire load. I am happy with this, I just don't want the geyser to run off batteries only for 45 minutes... 

@Scubadude, yes, I can imagine that having an oven run on the AUX port won't work well as you need to run the oven "on demand" where as a geyser I just need to heat up sometime between 8:00 and 15:00 so that I have enough hot water for the evening and next morning. This is supposedly how the AUX port is intended to be used. The AUX port can be forced to be permanently on (if grid is available) by selecting the "On Grid Always On" options but this then allows the load connected to AUX port to drain the battery to your SOC values specified in the "Time of Use" or general battery settings, it ignores the AUX Off battery SOC value as well as the PV power values. The nice thing is, unlike the non-essential loads on the Grid port, the AUX load can be set up to work when there is no power on the grid side (i.e loadshedding).

@phidzYes, your use-case is exactly what I noticed on my system too... The AUX Load doesn't "know" what power the PV can provide and therefore the PV power value you set for the AUX port first needs to be drawn by something else on your system before the AUX Load will switch on... This is my issue as this is not how the manual explains it and not really how I want to use it... 

As @Tariqsays, doesn't look like Deye or Sunsync can give us an official answer as how to use it. In fact, Keith from Sunsync explains in one of his videos that the PV power value specified on the AUX setting page is the maximum power that the AUX port should supply which is definately NOT correct. Seems like he himself doesn't really understand the workings of it... 

@CraigB, sorry to randomly tag you in this post but I assume that it was you who posted a similar question in the Sunsync forum a while back? Can you perhaps give us some feedback on your experience with the AUX port or any additional info you have managed to find? I know you wrote a short document discussing 2 different use cases for the AUX port which is very helpful! 

 

In my opinion the aux load has it’s challenges to integrate into a DB board, it will need to be done and treated as a separate essential section of the DB. The aux load is a very nice function if you can find a correct use for it as long as your installation is still SANS compliant when using it. The electrician doing the C.O.C need to look at the following.

1. Does the earth leakage still protect your geyser when Aux load is used?

2. How do you wire geyser on non-essential side for rainy days and also be able to use it when excess PV is available still protected by earth leakage?

The aux loads primary function was probably designed as a generator input and the mere fact that it can also drive non-essentials loads like geysers does not make it the ideal way to heat water. I use aux for cooling purpose with a inline fuse on the fan circuits because I don’t need earth leakage protection for my double isolated fans. This is just me looking at compliance side of things.

Hi @Gerrie and everyone else.

I am not an electrician so forgive the possible silly question, but would a changeover switch make sense to use with the aux load feature?

So for position A of the changeover switch, the geyser/stove/non-essentials are before the inverter, therefore are not connected to the aux port of the inverter. Excess PV can still be used to reduce the costs of the non-essentials. However, in this position, if grid goes out, the inverter cannot power the non-essentials. The advantage though is that the non-essential loads to not count towards the inverter load limit (for example, 5kW on the 5kW inverter).

For position B of the changeover switch, the non-essentials are then transferred to the aux port of the inverter. Excess PV can still be used to decrease the costs of the non-essentials. However, in this position, when there is no grid, the non-essentials can still run under "favourable conditions" aka inverter aux settings, but the non-essentials now count towards the inverter load limit (eg 5kW) so one must be extra careful to not overload the inverter.

Position B would be used during load shedding / major outages and one would need to watch the inverter usage closely. Position A would be used at all other times.

What do you think of the above?

6 hours ago, SolarConvert said:

I am not an electrician so forgive the possible silly question, but would a changeover switch make sense to use with the aux load feature?

I was taught there is no silly question, those questions that others might think is silly, is the exact ones I learn the most from.😁

In my opinion a changeover switch will work for that purpose as you describe, as long as your AUX load settings like battery SOC and the solar PV settings are within start-up range for smart load to function. 

You would just need to give a bit of extra attention to the wiring diagram from AUX load, as to maintain safety like earth leakage protection on equipment when it is switched over to position B.

Personally I don’t think it is the best way of running non-essentials from inverter when Eskom is down. I would rather install a changeover switch on the non-essential side as-well, that will also allow you to switch over when Eskom is down. That is how my DB is wired, with two change over switches but you than have to also monitor battery not to be drained to quick.

Thanks! And you are correct, my goal is to run non-essentials from the inverter when the grid is down and the AUX/smart load feature looked interesting.

