Infini 3KW plus solar inverter settings query


#1

I recently installed a solar setup consisting of 12 Jinko panels of 320watt each along with Infini 3KW plus inverter and four Hyundai 150AH dry batteries.

I plan to make two string each with 6 panels. Total DC input voltage is around 278V. The short circuit current of each string is 9.05A Infini’s MPPT charge controller is rated at 18amp. So if I were to combine two strings with a short circuit current of 9.05 each, the total current would go up to 18.1A. Currently only 1 string of 6 panels is running. I plan to add the second string in the next few days.

Q1: Is it ok to combine two strings like this for a total current of 18.1A?
Q2: What are the ideal settings for Infini? My current settings are as follows:

Grid tie with backup mode 2
Charging source PV and grid
Load supply source (PV is available): PV, battery, grid
Load supply source (PV is unavailable): Grid, battery
Feed in to grid is disabled

Q3: What is ‘Max feed-in grid power’ setting? Currently it is set at 3000W and if I try to change it, it says I need the factory password? What is the ideal setting for this and what is the factory password?
Q4: I only want to discharge batteries by 30% what cut-off voltage should I set?
Q5: What is '‘Feeding grid power calibration’ setting for?
Q6: I enabled ‘Wide AC input range’, since I was having issues with an unstable grid frequency. Should I keep it that way?
Q7: I noticed Infini is using about 1A even though I have more than sufficient PV power. Is this normal? Is there a way to stop it from using grid power?
Q8: I got this black AC filter type box along with the inverter. Instructions with the filter box say that it should be used it if I have an unstable grid. I get fairly stable voltage in my area, but sometimes grid frequency fluctuates between 49.5 to 51.5. So I connected the filter box to the inverter and then gave it grid input. But that didn’t do anything to stabilize the grid frequency. What is the filter box for, because it doesn’t seem to do anything. Is it a surge suppressor of some sort?

I know its a lot of questions, but this is my first time getting into solar and I would appreciate if someone can share their settings for Infini 3KW plus. Thanks.


#2

(following reply is based on knowledge and data-sheets of respective components and is not a guarantee)
for Jinko JKM-320-72 Mono,
STC Voc, 46.4V x 6(panel in series) = 278.4V (should be less than 500V for infini 3kW+)
NOCT Vmp, 35.9V x 6(panel in series) = 215.4V
Infini Plus 3kW MPP-V-range is 250~450V and nominal of 360V.
Voltage wise, your system should work. but might not work at full efficiency.

Q1. combining 2 or more strings in parallel is ok. preferably with same panel-ratings, same angle and same direction. (when exceeding 2 strings in parallel, each string must be fused.) Infini should accept 18A input, while the 2-strings in parallel shouldn’t exceed 17.96A at STC Isc.

Q2. try to set such that the battery is used as last option. using utility(wapda/kesc) is cheaper than batteries.
preference should be PV, Grid and then battery.
check the type of battery set in infini and select based on type of batteries you are using.

Q3. when feed-in is enable, this will limit the amount of power infini can feed to grid. no idea about password.

Q4. (do not cycle batteries just to save from utility, batteries energy cost more than utility) voltage of batteries depend on amount of load they have on them, the type of chemistry they are, their age and more. 10.8V is considered as low cut-off volt for 12v battery of almost every lead based kind, with a reasonable current draw. I suppose somewhere around 12V would be close to 30% discharge, not sure though.

Q5. I suppose, calibration for internal current sensor of feed-in current.

Q6. consult manual of infini to check at which frequency range it is happy to operate in.

Q7. hybrid inverters do this to avoid any accidental feed-in to grid(when feed-in is disabled). they will keep a small load on line/utility side.

Q8. 49.5 to 51.5 Hz is ok. that black brick is most probably ac-line filter hopefully with surge protector. keep using it. wont do much for frequency though.


#3

Thanks for the info. System is up and running fine. But I am encountering one issue. Whenever grid goes down, AC output drops to around 8% load. So if load was 50% when grid was available, when grid goes down, only about 10% load keeps running despite the fact that enough PV is available and batteries are also close to 100% charged. As soon as grid comes back, all the loads that were disconnected are now re-powered through PV.

Do you know why this is happening?


#4

when you say “disconnected loads” or “output drops”, are some of the appliances connected to infini’s output turning Off, while some stays On? highly impossible, given that infini has single output.

or you are referring to the % value as shown on screen of infini?
if you are talking about screen values, maybe there is a glitch in software.

some more details of your load and more precise values might help in deciphering the root problem.


