Mounting a Second Solar Panel On a Hawk

[Wallowa]

Phil, I'm confused when you say only a 58" long panel will fit. The panel does not have to fit within the rails. It just has to be narrower than the width of your Hawk, which is 84", is it not?

Vic...that was confusing, was not explicit...58" between rails so if I wanted a second panel mounted like the existing 160w then the attachments to the rails must be 58" as used by FWC in 2016...now you are correct with different mounting options I can go longer and wider behind the rear vent...

 

[Vic Harder]

Vic...that was confusing, was not explicit...58" between rails so if I wanted a second panel mounted like the existing 160w then the attachments to the rails must be 58" as used by FWC in 2016...now you are correct with different mounting options I can go longer and wider behind the rear vent...

Sorry, not trying to confuse you Phil!

I (and others here) use L-brackets to attach the solar panel to the rails. Size of the panel then matters not, as long as it AT LEAST as big as the space between the rails. Make sense?

 

[Wallowa]

Sorry, not trying to confuse you Phil!

I (and others here) use L-brackets to attach the solar panel to the rails. Size of the panel then matters not, as long as it AT LEAST as big as the space between the rails. Make sense?

Vic,

Yup...got that...don't worry about confusing me I do that on my own; in post #61 I was referring to my information being confusing not yours; my comment was poorly written...with the mounting towers I saw at AM Solar website and with the use of adhesive tape I do not need to use the Yakima rails and that opens up the possibility of adding a larger panel notwithstanding the distance between the rails and the need to mount on those rails.

After T-Day I will have a discussion with the techs at AM Solar and figure out if I am going Victron and the larger 200w panel; or defaulting to keeping it all Zamp with a 90w panel.

Take care...Phil

 

[Wallowa]

[SIZE=10.5pt]New wrinkle...adding a second panel...necessity of matching panel outputs; or you lose power output.. I enjoy learning but is there no end to nuances for solar system efficiency! So if I add a 200w [20volt] panel or a 90w [19 volt] panel to my existing FWC 160w panel the resultant will not be the total of the two panels in parallel but less than that. Ugh! Zamp only now makes the 170w; even if went with that I would lose output. Wonder how the controller now handles the portable 80w and my roof 160W?[/SIZE]



[SIZE=10.5pt]Any suggestions?[/SIZE]


"Mixing different panels, whether connected in series or in parallel, ALWAYS reduces the installed wattage.

Furthermore, if you don’t have any other option than wiring dissimilar panels, you should know that:

1) For series connection – the same current rating of the panels is more important.

2) For parallel connection – the same voltage rating of the panels is more important."
https://solarpanelsvenue.com/mixing-solar-panels/

Phil

 

[PaulT]

For ideal use, those caveats may apply. However, I have a factory installed Zamp 100 watt panel bertween the Fantastic vents. In addition I have a Grape Solar 160 watt panel mounting at the rear on my factory roof rack. I sometimes have also added a Renogy 100 watt first generation flexible panel or my Bioenno 120 watt suitcase panel. None of these are identical or even of the same manufacturer. I am certain that this is not ideal. However, the 160 watt adds more than the 100 watt Zamp panel and the Suitcase panel adds its own increment. when all three are attached.

I use the suitcase or the Renogy as either add on panels if the two roof mounted units need some help although I primarily carry those for my ham radio battery or my InTech Pursue trailer battery. One must acquire solar energy when the sun shines for however little it does in inclement weather especially in the winter when the sun is so low in the sky.

My solar charge controller is a 30 amp Trimetric PWM unit that doeesn't complain about the mismatches. As my system was acquired incrementally and I learned what I needed and could afford, I have made use of it. I didn't think that I could afford to start over at any time in the last 5 years.

Starting with a blank slate with what I know now, I would make different choices. Even though it has been scientifically shown that the bumblebee cannot fly, the bumblebee doesn't know that and flies anyway.

Paul

 

[Wallowa]

[SIZE=10.5pt]Paul...thanks for that...the pragmatic approach guided by experience makes sense every time...presently involved in installation of isolator/separator 7611 and ordered the Victron 712 with temp sensor... nibbling at the edges while deciding on a second panel..to be mounted where you put your second panel; I have 28 inches behind rear vent and the roof is 81 inches wide..[/SIZE]

[SIZE=10.5pt]The AM Solar Solar Grape 200w panel and the Zamp 170w are in the finals...big difference in cost! But in a penny in a pound.[/SIZE]

[SIZE=10.5pt]Phil[/SIZE]

 

[Jack]

When you connect panels in parallel you want to match Vmp voltages. However, all you lose is a few watts if they differ by a volt or two, and most panels run between 16 Vmp and 19 Vmp. If you save more than about 10% on the price of the panel, you are ahead. The Zamp handles voltages from 15 Vmp to 24 Vmp.