AUX feature aside, I actually did want a second changeover switch added when my 5kW Deye system was installed but got convinced by the electrician and the installer to not do this. The electrician asked me to draw a diagram of what I wanted and after I had (rather poorly) drawn the diagram, he said he needed to think about it and would rather come back at a later stage to do this if the installer gave the green light. I basically wanted the second changeover switch to convert the non-essentials to essentials so that the induction hobs that I have (and love) could be used during a grid outage. The installer vehemently objected to this citing that the hobs would bring along the oven (same circuit) and I can easily overload the inverter this way. Using a changeover switch to transfer non-essentials to become essentials amplifies the risk of too many things being be turned on at once, he said. I do not disagree with him and understand his perspective, but still maintain that in emergency situations where we have had several days of grid outage on multiple occasions, it would be a conscious decision to temporarily convert non-essential loads to essentials using the changeover switch and very carefully ensure that the inverter is not overloaded. After all, being able to cook on the induction hobs at medium strength only uses around 700-800 watts, though admittedly someone can boil the kettle on the max setting and use 3kW of power, there is nothing stopping them. That is why currently the hobs and oven are non-essentials. Of course, different solutions to this problem do exist, such as installing gas hobs or buying a bigger inverter, but it is very rare that we ever exceed 5kW usage whilst there is Eskom power (essentials + non-essentials combined) on the inverter and it still appears to me that a changeover switch for emergency situations is the most cost-effective and practical solution to using non-essentials when the grid goes down.

So then there would be the two options of running non-essentials during a grid outage using a changeover switch, if the above is correct:

1. A changeover switch transfers non-essentials before the inverter to essentials on the inverter (this is the diagram I tried to unsuccessfully draw), or
2. A changeover switch transfers non-essentials before the inverter to the AUX port of the inverter

I agree that with option 1 you would need to monitor that your battery does not get depleted, but apart from that you do not need to make any inverter setting adjustments - the non-essentials will always work once changed over.

With option 2, if there is insufficient PV or the battery SoC is too low based on the AUX settings, then the AUX loads will not power on and similarly if there is sufficient PV + battery to power the AUX loads initially, they will be powered down (I assume) as soon as one of the two factors drop below the defined thresholds. At which point one can probably walk to the inverter and lower the thresholds if need be. I initially thought of these thresholds as a possible safety feature to not deplete the battery below a certain threshold, which allows you to preserve the battery just for essentials (the installer guy also likes this extra protection), but if in practice one would always walk to the inverter and lower the AUX thresholds when needed, perhaps then you are right, one may as well just have gone with option 1 for this use case in the first place.

Note I have not taken any action yet on the above, I am trying to figure out what the best option is for this use case and this thread made me think that AUX is an option.

59 minutes ago, SolarConvert said:

I initially thought of these thresholds as a possible safety feature to not deplete the battery below a certain threshold, which allows you to preserve the battery just for essentials

You have a valid point that aux function can be set to preserve the battery when it reaches let’s call it the “lowest allowable SOC” 

In other words you could set Aux load to always be “on”. And it should only switch “off” when lowest allowable SOC is set for example to 40%. That last 40% is than strictly preserved for essential loads. 

The aux load has some merit if you can find the right use, it could possibly even be integrated into home automation or something where SOC and solar PV levels could come in handy.

On 2021/12/17 at 11:23 AM, phidz said:

Sometimes the AUX port wont be turned on even with excess PV, i usually just turn on the kettle briefly and that wakes up the aux port. I think the inverter has no way of knowing how much excess PV is available unless if you put a load that triggers it. 

If you have "Zero Export" un-ticked, i.e. you export excess power to the grid, this feature should work correctly.

Why SunSynk and Deye don't upgrade the firmware controlling the MPPT's to provide the potential / available solar is strange?

To limit the supplied load to actual load, the MPPT's are dialed back by a known amount, which can be calculated and displayed as potential power, and used for AUX port control too. 🤔

 

Hi everyone, sorry for reviving a bit of an old thread but I need some clarification and advise. I'm pulling the plug on going solar and the plan is to go with 8k Deye Inverter, 19 x 545w panels with 4 x 5kw batteries. I was thinking of putting my geyser (3kw element) and oven (only oven because I got gas hob) on smart load. The rest of the entire house on essential load. Pretty much nothing on non essential load. I currently have my geyser connected to a geyser wise and I don't want to change that. So my questions are:

1. With the geyser on smart load, whether we have grid power or not, would the geyser wise always be on regardless of whether we have the element activated or not?

