EG4 18kPV Q+A general thread

[Luxpower_Gilbert]

Yup, this makes sense for on-grid and I have no worries about it. I want to understand your guarantees for off-grid better.

The inverter is pretty fast to de-energized the gen port when i did my test.

The worry is if you max out the 16kW AC coupled, and it's outputting at 100% to satisfy 4kW of loads and 12kW of AC charger. If the loads turn off then there is risk of overvoltage damage until the FreqWatt or relay can react quickly enough. Or the AC charger has surge charging capacity to compensate and sink the current.

You have to sized your system correctly. If your not planning to sells to the grid then I recommend more storage. If you use more power during the day then more pv.

This also depends on the BMS capabilities on the connected battery, for instance the PowerPro defaults to 100A charge, 200A discharge on a single battery. Now given the PowerPro surge spec I think AC coupling in 10-12kW on a single battery should be safe since I would be surprised if F-W response is too slow. This also does not require me to know the LuxPro AC charger's surge rating, since the continuous rating is enough to satisfy this.

Inverter max charge output is 250A. Like i said sized your system correctly.

 

[zanydroid]

Are we talking about the time on the inverter? Mine pretty accurate, i set the time advance on the seconds digit, while looking on my phone with the clock app i the will try to press the set button when my settings on the inverter match on my phone clock.

Quattrohead is asking about AC frequency stability. He has appliances that rely on frequency to keep time. Based on his reported drift of 5min / week, that means the Inverter output frequency is off by average of roughly .05%

 

[Luxpower_Gilbert]

Quattrohead is asking about AC frequency stability. He has appliances that rely on frequency to keep time. Based on his reported drift of 5min / week, that means the Inverter output frequency is off by average of roughly .05%

On grid w/grid assist. Mine is pretty stable.

 

[zanydroid]

On grid w/grid assist. Mine is pretty stable.

Yes, that is expected because grid assist synchronizes frequency with grid. And grid frequency in many parts of the world are corrected from time to time to force clocks back to sync.

I assume Quattrohead is running off grid. If off grid the inverter is the only thing responsible for keeping a stable frequency.

You probably also have to add up and average the data over a long period of time. With 2 decimal points that data can resolve down to .016% of 60hz, which is enough to detect the .05% drift that I calculated for the frequency drift the other user is seeing.

 

[Luxpower_Gilbert]

Yes, that is expected because grid assist synchronizes frequency with grid. And grid frequency in many parts of the world are corrected from time to time to force clocks back to sync.

I assume Quattrohead is running off grid. If off grid the inverter is the only thing responsible for keeping a stable frequency.

You probably also have to add up and average the data over a long period of time. With 2 decimal points that data can resolve down to .016% of 60hz, which is enough to detect the .05% drift that I calculated for the frequency drift the other user is seeing.

This most likely expected with off grid applications, if the load is not stable. High surge load will affect sometimes the frequency.

 

[Zapper77]

Stove, microwave and the all important to Mrs QH coffee pot ?

Which firmware version are you using?

 

[Quattrohead]

I am totally off grid.
Time on the inverter is always correct.
Clocks on stove, microwave and coffee pot all drift by the same amount, around 5 mins slow per week.
Firmware is 1312.

 

[Quattrohead]

This most likely expected with off grid applications, if the load is not stable. High surge load will affect sometimes the frequency.

If that is indeed the case, this is poor design and not acceptable.

 

[Zapper77]

If that is indeed the case, this is poor design and not acceptable.

Sent you a PM.

 

[Shimmy]

This most likely expected with off grid applications, if the load is not stable. High surge load will affect sometimes the frequency.

To the original point, on a hourly basis if the inverter has not had exactly 216,000 cycles it needs to speed up or slow down the frequency for a short period of time to compensate.

 

[Shimmy]

For the dryer. I use eco mode setting on my dryer. Takes a little over 3 hours to dry the clothes but the peak wattage draw drops from 6,000 all the way to 2,000 and usually save 0.5-1kWh

I finally got my wife to try on our dryer; metering attached. The second load was on low heat. Dramatically lower energy, but peak power was the same. I was initially concerned that maybe it was switching the heating element to 120V and my metering was off, but looks like it just modulates to a lower temperature.

 

[Luxpower_Gilbert]

If that is indeed the case, this is poor design and not acceptable.

I’ll try to look on your data and share with other LuxPower Technical Support.

 

[Zapper77]

I finally got my wife to try on our dryer; metering attached. The second load was on low heat. Dramatically lower energy, but peak power was the same. I was initially concerned that maybe it was switching the heating element to 120V and my metering was off, but looks like it just modulates to a lower temperature.
View attachment 167847

How about a eco mode?

 

[Markus_EG4]

I am totally off grid.
Time on the inverter is always correct.
Clocks on stove, microwave and coffee pot all drift by the same amount, around 5 mins slow per week.
Firmware is 1312.

The clock should have their own Crystal oscillator to keep the time on track. Most appliances have them cheaper ones don’t.

 

[Shimmy]

How about a eco mode?

Mine doesn't have a real eco-mode unfortunately.

 

[ajalger]

Probably a dumb question but I'm stuck. Yesterday had a battery status check error. Looked at the 6 batteries and one was in alarm but others were all charged. Restarted the problem battery and the alarm cleared but then now the inverter isn't backfeeding any power. The CTs are still working. The batteries are basically 100% and occasionally it uses a little solar to top them off but nothing being back fed. The main panel breakers are on, I've restarted the inverter with the menu option as well ad doing a full shut down (solar/battery/grid) and no change. Tried changing some settings so maybe now I've loused something up but there just isn't much to see. Could anyone point me in the right direction? Is there a hidden option to reset all of the settings as well to start fresh?

 

[pvgirl]

Does the 18kpv have a revenue grade meter for measuring PV production for SRECs, or other production based credits? If not any hope for adding one in a future hardware revision?

 

[Markus_EG4]

Probably a dumb question but I'm stuck. Yesterday had a battery status check error. Looked at the 6 batteries and one was in alarm but others were all charged. Restarted the problem battery and the alarm cleared but then now the inverter isn't backfeeding any power. The CTs are still working. The batteries are basically 100% and occasionally it uses a little solar to top them off but nothing being back fed. The main panel breakers are on, I've restarted the inverter with the menu option as well ad doing a full shut down (solar/battery/grid) and no change. Tried changing some settings so maybe now I've loused something up but there just isn't much to see. Could anyone point me in the right direction? Is there a hidden option to reset all of the settings as well to start fresh?

View attachment 168158

You have charge last selected this takes you out of self consumption mode

 

[ajalger]

You have charge last selected this takes you out of self consumption mode

I changed that and didn't see a difference. I restarted the inverter through the menus too

 

[y0bailey]

I'm planning to add some panels to my AC coupled 18kpv (waiting for delivery) and I have a couple of questions regarding the MPPT inputs and adding panels to the PV inputs.

I'll be adding 8 south facing ground mount panels, and I am leaning towards running 4s2p because I will get some AM/PM shading as the sun moves over trees to hit the panels. They will be in the same area, and all the same panels facing the same direction.. But the shading will move across both mounts slowly and can take an hour or so to clear.

I worry about the ~155v that a string of 4 is too close to the lower end of the MPPT rating during those shading hours...Should I?

Also, should I worry less if both of these strings go into the MPPT 1 port and are paralleled at the inverter? I don't know enough to know if that will help me stay inside the MPPT range or not?

I can easily put these in 8s and will keep that as a backup plan... But if I shouldn't waste my time experimenting with parallel to try to help my shading situation when I'm that close to the lower end of the MPPT range I would like to know ahead of time!

Thanks!