#5

double check, if feed-in is disabled.
do try to connect a pc/laptop with infini;
infini has a reasonable software to view current scenario and do settings comfortably.


#6

Yes that is exactly what I am saying. Some appliances are turning off while others remain on. It also seems impossible to me because Infini has single output. When this happens load % suddenly drops from 50 to less than 10%. Some lights, fans keep working but bigger loads like refrigerator switch off.

Feed in to grid is disabled. It’s not a software issue because I also connected it with my computer and it is also showing the same behaviour. See the image below.


#7

Is the “Neutral” from output-side of Infini connected to your house “Neutral”?

(with fans and lights working but heavy-loads not working, I suspect a loose/unavailable Neutral)

Usually, the Input-Neutral and Output-Neutral of an inverter are connected together at a point along with the House-Neutral.


#8

Your devices which turn off when there is no grid available have one wire from infini output and one wire (neutral wire most probably) from wapda directly. So when the grid has a break down, the devices cannot run as the electric circuit is not complete anymore.


#9

Inverter input has separate live and neutral coming from distribution box. Similarly inverter output live and neutral wires go back to distribution box.

I have two kinds of loads. Previously all the loads that were on UPS are now connected to solar inverter. These loads have separate live and neutral wire coming directly from distribution box. When the power goes out, most (but not all) of these loads keep working normally.

The second kind of load is the new load that I have placed on the solar inverter including fridges, TV, additional lights and a 1 ton AC. All these loads turn off when power goes. The live wires of these loads is connected to the inverter output at the distribution box. However, the neutral wires of these loads are not isolated The neutral wire coming from inverter output is connected to neutral busbar in main distribution panel to complete the circuit. I am not sure if this is the problem because usually this is the way Infini is connected to load normally.


#10

I would highly suggest not to use a common neutral wire or mixing of output of infini neutral with wapda neutral on the bus bar in your distribution box. If in any case, you change your electricity meter or you have to remove the wires from the meter and plug them back again, you run the risk of the current neutral wire going into the phase socket. Infini will shutdown if it finds that there is a grid phase coming in through neutral wire of its output, and that will be the best case scenario, it happened with system of my cousin. The worst case scenario will be that something will burn on the output of the inverter.


#11

How is your experience with Jinko panels by the way? I have been recommended this company by two sellers but I think a consumer can give more honest opinion than a seller as there is no conflict of interest.


#12

Well. I consulted about this matter with some installers and all of them connect the Infini this way. Since usually load live wires are isolated but neutrals remain on the main neutral bus bar and they bond inverter neutral with main neutral on distribution panel. But you are right that isolating neutrals is better. I could try and isolate them, it will take me some time, but I can get it done. But I don’t think I have a wiring issue as such, I am thinking there is some issue with the inverter.

So far Jinko is good. I have the JKM320-PP-72 model. But as with any solar panel can’t say how it will perform in the long term. But Jinko panels are A grade and should last a very long time.


#13

If it was an inverter issue, it would not supply power to any load. It has to be the wiring issue.

Thanks for sharing your experience with your panels. I am very satisfied with my Solarworld panels however getting the same wattage panels of the same brand seems improbable to me.


#14

Do you know about pvoutput.org website for solar data logging and sharing?


#15

Yes. I do know about it. There is also emoncms. Solar power software that is available with Infini cannot upload data so you can’t really use it with pvoutput or emoncms.There is a software called ICC (Inverter Control Centre) that can work with Voltronic inverters and also upload data to pvoutput as well as emoncms. ICC comes with a 7 day trial after which you have to purchase it. I have used ICC in trial mode. Its much better than Solar power software, but I didn’t get time to set it up with pvoutput because the trial period expired. You can download it from here


#16

I have the paid version of ICC for a while now. The links of Emoncms and Pvoutput.org of my system are:

https://emoncms.org/dashboard/view&id=50400

https://pvoutput.org/intraday.jsp?id=61384&sid=54649


#17

I have free version of ICC but it only works with Axpert inverters. If you want it, let me know I will share it with you.


#18

Are you using windows or pi version? How much did you pay for it?


#19

I have the windows version. I paid 80 dollars for it, I was trying my best to work with the free version at first but it caused few problems for me, others are using it with no problem though. There is a guy who is using dual tracker solar system in Pakistan, he suggested me to go for the paid version as the support from the software manufacturer is really great.


#20

I used the free version of ICC for a few days, didn’t get a chance to explore it completely. Does it have an event log/fault log like Solar Power Software does? I didn’t find one.