2. Would putting the oven on smart load be a good idea? I don't want to be in a scenario where the oven was switched on but it goes off because PV is not enough and battery SOC is lower than the 'off' setting but we still have eskom?

3. If you have "on grid always on". Is the order of preference

PV -> battery -> grid

or

grid -> PV -> battery?

 

Hope I've given as much information as possible to give everyone enough context.

Edited August 7, 20222 yr by isie

On 2022/02/02 at 11:39 PM, TimCam said:

If you have "Zero Export" un-ticked, i.e. you export excess power to the grid, this feature should work correctly.

Why SunSynk and Deye don't upgrade the firmware controlling the MPPT's to provide the potential / available solar is strange?

To limit the supplied load to actual load, the MPPT's are dialed back by a known amount, which can be calculated and displayed as potential power, and used for AUX port control too. 🤔

 

"Why SunSynk and Deye don't upgrade the firmware controlling the MPPT's to provide the potential / available solar is strange?" I don't think there is any way to determine how much solar power is potentially available without temporarily putting a load that's greater than the PV maximum on the MPPT's. You would have to do that every few seconds since the available PV power can change very quickly on a cloudy day or if anything throws a quick shadow over the panels.

13 hours ago, gthorn said:

"Why SunSynk and Deye don't upgrade the firmware controlling the MPPT's to provide the potential / available solar is strange?" I don't think there is any way to determine how much solar power is potentially available without temporarily putting a load that's greater than the PV maximum on the MPPT's. You would have to do that every few seconds since the available PV power can change very quickly on a cloudy day or if anything throws a quick shadow over the panels.

The MPPT's have a max and min capacity, and "know" the incoming Voltage and Current, and adjust the Resistance to maintain the required load Power on the output. Therefor by using the inserted Resistance (throttling the output Power) value, the Potential instant power could be shown. If a cloud passes by this will affect the output as expected.

10 hours ago, TimCam said:

The MPPT's have a max and min capacity, and "know" the incoming Voltage and Current, and adjust the Resistance to maintain the required load Power on the output. Therefor by using the inserted Resistance (throttling the output Power) value, the Potential instant power could be shown. If a cloud passes by this will affect the output as expected.

This makes sense - if it's dynamically adjusting resistance to match load then it has to know the maximum potential output power at minimum resistance.

Would be really nice if they'd expose this to the app/web as a way of measuring wasted PV on the charts!

It'd also be useful if Sunsynk/Deye replaced the existing Aux 'Solar Power' watt setting (which specifies in-use-solar - not all that useful if load is low), with 'Potential Power' instead (which would be what's available if there were sufficient load to consume it); so that the Aux port relay could be triggered only if the target desired PV is available. Right now it's only really useful as an indicator of the presence of PV rather than how much of it is actually available to consume.

Link to some more recent Aux adventures that cover some of the more confusing elements of using the Aux port; this thread helped me: https://powerforum.co.za/topic/11538-sunsynk-8k-aux-load-output-my-experience/

 

Edited August 28, 20231 yr by JayMardern

I first interpreted Power as the amount of “excess” solar power but then realized this doesn’t work if you’re zero export or off grid. The inverter doesn’t “know” how much power it isn’t generating, only the power it IS generating, so the engineers who designed these inverters kind of had their hands tied and came up with the best solution available. I’ll set this to something below my base load, like 100w or something, so that it’s “on” any time there’s solar. The smart load doesn’t know “how much” extra solar is available, only that it’s more than x.

the Sunsynk videos drive me utterly insane. They’re supposed to know how these things work and yet there’s absolutely some wrong information in their videos. The Power setting isn’t a limiter, it’s a trigger. Smart Load isn’t limited to battery power. It doesn’t NOT use solar power. If their inverter actually works the way they describe then I’d want nothing to do with it because their engineers are complete idiots. For example, I set Power to 500 watts, the port comes on, and it powers some device that requires more than 500 watts. This would be A Bad Thing. Priority #1 of a device that’s controlling potentially all of your loads, as mine is, is to power the loads. Full stop. Not providing enough power just isn’t an option so long as you’re grid tied. If that setting on the Sunsynk really is a limiter, then that’s A Big Problem and why the hell did they change it from the way the Deye and Sol-Ark work?