October 9, 20196 yr Hi, My system has been acting strange since yesterday, ESS is using much more than my grid setpoint, while my battery is 100% charged and throttling my East String. No errors or anything, I have also restarted the Venus with no luck. Any ideas? The only difference with this MPPT is that it is connected via USB to the Venus. Was fine up untill 11:19, then just dropped again. Yesterday similar behaviour at around 12.
October 9, 20196 yr Author The other thing that I have noticed is that the SVS/STS settings are not aligned to what is recommended, not sure if this was always set like this since the install. Anywhere to perhaps check change logs on my device to see if anybody perhaps tweaked it? I know my installer does show clients my system, but not sure if they might of turned it on?
October 9, 20196 yr 51 minutes ago, PaBz0r said: 11:19, then just dropped again One of two things i can think of. Please check if both the screws on this little wire on that MPPT is tight. Please make sure you did not limit the inveter output to 2000-2500watts?
October 9, 20196 yr Have you configured a maximum power output for the Inverter? If the inverter is limited to, say 2000W, then any additional load will be sourced from the Grid. [Edit: Jaco beat me to it 🙂 ] Edited October 9, 20196 yr by NigelL
October 9, 20196 yr Author Hi, Jaco will have a look it seems, but from my memory I have not set any limit, it was running the oven and geyser on Sunday without hiccups. Noticed this behaviour yesterday for the first time. I normally check when the Geyser runs and that everything is fine at home and picked this up.
October 9, 20196 yr 1 hour ago, PaBz0r said: Noticed this behaviour yesterday for the first time. Please let me know if it happens again, i would like to check a few things while its happening?
October 9, 20196 yr Author I just want to thank @Jaco de Jongh for looking into it for me, it really just shows how great this forum is. Will keep you posted if it happens again. What he changed was the sustain voltage, it was over 50v, back to 48. Additionally changed the grid code to NRS (ps. I see that the Multiplus II 48/5000 is also now NRS certified asof August, coming to an approved inverter list soon I guess, attached is the certificate), additionally he cleaned up all my unused sensors. I will check the MPPT for loose connections tonight, hopefully this is now sorted. Certificate-NRS-097-2-1-MultiPlus-II-48-3000-35-32,-48-5000-70-50-and-MultiPlus-II-48-3000-35-32-GX.pdf
October 9, 20196 yr Author Ok so.. it seems that it is derating itself as I can now see VE Bus Warnings for the periods it was using grid:
October 10, 20196 yr Hi PaBz0r I am not sure if this applies in your case, but there have been some reports on the Victron forums about a batch of the new Multiplus-II 5k units giving over-temperature alarms and then failing after a few weeks. These over-temp alarms have happened without any large loads or obvious reason.
October 10, 20196 yr 37 minutes ago, NigelL said: Hi PaBz0r I am not sure if this applies in your case, but there have been some reports on the Victron forums about a batch of the new Multiplus-II 5k units giving over-temperature alarms and then failing after a few weeks. These over-temp alarms have happened without any large loads or obvious reason. Could you post links to those reports please.
October 10, 20196 yr Author 1 hour ago, NigelL said: Hi PaBz0r I am not sure if this applies in your case, but there have been some reports on the Victron forums about a batch of the new Multiplus-II 5k units giving over-temperature alarms and then failing after a few weeks. These over-temp alarms have happened without any large loads or obvious reason. Hi Nigel, As Sean asked, would you please share links? My issue is my install is in a cupboard in the garage. The garage ambient temp is high, plus I have 3 X MPPTs and 2 X Pylons in there as well. I have put in an extractor fan, but this only helps to a degree due to the ambient temp. I am looking at other options to insulate the garage to help with the problem in the mean time.
October 10, 20196 yr 1 hour ago, PaBz0r said: Hi Nigel, As Sean asked, would you please share links? My issue is my install is in a cupboard in the garage. The garage ambient temp is high, plus I have 3 X MPPTs and 2 X Pylons in there as well. I have put in an extractor fan, but this only helps to a degree due to the ambient temp. I am looking at other options to insulate the garage to help with the problem in the mean time. Okay - that sounds more like a valid thermal limit rather than a symptom of a faulty unit. See the following links for reports that I mentioned in my previous post. https://community.victronenergy.com/questions/29805/multiplus-ii-5kva-showing-temperature-alarm-on-led.html and https://community.victronenergy.com/questions/29194/multiplus-ii-48500070-continuous-overload-shutdown.html?childToView=29248#comment-29248 [Edit] I also found a reference to a Victron Toolkit App that can calculate the temperature derating - i.e. how the max power output drops as the temperature increases. I have not tried this app. See https://www.victronenergy.com/blog/2014/10/02/victron-toolkit-a-new-app-for-android-and-iphone-users/ Edited October 10, 20196 yr by NigelL
October 10, 20196 yr Author Doing the same today, so I will need to make a plan. Looks like rain later this afternoon, so should cool down later on.
