Hi everyone,  I'm new to the solar thing and have just acquired a Growatt 5kw invertor, 4.8kwh Ultra Energy battery and hooked up 3 panels (2×600w plus 1x540w). I'm happy with the system as it works fine during load shedding. But don't understand why the invertor shows that the PV is giving around 135v but generates between 1-6 watts energy during the day. The point of getting the panels was to charge battery in the event that cables are stolen so I can have power at night. But now this is not going to happen at 5watts. Is the power output normal for this number of panels? Or could there be an issue with the installation? Please help

The MPPT range is 120Vdc- 430Vdc
Startup voltage is 140Vdc plus or minus 10Vdc
Have you measured the Voltage from your Solar array with a multimeter to check what it actually is?
My suspicion is your Voltage is on the lower limits and as soon as you try and draw some Amps the Voltage drops below the lower limit.
You may need a 4th panel to solve your issue. 

Thanks zsde, I know the reading on the multi meter matched what the inverter read. I also noted on the app that at some points I get wattage spikes which then disappear after a few minutes/seconds and that baffles me. It makes me think there is an issue with the inverter. I take the point about possibly needing a 4th panel and will consider when spare cash is available. I just expected to see descent wattage being produced as I was told this would be enough to charge the battery. I have asked installer to come check and hopefully he figures out the cause. In the interim I hope no cables get stolen. 🤞

29 minutes ago, Unity said:

multi meter matched what the inverter read

What was that reading in Volts? 
Looking at the one solar spike in your graph indicates an erroneous reading. Your three panels add up to 1740W in lab conditions. So if that is your data, then the solar production graph is rubbish.
Look again at your three panels VOC and in series add that up. Then deduct 10 - 20% for real world conditions and that should be your expected Voltage. Assuming your panels are 50V, then under ideal conditions you can expect 150V ignoring any losses.
Does that voltage exceed your Inverter start up voltage ?  
I reiterate, as soon as your solar energy and voltage is sufficient, the Inverter will pull the max MPPT curve for those values and try and charge the batteries. As soon as the load increases your voltage drops, and that drop may just end up below the minimum required.
I have the same Inverter.
Here is my graphs for today. I have 6 panels in series meaning a lab condition max of 300V. On a good day I may see 270V
However note this mornings voltages and during the same time period, the amps and watts. 
150V at around 05:06
That brought me 2W
The first time I got above 10W was at 05:18 by which time the Voltage was fluctuating between 180 and 240V.
Yes, the early morning sun is still weak, so not much to be expected even at higher voltage. 


In the second set of graphs I try to show the voltage drop under load. This was from 12:00 to around 12:30
It starts with a baseload of around 500W.In the voltage graph after that you will see around 260V.
From about 12:10 there was a fairly constant 3000W load and you will see the Voltage drop down to sometimes 230V.
So I maintain that your panels may just not generate enough Voltage to get the MPPT to generate anything under load. But I stand to be corrected. 

 

Zsde, well put and I don't have any more doubts. This is what I love about this platform- unbiased feedback from user experience. I will make a plan to get the additional panels and look forward to a loadshedding free experience. Thanks again for your efforts 👌🏽 

11 hours ago, Unity said:

Thanks zsde, I know the reading on the multi meter matched what the inverter read. I also noted on the app that at some points I get wattage spikes which then disappear after a few minutes/seconds and that baffles me. It makes me think there is an issue with the inverter. I take the point about possibly needing a 4th panel and will consider when spare cash is available. I just expected to see descent wattage being produced as I was told this would be enough to charge the battery. I have asked installer to come check and hopefully he figures out the cause. In the interim I hope no cables get stolen. 🤞

With the 3 panels you have, let's assume they are rated at 50 V they will generate 150 V minus +_ 10 to 20 % that is very low to trigger the MPPT, you need to add at least another 2 panels. Your installer should know better.