200 watts of rich solar polycrystalline panels and 20a epever charge controller

[highdesertranger]

"But my beer is cold because the sun was out today"

That's the most important thing, After the cold beer everything else means nothing, LOL. Just kidding I also like an adult beverage at the end of the day.

Highdesertranger

 

[Camper]

Just hook it up and let the controller do it's job.

 

[XERTYX]

Yeah I know. I'm just a worrier. Chaos theory and so forth.

I also watch pots of water boil. 

Yeah having the sun keep drinks cold is so savage. You might remember I reviewed the frigidaire ice maker before. Well I had hoped it would work out and I could one day use solar to make ice AND run an ice cream freezer. Have the sun make me some ice cream.

 

[XERTYX]

Well I was hoping today to turn on a bunch of loads and see how many watts I could get out of my system with my new wifi com port adapter. But its cloudy as all get out and supposed to be all day. I did want to share this though. 

I had a peek via the app just to see how the solar panels were performing with the clouds. 90 watt hours produced before 10am. Not too bad I'd say.

 

[PeterPiper]

Not bad....but my PWM controller harvested 123 watts by 10am and it's raining.  

 

[XERTYX]

Haha. Nice. Are yours tilted or flat?

 

[PeterPiper]

Mostly flat.  And I was just kidding.  Haven't really checked today.
Planning to try  a MMPT controller soon and do some tests.   My gut feeling is the difference won't be much if any...but I'll see.

Did you make adjustments to secure your panels?

 

[XERTYX]

The only adjustment I've made so far is lowering the front support. I'm planning to add another cross bar in the front.

 

[Scott3569]

The only adjustment I've made so far is lowering the front support. I'm planning to add another cross bar in the front.

You know, We have the same vehicle.. My plan When I get to that point.. is to use square slotted tubing(metal of course) and put and extension of the OE rails( just need to watch your weight limit).. but the extension with go both towards the front of the vehicle and also ad a little width.

 

[XERTYX]

Yeah I wanted to go with metal but I didnt have the cash at the time. So I used wood. Also I was a little worried about the weight. I havent removed the rear seats yet and adding the battery and panels probably put me back over the weight I dropped when I took out the second row bench seat.

I had thought about going across the roof rack but i didnt want the panels to stick out past the rails, also I didnt know how I was gonna attach them then at that point. The original plan using U bolts was to add a folding leg on either side so I could detach one side and tilt it towards the sun.

 

[XERTYX]

THE reason series connected "POLYCRYSTALLINE" panels used with an MPPT charge controller is the best default choice.

It's back into boost/bulk charging at nearly 7PM on a cloudy spring day.

The panel has more surface area and the sky is still illuminated with a rather diffused light source. With a diffused light the panel with the largest surface area for collection wins. Assuming the entire surface is illuminated. 

Clearly.

 

[XERTYX]

So... earlier in the day my tablet was dead and I was just taking a peek at my charge controller. Those numbers weren't possible. I misread the PV voltage or PV amperage. OR I caught it right as the voltage fell and the amperage rose. Had to have been. 

So I put the tablet on charge enough to wake it up. And when the full sun was back out I took the following screenshots over the course of about 30 seconds. Pretty gosh darn remarkable. 

See for yourself.

 

[XERTYX]

The only sense I can make out of why my panels would exceed their rated wattage by more than 10% boils down to 2 possibilities. 1 the reading is wrong.

Or 2, when i bought my 2 pack of panels... and they were sold AS a 2 pack and arrived packaged as a 2 pack. Before they arrived I looked at the amazon page again to get measurements and I saw a review. The review said knowing that these are used panels they're a good etc etc.

I'm thinking these were not rated as 100w panels but were another brand and restickered as rich solar 100w panels. The MC4 connectors while supposed to be 10 gauge looked more like 16 gauge when I cut them off and soldered my own 10G wire. Maybe they were rated for like 120w or 150w and rich solar just peeled off the old stickers and rebranded them as their own.

When mine arrived they did have scratches and dents on the frame. But for the price AND I saw that they were supposedly used I couldn't complain. Then today the first really sunny day they over performed so I'm thinking these were originally Mfg to produce more than 100w.

 

[MotorVation]

I've seen my panels go over their rating at high elevation in between clouds. When the amps exceed the charge controller's rating it cuts the power back to the limit. I've only seen it happen a couple times. Too many amps are ok for my controller but I have to keep it under the rated voltage and all is well and fine

 

[XERTYX]

I'm not exactly at high elevation but I am up a mountain.... well in the Piedmont area at least. I'm about 20 miles or so of the Appalachian trail head.

But that was bananas. The controller is rated for 260w 20a 60v so all is well there.

 

[Scott3569]

Glad your solar system is working for you.. Where did you get the panels again?

 

[XERTYX]

These panels.

https://www.amazon.com/RICH-SOLAR-Pieces-Polycrystalline-Trailer/dp/B08DXL71K4

With this controller.

https://www.amazon.com/EPEVER-Controller-Regulator-Lead-Acid-Batteries/dp/B08GJL6FQB

I cut off the MC4 connectors and soldered them together in series with 10 gauge automotive copper wire.

 

[Scott3569]

was it a must to put the min series or was it personal choice?

 

[wayne49]

Series versus Parallel

Depends on the length of the cable run between the panels and the controller. Series doubles the voltage and with a higher voltage there is less voltage drop for a given run.

Series, a shadow on one panel kills the output from all panels.

Parallel, a shadow on one panel doesn't affect the other panel(s).

There are some older posts on these forums about having double the panel voltage helps in less than ideal conditions when a panel might have reduced voltage. IDK. With a percentage loss, 50% of 40V is 20V, where 50% of 20V is 10V.

 

[XERTYX]

Sorry I havent been around in a couple of days.

My reasons for wiring in series:
● Higher voltage in low light conditions.
● Higher voltage means smaller gauge wire is required.
● I used much heavier gauge wire than necessary in conjunction with higher voltage to minimize voltage drop.
● Practicality, as I am not a fan of MC4 cables wiring in series meant 2 wires running to my charge controller rather than 4 or some sort of junction box.

In the rain and very dark cloudy days i usually see at least 14 volts at the controller. If they were in parallel I would see 7 volts. Often times I'm still getting very usable amounts of charging under these low light conditions. 

In part I attribute series wiring to my success in seeing more than my panels are rated for on very sunny days. Several times especially when my battery is fairly heavily discharged and my fridge is running I have seen more than 200 watts from my 200 watt array. 228 watts was the highest output wattage I have seen. I'm very curious to try and run a heavy load when I find my inverter and see just how much oomph this system actually has. The controller is rated for 260 watts. I thought I'd never come near that in real world usage.