new panels with new charge controller will not charge.
- Thread starter DixieMtCR
- Start date
Today, I took the time to rack up all of the 5 panels on the roof in a temporary array. Unfortunately, the slant of the roof faces SW. It rained and snowed most of the day. When I finally got the panels racked and mounted, and wired in, it was 2pm. but with all 5 panels, the controller could not pull the panel voltage down. Open Circuit Panel Voltage was 22.3v. open panel current on 10A scale was 1.3A. As I was cleaning up my mess for the day the sun came out briefly and the controller registered 3.2A from the panels. The controller was pushing about 5amps into the batteries.
Correct. Thanks.
If the panels got full shine, I would expect more than 65W.
I would certainly hope so for the cost. Somehow I had this feeling that a 500 watt system at 12 volts even with 50% proficiency might put out 200 or 250 watts. I must be mistaken somewhere.
MisterSandals
Participation Medalist
I tried reading back and nowhere did I see the results of measuring the voltage and amps from each of the panels. Its hard for me to consider blaming the SCC without a basic test of each of the panels in full sun.
So they advertise the 500 watt system for 40 amps and 40 amps for the controller. And they say that it's 96% efficient. Let's give them the benefit of the doubt and say 400 watt instead of 5 that's a lot below 96%. So that would be four kilowatt hours in a 10-hour Sun day. That would be a 31 amps average out over the period of 10 hours. Sometimes a little less sometimes a little more. And that would be the panels and the controller running at full bore. The most I have seen going out of the controller is 5 amps and that was momentary.
Not sure where you live or even have a clue but I live in the very northwest of Oregon. We're still having lots of rain and even snow at times had some last night. The sky has been cloudy but it was sunny most the time today. Certainly not warm outside at 36 degrees. I worked outside all day. It will be a few months yet before we see full hot sun at 90° to the panels. Sorry I can't give you any readings of perpendicular sun at full blast. It's just not going to happen till about June. In the meantime in a day and a half my grandmother total of power production is 320wh. If my calculations serve me right having five LED 17 watt bulbs running in my house in the evening from dark till 10:00 I will be in a deficit from the charge current that I get each day.
You don't understand this stuff at all. 96% efficient means the SCC is up to 96% efficient at turning incoming power into battery charging power. That's it. It in no way implies you should get 96% of 400 or 500W for 10 hours per day.
The only time panels produce their rated power is at 25°C and 1000W/m2 of solar radiation hitting the panels. If you're not perpendicular to the sun, you get less. If the sun is not nearly directly over head, you get less. If the sky isn't perfectly clear, you get less. In your imaginary scenario, 31A average is a fevered dream. MOST of the time, it will be well under that. RARELY will it be over that, and in your location, you may NEVER get a full 40A.
There isn't a place on the planet that gets 10 hours of solar productivity on a fixed array. My system is in sunny AZ with a thinner atmosphere, and I don't get anywhere near your imagined 10 hours. If you have a 2 axis tracking mount, you can get close. I picked a place a little bit SE of Portland:
I tilted the panels at 45°. The AC Energy column assumes a 15% loss due to conversions. 49kWh/month = 49/28 = 1.75kWh per day average.
If you mounted them at less than 45°, your production will be lower.
I think your expectations are way off base, but I also think your system is under producing. Something is wrong with your system.
You need to check Isc on each of your panels.
The only time panels produce their rated power is at 25°C and 1000W/m2 of solar radiation hitting the panels. If you're not perpendicular to the sun, you get less. If the sun is not nearly directly over head, you get less. If the sky isn't perfectly clear, you get less. In your imaginary scenario, 31A average is a fevered dream. MOST of the time, it will be well under that. RARELY will it be over that, and in your location, you may NEVER get a full 40A.
There isn't a place on the planet that gets 10 hours of solar productivity on a fixed array. My system is in sunny AZ with a thinner atmosphere, and I don't get anywhere near your imagined 10 hours. If you have a 2 axis tracking mount, you can get close. I picked a place a little bit SE of Portland:
I tilted the panels at 45°. The AC Energy column assumes a 15% loss due to conversions. 49kWh/month = 49/28 = 1.75kWh per day average.
If you mounted them at less than 45°, your production will be lower.
I think your expectations are way off base, but I also think your system is under producing. Something is wrong with your system.
You need to check Isc on each of your panels.
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