question

spicedreams avatar image

Many overload warnings- do they matter? How can I tell?

I have an EasySolar II GX which includes a MultiPlus ll 48/3000/35-32 inverter/charger, and 8x 260 Ah AGM batteries (2p4s for 48 V nominal). I am completely off grid.

I get many (4-8 per day) "Overload L1: Warning" messages from VRM. They are cleared after ~20 seconds. I have firmware v2.66 on the GX device and v481 on the Multiplus (supposed to cure spurious Overload warnings).

I have tried to find out what causes the overloads. There is a small AC freezer (90 W nominal) and a couple of water pumps and a water heater BUT the overloads are not always attributable to these- they happen sometimes when water heating is off, no-one is triggering a pump and the freezer is not starting. They also happen sometimes when the freezer starts working.

So my 'need to know' question is- are these repeated overloads causing any harm? Are they shortening the life of my system? Can VRM tell me any more about them?

Thanks,

Graham

MultiPlus Quattro Inverter ChargerMultiplus-IIEasySolar All-in-One
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@warwick, @Daniël Boekel (Victron Energy Staff), @Guy Stewart (Victron Community Manager)

Here is an overload captured in VRM graphs. At 09:49 local time, AC output current FELL from ~2.5 A back to "base load" of ~1 A. This corresponded with (caused?) a spike in AC output voltage from its normal 229 V to 237.5 V.

screenshot-at-2021-06-05-10-11-08.png

And both these corresponded with (caused?) an Overload warning.

Overload L1: Warning

This email is generated by Automatic Alarm Monitoring on the VRM Portal. More information:
https://www.victronenergy.com/live/vrm_portal:alarms#automatic_alarm_monitoring

https://vrm.victronenergy.com/installation/91866/dashboard
Site time: 2021-06-05 09:48:13 Pacific/Auckland

There was a similar event at 09:09 local, again looks like triggered by a (larger) fall in AC output current, but VRM did not capture such a pronounced spike in AC voltage.

screenshot-at-2021-06-05-10-22-08.png

Is there any more information needed to debug this?

sorry, this is a repeat of the previous comment which as far as my browser could tell me, had been lost. I will leave it here 'in case'.

@Guy Stewart (Victron Community Manager), @Daniël Boekel (Victron Energy Staff), @warwick

I have got some good information out of VRM corresponding to the Overload warnings.

screenshot-at-2021-06-05-10-11-08-overload-0949.png

This seems really clear. at 09:49 there is a drop in AC demand, and a corresponding surge in AC output voltage to 237.5 V (from the normally very stable 229 V) and then an email Overload Warning. I can supply a .xls output from VRM covering this period, though this software will not let me upload it.


screenshot-at-2021-06-05-10-22-08-overload-0909.png

09:09 there was a slightly less clear episode but again, it looks like a drop in demand led to an increase in AC voltage to 230.9 V, and subsequently an email Overload Warning.

In both cases, AC demand grew relatively slowly, and the Overload Warning was triggered at the point where the demand switched off. In neither case is there any AC load coming anywhere near the 3 kVA advertised capacity of the EasySolar system.

Just for clarity, there is no DC load or AC input. Just solar input to batteries and AC output.

So, why am I getting these warnings? Is there something I need to fix?

Well, the Overload warnings stopped 2 days ago.

Warnings stopping seems to coincide with me uploading a slightly changed MultiPlus configuration via VRM Remote Configuration. I attach the "before" (20210606) and "after" (20210607) versions of the settings dumped out of VE Configure locally.

after VEConfig+20210607+exported-settings.TXT

before VEConfig+20210606+exported-settings.TXT

What is new in the 20210607 version?

On the General tab, settings for a VE.Bus Battery monitor have been added (even though I actually have a BMV 700 connected by VE.Direct, which should take precedence?). But these settings were also there in the 10-days earlier version, which still got as many Overload warnings as the 20210606 version, so probably not directly involved.

On the Inverter tab, the 20210607 version added State of Charge shutdown (50%) and restart (60%), and reduced DC shutdown voltages from 48.2 V to 47.24 V (and a similar shift for restart). This change was made because with the 20210606 settings, starting a small microwave caused the battery voltage to drop below the 48.2 V threshold shutting the Inverter down (it had been bad weather and the batteries were already low). I hoped that using SoC instead should make it tolerate such small draws better? But it requires the VE.Bus Battery monitor settings on General.

No changes on any other tab. I hope most of this was more or less factory default, since I only just found how to adjust it and I don't believe the installer did much either.

Once more @warwick, @Paul B, @Guy Stewart (Victron Community Manager) thanks for looking into it, I would really like to understand what is going on here.

@Paul B , @Guy Stewart (Victron Community Manager)

Spoke too soon, overloads are back. 4 Overload Warnings out of the blue, at 10:45, 10:48, 10:51 & 10:54 in the attached log of just the relevant hour at 1 minute intervals:

0281b4e27a85_20210613-1041_to_20210613-1141-4-warnings-after several-days-no-warnings.xls.zip

Possible user involvement; turning on a printer (but not actually printing; that was later and caused no warnings) and using a 700 W microwave oven for 1 minute. I can't be sure if either user event corresponds with a warning.