The Zamp controller can handle almost 500 W of panel, and for those of us with horizontal panels not living on the equator, our panels will never reach their full potential

It's much more important to match panels for series connection, and you also need a controller that can handle higher voltages (the Zamp does not).

 

[Wallowa]

Jack,

Thanks for that...My existing Zamp 160w supposedly has an output of about 18-19v [Zamp said all there panels have an 18v output but I noted the Zamp 90w Long has an output of 19.1v...wish I could get consistent, accurate data] and the Grape Solar 200w I am looking at has an output of 20.31v.....these will be in parallel...from what you said the loss of watts will be very slight....

Thanks again....

Phil

Ps...The tilt option from AM Solar mounts looks inviting...necessitating a ladder...

 

[PaulT]

I have the AM Solar tilting mount and they do make a significant improvement in performance when I am able to use them.
The first problem is to plan how to orient your truck. You can tilt the panel either toward the front or the rear of the truck to maximize solar energy acquisition or you can tilt to the south to optimize energy acquisition.

The difference can be significant in that maximum energy is acquired when the panel is perpendicular to the sun’s rays but that requires frequent moving the panel to remain perpendicular.
If you aim the panel south elevated to your latitude, you will optimize energy acquisition over the day without having to reorient the panels.

I have found it best to orient the truck north to south and tilt the panel south prior to popping the top. I will get more hours per day of generally increased solar energy collection. In addition, I need not get a ladder several feet higher to reach the panel tilt mechanism after the top is raised.

I found I was spending scarce camping time to maximize energy collection instead of enjoying my environment and company. For me, having more solar panel watts than required allows me to pay attention to the reasons I go.

Paul

 

[Wallowa]

Paul...

That makes sense ....and finding a suitable spot to park N/S is no small feat...only the rear panel will possibly have the tilt option...not expensive and at the rear easy to reach...but I concur on KISS approach...that is why I seldom use my FWC 80w Zamp portable...chasing the sun cost a lot of time...

Phil

 

[Vic Harder]

KISS? Park the truck with the nose facing North and only leave the front popped up when you leave it for the day. More sun and rain/snow slide off easier.

 

[Wallowa]

Vic,

Ha, that is an excellent example of a KISS process that helps with the solution...never thought of that...pointing the truck North may be another issue...but doable.

I will assume that a snow load on a partial raised roof will not cause structural damage to the roof [bowing it and causing permanent distortion]?

Phil

 

[Vic Harder]

Dunno Phil, the snow is light and fluffy here

 

[JaSAn]

. . .
I will assume that a snow load on a partial raised roof will not cause structural damage to the roof [bowing it and causing permanent distortion]?

When the roof is up it is supported along the two ends by the lift panels. I don't see what would be different: one end is supported up across its width by the lift panel and the other end is supported across its width by the camper wall.

If you are sleeping up there I would add another support for the roof on the overhang (I do that anyway).

 

[Wallowa]

Just talked to FWC service department asking about the use of Overland panels and not Zamp...cost [to who?]; lighter weight and better capture of solar energy even when cloudy..said flexible panels also a plus [weight?].

Why would the Overland panels be more effective during low sun conditions? Not just the brand of cells used but why are these cells more efficient?

FYI...FWC only sells and installs [OEM] 160w Overland panels.

Call/email into AM Solar here in Oregon on the purchase and install of either a Zamp or Grape Solar panel as my second panel.

Phil

Ps... Jasan... Snow weight or even high wind on a tilted roof [back end down] would seem to me to put a load on front panels in two directions; vertical and lateral...I think they would not take kindly to a lateral load....but I always wondered how the advertised maximum roof load of 1,000 lbs. could be supported by the thin front and back panels....

 

[wicked1]

Hi, I just got back from a week in the forest. Love my camper .