October 14, 20196 yr On 2019/10/09 at 4:22 PM, PaBz0r said: sustain voltage Aaah yes! I see that a lot. If the voltage pulls below the dynamic cut-off curve configured into the ESS assistant it goes into Sustain mode. It remains there until the battery voltage rises around 1.2V (or whatever you configured) above the sustain voltage. Now with a pylontech battery where you have either value set too high/low... this can lock you out of self-consumption mode for some hours. While in sustain mode it charges slowly from the grid (around 5 amps). At that current an LFP won't be showing a voltage rise for days. Even had one customer that had his sustain voltage set to 55V. And his PV was AC-tied (so the Multi does all the charging). It was permanently stuck in sustain as it could not get the voltage over 56.2V... 🙂
October 14, 20196 yr Author Still not convinced that it should be derating, the ambient in the cupboard was 22°C with a fan blowing on the inverter
October 14, 20196 yr Can you confirm that the internal fan in the Multiplus 2 is turning on when it is supplying a load as shown previously?
October 14, 20196 yr Author 5 minutes ago, NigelL said: Can you confirm that the internal fan in the Multiplus 2 is turning on when it is supplying a load as shown previously? Yes the fan does come on, even at night the fan is on with like a 400w load. Yesterday with the above load, it was the toaster and microwave that was on like at 9am, so not even heat of the day
October 14, 20196 yr I recommend contacting your supplier - a 5kVA Multiplus 2 should not be thermal-limiting at around 2000W when your ambient temperature is 22C. I have the smaller 3000VA Multi-2, and it has never once had an over-temperature alarm even when running at full power (2400W). The ambient temperature in the house has often been over 27C in summer.
October 14, 20196 yr My 3000VA Multi-2 derates itself from 2400W to 2000W after running the geyser for about 45 minutes every time. No temperature warning and ambient temperature 23C.
October 14, 20196 yr Author 53 minutes ago, NigelL said: I recommend contacting your supplier - a 5kVA Multiplus 2 should not be thermal-limiting at around 2000W when your ambient temperature is 22C. I have the smaller 3000VA Multi-2, and it has never once had an over-temperature alarm even when running at full power (2400W). The ambient temperature in the house has often been over 27C in summer. Yes it doesn't make sense to me either, it is way off the charts to limit at about 2000W that would be 50% basically. It should of shut down by then already according to the charts. @plonkster any thoughts? Not sure if it is thinking it is a 3000kva multi
October 14, 20196 yr Author Already derated itself when the geyser kicked at 10:42 : Edited October 14, 20196 yr by PaBz0r
October 14, 20196 yr 3 hours ago, PaBz0r said: any thoughts? Not sure if it is thinking it is a 3000kva multi Multi will derate itself to avoid overheating. Normally max power is 80% (when running grid-tied), that is 4000W. If it gets hot, it derates to 60% (3000W). I've never seen a Multi get so hot that it had to derate to 60%. Other things to check, make sure it's not the battery or something else dialing it back by limiting the discharge current or something similar.
October 14, 20196 yr Author 2 hours ago, plonkster said: Multi will derate itself to avoid overheating. Normally max power is 80% (when running grid-tied), that is 4000W. If it gets hot, it derates to 60% (3000W). I've never seen a Multi get so hot that it had to derate to 60%. Other things to check, make sure it's not the battery or something else dialing it back by limiting the discharge current or something similar. Yeah it doesn't seem to be normal. Today it would derate then 5 minutes later be back to normal, then derate again. Ambient today was around 26°C. I have now even installed insulation in the garage... lets see what tomorrow holds, the installer will speak to Victron tomorrow to see what we can do. Edited October 14, 20196 yr by PaBz0r
Join the conversation
You can post now and register later. If you have an account, sign in now to post with your account.