Cable length from battery to unit is 1.2m (cable is 25mm2)
No solar
No greed feed in
Servo Voltage stabilizer before MP2
ESS setup:
My idea was to charge battery during night hours and use battery power during the day. So setup is next:
Scheduled charge from 23:30 till 07:00
Grid setpoint 50 (tried different values in range 0-300, no impact on the issue)
Mode - optimized with battery life (also tried without battery life)
DVCC:
Max charge current - 20A
Maximum charge voltage - 52v
SVS, STS, SCS - off
Average load is 50-2000w.
I noticed that sometimes when AC is on and inverter is on I hear strange recurring noises. For some reason I see that battery is charging during the day (but I have scheduled charge set in ESS). From time to time I see Inverter Overload warnings.
Voltage stabilizer has no impact on system behavior. I tested with stabilization and bypass modes - no difference.
Important note: If I turn off AC the issue disappear and inverter works quietly without any issues.
Hello.
Yeah, I know that battery is not enough. I am in a process of adding more. As I mentioned, the load is not more than 2000w, so this battery is enough for now. Battery cable size is the same as original pylontech cable that came with battery.
Also, when ess charge schedule is active in the night, there are no problems and strange sounds. The temp of battery is 27 degrees even during charging.
Hello
TBH I don’t know the bypass mechanism in my stabilizer. I physycally removed it from the chain for the test today and result is the same → When ess schedule ends at 7am, I see that inverter tries to charge battery and that weird noise appears again.
The 8KVA MP-II and up units tend to have much louder harmonic / resonance than the 5KVA and smaller units. I personally prefer to install 2x5KVA units over a single 8 or 10KVA.
Can you confirm the following:
the resonance sounds like the inverter ramping up every few minutes only for a second or two?
(for me this seems to have been resolved by replacing the ET112 Grid meter)
overload warnings occur ONLY WHEN CONNECTED to the grid and with ESS enabled?
What lenght and size is your main supply cable?
As for the batteries in your system being too small, that is true as the UP5000 (4.8KW) is only a C0.5 unit meaning max load is 2.4KW. But I don’t think your overload warning is due to that, infact I personally have never seen a Victron or any other low frequency inverter give an overload warning due to a too small lithium battery (the battery’s BMS will disconnect or in some lower quality units’ case damaged before that). In which case the error would normally be “low battery voltage” sometimes also “High DC Ripple”.
1 yes. The sound is recurring. That sound on the video I posted could happen for hour without stop. I have no external grid meter, so nothing to replace as of now (I hope:)).
2. Yes, happens only with ESS enabled and in period of time when battery should NOT be charged. Check screen record attached here. My schedule is to charge starting 23:30 till 07:00 (soc 100%) and from 07:00 till 23:30 soc 25% (as I understand from description, it should wait 16+ hours or soc to become less than 25% without charging).
3. Main cable is 4-5 meters long, not more.
Also, I am sure it is not related to battery and its wiring. Because when AC is physycally off I have no issues.
The most strange part on video is the fact that it tries to throw something back to grid (send to grid is disabled in settings) and attempts to charge battery in wrong period of time. Maybe it sound stupid, but it looks like bms tries to override settings of cerbo/victron.
edit I just heard the audio in the original video. This is typical of an 8KVA or higher unit especially the first models (roughly 2 years or older). They were noisy as hell. I have one, where the whole internal PCB was replaced (latest Hardware), running in our worksop at the office and it still does this with an 80W soldering iron and/or an 800W reflow station. Although it is quiter with the new pcb than it was with the original pcb. No matter that the overall load is under 1KW.
The Grid side will never be “0W” it will only be close to… If you don’t want anything at all pushing back to grid then try changing “GRID SETPONT” a litlle higher eg. 150W (settings>system setup>ess). Unless it was changed to “0W” then change it back to “50W” and see if it improves.
Normally the std 50W setting is sufficient, If you change it to “0” for instance it tends to do what it shows in your video (+ or - 0).
Unfortunatley the audio seems to be muted, I can’t unmute it. But from your description it sounds typically like an 8KVA, they are noisy unfortunately.
With grid supply cable lenght I actually meant from the supply pole / council meter.
“Maybe someone from victron could bring some light on thia issue?”
not be that guy, but that will not happen on this forum unfortunately.
If you could post your settings from your cerbo, maybe someone would be able to assist.
My honest opinion:
If it is that noisy at 0 load, take it back to your supplier. It may or may not resolve your issue but at least it will be quiter (if they replace the PCB)
I don’t care about noise bc inverter is in my boiler room, so i don’t hear it. I care only about behavior when it tries to charge battery when it ahould not.
Attaching my cerbo conf and veconfig also
Also, I bought my victron from nkon and if I want to send it for revision/replacement I need to pay another 200-400 euros in best case scenario, that’s why I decided to check all here on forum before calling shop support)
Maybe I don’t understand correctly or I’m just being stupid.
From the last video, I don’t see the battery charging? Yes there is a slight charge/discharge of +/- about 40W in your video (remember the inverter is powered from battery and not grid). But that is not an issue, it is such a small amount and is basically down to calculation. I see these minor variations on all my sites all the time, these values are not exactly “spot-on” but rather an average (give or take)
Unless of course there is a charge of close to 20A (as set in DVCC) which is not shown in the video.
Unless there’s something at fault with the MP-II I would think these issues are unrelated (Overload warning, Charge Schedule, Resonating Noise. If I understand your post correctly)
Yes, I am talking about those short charge/discharge jumps. That noise what I am talking about happens exactly in moment when that charge/discharge happens
