DIY grid-tied system 980 W 12V set up

I live in N. Phoenix! The panels are new since I bought it from Amazon warehouse. They are open box item, They all have a factory 25 years warranty. Some of them never open and Bouge RV and SunGold Power are a brand new from the vendor, yet it only increases 1.00 kWh. The inverter is a brand new as well, not an Amazon warehouse deal.

The temperature may be a factor, but I don’t think AZ sun makes the panels underperform. For example, renogy operating temp: -40°F to 176°F. Last summer the hottest day was under 120°F.

Voltage from PV panel into inverter will show how close to Vmp it is, then you can calculated how many watts are being delivered from each panel.
Do you have an ammeter that can show current from one panel? Show AC current produced?

I have an Etekcity ammeter and wheel to V~, right?

V~ gives AC. We already know that is 120Vac +/- or else 240Vac. Should be 120Vac from your link.

You want V --, which is DC.
Then probe the PV panel terminals of the inverter.

It's a clamp meter for AC, so you can measure that (around a single wire of the AC cord, not both wires at once.)

Does it measure DC? Perhaps have a banana terminal for amps?

Thank you @Hedges I will do it when the sunrise and check every single wire? Do you know what kind of range I am looking for 100 W 12 V panel?

What do you mean "Does it measure DC? Perhaps have a banana terminal for amps?"

Except for TP, all the panels were 22 Voc and 18 Vmp.
If you get 18V at the PV terminals of the inverter, it is at maximum power point and is receiving full power from them, however much that is based on the sun they get. If not, we will estimate how much power from a PV panel IV curve.
(Find a curve for your panels or similar ones. At the voltage you measured, what current is expected? Multiply to get DC watts.)

With the clamp ammeter around one AC wire, you can read AC current. Multiply by 120V and see how that AC power compares to whatever display you were reading.
Oh, you were quoting kWh? Where did you measure that? Just for this one inverter, no loads?

Some DMM can measure DC amps. Most clamp meters can't because it requires a more expensive Hall effect sensor, not just a transformer.
Does the data sheet or manual mention DC amps?
My DMM has a terminal for volts/ohms, a terminal "common", one for 10A, one for some mA. I put the test leads in the appropriate terminal.
If yours has a terminal for amps, you may be able to measure DC short-circuit current of the panel (disconnected from inverter) or connect meter in series between panel and inverter to measure the DC current it draws.

AZ wan said:

I live in N. Phoenix! The panels are new since I bought it from Amazon warehouse. They are open box item, They all have a factory 25 years warranty. Some of them never open and Bouge RV and SunGold Power are a brand new from the vendor, yet it only increases 1.00 kWh. The inverter is a brand new as well, not an Amazon warehouse deal.

The temperature may be a factor, but I don’t think AZ sun makes the panels underperform. For example, renogy operating temp: -40°F to 176°F. Last summer the hottest day was under 120°F.

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I'm in E. Mesa. I thought if you were close, you could swing by and grab my 1000W 12V unit and see if there's any difference.

You need a DC clamp meter. That one is only AC. You can only measure voltage. You want to wrap a DC ammeter around one of the solar panel wires and measure the current flowing through it to confirm it's actually doing something.

AZ temps right now don't impact panel performance adversely this time of year.

I ran a PVWatts simulation near I-17 and 101:



Assuming your panels are flat with little or no tilt, you should get 3.06 * 980= 3000 Wh/day.

I also ran it for a tilt of 20° assuming your grid tie is at a steeper angle, and it's 4.5, so your grid-tie array array has 50% more potential just from a difference in angle.

I need to buy a DC clamp meter first since I only have AC meter. They are not cheap and about $40, twice from my AC only clamp. I live in 85032 Tatum and Bell.

I followed the solar angle webpage adjust the three panels two weeks ago; I didn’t see a huge difference. I reset and lay on top of the patio with little angle. I worry it will fly away during monsoon season. All my panels do not attach to anything because I can remove and clean them easily. It is my first solar panel project.


Solar angle

@Ampster I created this post at the beginning of the week about my system. It includes my spec., house pics, and system size. Check it out!

snoobler said:

Link #5 in my signature. Yields # of solar hours by month for your location, panel orientation and tilt. Take that number and multiply it by your array wattage, and that's your average daily yield. It factors in average weather effects as well.

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Thanks for #5, just used to find the angle option I want for my south facing test setup

Also worth checking out https://www.solarpaneltilt.com/