About Overland being better in low light (or any new panel w/ the sunpower gen 3 cells)...
You'd have to do some googling for the technical descriptions, but they are bottom contact wafers, which avoids having wires over the top of the cells. Also the way they built the anode and cathode is different.. It allows them to drop to a lower voltage before they cut off completely. I think they were just the most recent to release a new cell technology. I'm sure another manufacturer will release something better soon, as solar is developing fast at the moment.

I can say from my last weeks trip, my overland portable panel produced power for a couple hours at the beginning and end of each day, when my 100w Zamp panel was not making any. I was doing a lot of testing (Unplugging each of the panels, one at a time, all throughout the day, while monitoring the voltage and current. Just to see how they were performing)

 

[Wallowa]

Hi, I just got back from a week in the forest. Love my camper .

About Overland being better in low light (or any new panel w/ the sunpower gen 3 cells)...
You'd have to do some googling for the technical descriptions, but they are bottom contact wafers, which avoids having wires over the top of the cells. Also the way they built the anode and cathode is different.. It allows them to drop to a lower voltage before they cut off completely. I think they were just the most recent to release a new cell technology. I'm sure another manufacturer will release something better soon, as solar is developing fast at the moment.

I can say from my last weeks trip, my overland portable panel produced power for a couple hours at the beginning and end of each day, when my 100w Zamp panel was not making any. I was doing a lot of testing (Unplugging each of the panels, one at a time, all throughout the day, while monitoring the voltage and current. Just to see how they were performing)

First good to hear you love your rig! Thanks for insights and informative look at construction of panels. Will investigate "Gen 3" cells.

You say the the Overland portable [100w?] was more effective than the Zamp 100w. Could the difference have been that you were orienting [moving] the Overland toward the incoming solar and the Zamp [assuming it was a fixed panel] was not repositioned and therefore not facing the sun during AM/PM low light?

Take care,

Phil

 

[wicked1]

You say the the Overland portable [100w?] was more effective than the Zamp 100w. Could the difference have been that you were orienting [moving] the Overland toward the incoming solar and the Zamp [assuming it was a fixed panel] was not repositioned and therefore not facing the sun during AM/PM low light?

Take care,

Phil

No, the day I was doing these tests, I had them both laying flat. The portable was on the ground, but the sun situation was the same. The overland portable is 130w, but I don't think that is what made the difference. I was getting zero output from the Zamp.. it just didn't work w/ the level of light. It was about 9am before it started making .1a on its own. Overland was making that at 7am, and 1a by 9. At mid-day their output is about the same.. Overland a bit better, but it is a 130 watt panel. So, the benefit really was at low light conditions.

 

[Wallowa]

Zeroed in on what panel I am going to buy and how I will mount it.

Talking with Rodger at AM Solar was not only very informative but he was very helpful.

Getting a quote hopefully this week or next for the Zamp 170w panel, 4-mounting brackets for that panel [L feet 35mm rocker mount] and Sikaflex 221 sealant. Brackets use 3M VHB tape; and, 221 is insurance.

Wiring is standard Zamp SAE, so all I need is a splitter with dual SAE female plugs leading into a male SAE to plug into the single female FWC SAE plug on the roof of the Hawk.

Voltages and watts of panels all "fit" and will of course be in parallel. This array will give me 330w and about 18a input. If needed I still have my Zamp 80w portable to plug into Hawk back wall SAE outlet.

Rodger said that the phones have been ringing off the hook since March and the 25 employees are swamped. Perhaps, just perhaps, folks are beginning to 'wake up' and wanting to be more self-sufficient.

Phil

 

[wicked1]

Rodger said that the phones have been ringing off the hook since March and the 25 employees are swamped. Perhaps, just perhaps, folks are beginning to 'wake up' and wanting to be more self-sufficient.

Phil

That's definitely the case.. Tons more people going out because they don't want to fly w/ Covid around, etc.. That's good because more people learning to enjoy the outdoors and take care of themselves is great. But, OTOH, there are some complete a-holes just destroying nature out there. Every camp site I've seen this year has poop and TP just sitting on the ground 10' from the fire ring. There's graffiti on rock formations. Trash everywhere. I understand people not knowing what to do, and maybe that excuses the poo and tp close to camp, but the trash and graffiti, and just destruction of nature.. WHY!?!?!??!??? I guess they don't understand there is no one out there to clean up after them.. Those rock formations weren't built and can't be replaced.

I just bought my first camper this year because of Covid. (But I've been a lifetime backpacker and have been renting truck campers out west for the past 10 years).