Multiplus low voltage alarm

DIY
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1

Hi guys,

I keep getting low voltage alarms, all below 12.30v but i cannot find where it triggers.

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Could someone point me to where this could be triggered?
Thanks!

2

Do you use ESS

3

Hi Fred, no I do not..

4

It is in the low pre alarm that you have shown there.

Its possible the terminal voltage is dropping that low.

If they are not related to a load switching on it might be good to check the battery temrinals and DC connections.

5

The low pre-alarm is at 11.80, it never drops that low.. lowest every night is 12.15 during loads.

6

At the battery terminals or at the inverter terminals?
The alarm comes from the inverter terminals.

If they are annoying and you feel they are spurious, you can disable the warning using the GX

7

Good point, I’ll disable dvcc and check again tonight.

8

So the multiplus sees a little different voltages but still not near what is set in the multiplus.

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9

I will say one thing about the vrm, 60seconds apart logging is sometimes not close enough to catch the actual event.

It is very likely it is going under that, the inverter will notice, the logging mat miss it.

11.8 is very close to 12.1 it is a 0.3v difference. You can also see the graph is slightly lower than where your cursor its and when when the warning logged as it logged shortly after the event.

Your system is hitting the warning level under load there. If it is annoying switch it off in the GX. It is only a short duration warning at the end of the day so a bit of voltage collapse under load.

10

Ok, with 41ah used overnight on 210ah batteries it’s time for some new ones then​:smiley:

Strange thing: I tried turning the alarms off in my venusos 3.80~14 but it is already disabled:

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11

Oh gosh. I was wondering. Thinking the voltage drop was huge for ~20A draw.

Interesting note on the beta…

12

Yeah it’s only the fridge that is on at the moment and it can’t even handle 8hours without some sun​:rofl:

13

Hi all, still not satisfied with it. I measured one of the first moments it made alarm and i see voltage around 12.20-12.23 when the multiplus thinks it is 12.22 at the lowest.
The exact moment i get an alarm it dropped below 12.30. So it must be the Multiplus is set to 12.30 (at one point it has been this year) but i just pulled the config and am sure it is set to 11.80.
I feel like this is a bug of some sorts in the Multiplus..

14

The recorded value may not be catching the full drop voltage or vrm is smoothing it out.
Did you look deeper in the csv data?
It is likely you could catch it with a meter. It may just be afor a split second. The inverter is noticing something.