2 Answers
Warwick Bruce Chapman avatar image
Warwick Bruce Chapman answered ·

Are you feeding into the grid? If yes and your PV array is bigger than the inverter, then your inverter will be working near max to export as much as possible and generate warnings before being backed off a little.

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Thanks @warwick. No, we are 100% off grid: nothing in or out.

Is it getting hot? What is the baseload? Would you be willing to let me look at your VRM?

spicedreams avatar image spicedreams Warwick Bruce Chapman ·

Thanks @warwick

Not getting hot. Baseload is 150-250 W, including ~35 W the EasySolar self-consumes.

I am happy to let you see the system- I think (and trust Victron) this is readonly... https://vrm.victronenergy.com/installation/91866/share/90b1227a

How do I make this "not an answer"?

you use Reply to the question, if you post a Write a Answer then this makes it a answer

Thanks @Paul B, but of course the post I want to make 'not an Answer' was not mine... It's an attempt to help, but not an answer.

Paul B avatar image
Paul B answered ·

Hi one of your replys say you got a email so you may have setup emails to be sent to you when the ac voltage goes over a set figure

if this is the case this is not a inverter overload,

the below VE.Bus warnings and alarms can show you it and I have not seen this in any of your screen shots ?????

1622958499135.png


1622958499135.png (30.0 KiB)
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Thanks @Paul B.

I do not have emails sent when AC voltage changes. I have the (default?) Automatic Alarm Monitoring set to Warnings and Alarms, and that is what sends me the Overload warnings.

I don't have any AC input, so no point in the second graph you show. But here is the VE.Bus Warnings and Alarms graph for the period covering the two Overload warnings I reported above:

screenshot-at-2021-06-07-15-06-51.png

It confirms there were brief VE.Bus Overload warnings at the times I reported. The 09:49 Overload corresponds with an AC voltage spike but the 09:09 does not. There is a much larger AC Amps spike at 09:52 which results in neither an AC Volts spike nor an Overload Warning.

@Guy Stewart (Victron Community Manager) the MultiPlus firmware 481 was intended to cure "spurious Overload warnings". What made those that it cured spurious? Could these affecting me still be spurious warnings?

Can I provide any more information? What else can I do to debug this? I am really anxious to get this out of my headspace.

There is not much more that can be done currently, Its also not affecting the operation so dont worry to much - would be my comment. put up with it and move on.

I have added more comments below

The overload warning is a calculation for inverter temp - AC amps and AC volts out and also battery DC voltage and DC amps in. as you are using AGMs and NOT LiFeP04 you maybe have a large DC volt drop here, there could even be a bad connection between the batteries or even a faulty battery, (I DONT KNOW) - and all these can add up to a spike of some kind, ie a example is 52v x 20amp is 1040VA or 42v x 24.76 =1040VA this also occurs on the AC side as well so you can see that as the volts drop the amps increase to hold the output VA.

AS a example only - at 25 deg C as temp rises then the max amps reduces

Now the inverter LOOKs at the AMPS mainly ( high amps cause heat and thus problems) and the units are restricted to MAX amps ie 3000VA /230 ac is max amps of 13 amps AC or DC is 3000/52v max amps is 57.69amps - so as a example if for some reason the amps go over 13AC or 57.69DC you will get a overload warning. The above is just a example and is not taking into account ANY losses or overhead etc,

I am not saying the above is 100% correct but its a indication of whats going on, some times its hard to get your head around it as well. but it may give you something to look for.

NOTE the VRM does not pickup all the data if you are set to 1 min updates then it takes a sample reading every 1 min . Therefore data between readings is MISSING. and this maybe the spikes you are looking for. ??????

to fix this you would need a onsite monitoring system that records all the voltages and input amps etc in a Milli sec to Milli sec basis.

therefore I cant give you a reason, and all we here at the community can do is try to help you to pin down the cause and to help all others that may also be having a concern.

Once a final DUPLICATE-ABLE cause can be found the I am sure victron would address it if its a issue with the fireware. Currently they have done there utmost to help in fw 481 but in your case its still showing a overload.

I would suggest that you ask your dealer who did the install and setup to have a look and see if there is some other item on site that can be pointed to, (onsite time is not a warranty item by victron)

if you did the install yourself then it really needs a physical check to make sure its done fully to spec.

I am just trying to help here and not point fingers at anyone.

TO help further we really need to be able to duplicate this.

I hope you see were we are coming from.




Thanks @Paul B. I am also not trying to point fingers,

Install was by a qualified solar engineer and a ticketed electrician who have both done many such installations (but I am guessing, not many actually off grid).

I am trying to find out why the overloads are being generated in my very low load situation, so I know if it needs fixing and perhaps how.

@Guy Stewart (Victron Community Manager) https://community.victronenergy.com/users/14/guy.html

Is there any way to get the Victron kit to log the data frequently enough to diagnose this further? I have a tiny linux box sitting right next to it and on the same lan that could store the records if need be.

Thanks, Graham