Hello Tim, I am back. Everything is connected and ready except the panels. They will be here tomorrow or Friday. I am sorry If I am beating dead horse but I am still not 100% sure I will ground the panels right. Close to the beginning of this thread, I believe you said it would be fine to connect the panels, battery, combiner box and inverter all to my house ground (as you know my house ground is a copper pipe outside). So I trust your experience and I was planning on doing that. However, an inquiry i made to a big well known solar company in US finally replied to me. Their designer team sent me following. Needless to say I am confused again. I tried everything I can to find someone to drill 2 meters in this clay rock hard. It is not possible. Even if possible, the separate ground rod CANNOT be 30 feet away. My lot is to small to allow that. So I see only 2 options. Ground the array, inverter etc with the house ground or don't ground the panels at all. In Aruba we get a few small storms in November December and maybe one lighting, then no rain only sun for many months. So maybe I worry to much. Sorry to bring this up again. If this would be your house here in Aruba with like lava rock soil hard to penetrate, what would you do? Thank you. I forgot to add that tomorrow I am paying a consultation with the best solar company here in Aruba to have their "expert" come to my house and recommend a solution. Can't wait to hear it.
Last check for ground plan of my offgrid system
- Thread starter jimmy747
- Start date
timselectric
If I can do it, you can do it.
- Joined
- Feb 5, 2022
- Messages
- 18,615
I disagree with everything they said.
But different people do different things in different parts of the world.
What I have recommended is what I would do. If I lived in your house.
No matter what part of the world. Personal safety is the goal.
If a short to a panel frame happens at the array. That 30' (they recommended) between the two ground rods. Becomes a dangerous place for people to be.
I'm wondering how critical panel grounding would be if the string VOC is 74v?
timselectric
If I can do it, you can do it.
- Joined
- Feb 5, 2022
- Messages
- 18,615
It depends on what equipment it's connected to. Most high frequency budget AIO's have AC voltage on the PV conductors.
The PV voltage isn't really the Hazzard.
They are connected to victron SCCs.
timselectric
If I can do it, you can do it.
- Joined
- Feb 5, 2022
- Messages
- 18,615
Since they only connect to the DC bus. It could be considered less of a Hazzard. While 74v is still dangerous. The probability of inadvertently becoming part of the circuit is very low.
Thank you Tim for the quick reply. I totally agree with you: "Personal safety is the goal." I won't chase this ground thing anymore.
I am waiting today for my panels delivery like a mother expecting a baby!!!! lol. Have a great day.
Good evening. I paid an experienced solar company here in Aruba to come to my house for an assesment. What he said was shocking no pun intented. He said that they did 4 homes in this neighborhood and NONE of them have panels connected to a earth ground. I asked why. He said an additional ground rod could cause ground loop. And should a lighting hit your panels you don't that go on your house ground.
Chances that the panels get hit by lighting is very small in Aruba. My house is surrounded by very tall palm trees, electrical poles, in his opinion lighting would hit that before going for the panels. He also said we get one storm with thunder and lighting once a year. When the storm come, we recommend customers to disconect the panels. Then I asked if someday I want my house to pass an electrical inspection. He said that most of the time he is present with inspector when the inspections happen. It is not a requirement to ground panels. WOW WOW WOW, I guess no NEC rules here. Despite his recommendation, I feel that your recommendation is the best one. you said "different people do different things in different parts of the world" true. But that doesn't mean it is the safest way. I will ground my panels directly to my house ground. Thank you Tim.
First day of free AC ! YES! Just wanted to share with the members that the Growatt SPF 5000 ES is working perfectly as designed. I am testing on the ground but soon they will be on the roof. I used a recommendation I saw here in the forum to at least have one battery. I have one Growatt 2.5Kwh. It is amazing to have the AC running flawlessly and watch the Growatt display use some battery energy when clouds pass by and quickly return at charging the battery when the sun return. Absolutely love it. Any questions on my setup I'll do my best to help. Thanks to all for the help! 
timselectric
If I can do it, you can do it.
- Joined
- Feb 5, 2022
- Messages
- 18,615
Congratulations
Good morning. Everything is up and running now for about 2 weeks. I can run AC during the day and recharge my Growatt 2.5 Kwh battery. I have 2 questions. 1) What percent should I set in setting 12 go back to grid power? What is a healthy setting for the battery? How low can we go? I currently have it set to 30%. 2) In the afternoon around 2 pm I reach full sun directly pointed to the panels with no shade. The dashboard shows a maximum 1,422 watts. That is like half of the 3.3 KWh (6 panels of 565 watts). I measured each panel. average 45 volts. Measured total of 270 volts. Do we only get half of what we buy and install? Am I missing something? Thank you.
Attachments
timselectric
If I can do it, you can do it.
- Joined
- Feb 5, 2022
- Messages
- 18,615
It's really personal preference.
Based on how much reserve you want to keep.
This time of year, is more prone to grid outages, for me. And production is low. So, I keep my batteries above 20%.
In the summer, I let them go down to the single digits. Because I generally only need to get through a single night in an emergency.
A lot of things affect production. 50% is pretty common for winter.
The sun is lower and has to travel through more atmosphere. The angle isn't usually great. And days are shorter.
Basically, winter production sucks.
Thank you Tim, I will add panels when possible. I still like my little system, every night I go to sleep the AC starts off on battery so free AC during the night to the discharge limit I set it, then starts using city electricity. I expect a nice reduction on the bill at the end of the month. We will see. But for sure every hour my AC runs off the grid is $ saved! Just woke up from a 2 hours nap in cold AC and the battery is 100% ready for the night. Love it! I used to love clouds to help reduce heat in Aruba. Now I hate them!!!!! Thank you again for all the help.
Good morning. I am ready to add 2 more panels. Can you please let me know when calculating maximum voltage for the Growatt SPF 5000 ES. It says max 450 VDC. So. right now the inverter is showing 270 volts but as you explained it will increase as we get closer to summer. So to not overload my inverter, do I use VOC at STC or NOCT? If I calculate 8 panels at VOC of 50V that is 400 volts so that should be fine. Am I doing this right? I am asking you Tim because you know very well this inverter. Thank you!
timselectric
If I can do it, you can do it.
- Joined
- Feb 5, 2022
- Messages
- 18,615
Always, and don't forget temperature compensation.
Voltage goes up as temperature goes down.
Could be close for cold temperatures.
What is the record cold temperature for your area.
(Sorry, if this has already been discussed. I'm old lol)
Correct
8 panels in series (8s) at 50 VOC, would be 400 VOC.
Similar threads
