Public Discussion Forum

I have been planning a new solar array on 401Play for about a year and finally got around to it. The old 2017 version was 4 275 watt panels. It worked fine but it was too small to support our demands and impossible to clean under without major disassembly. I was able to find 455 watt panels that were only a little larger but still leaving room for access to all sides, especially down the middle to the radar arch. The outboard side is hard to get from the top but still possible.

My biggest design issue, aside from space for maximum power production was attachment. I didn't want 50 plus holes in my hard top like I had. The original panels were all screwed in and sealed with 5200. They sat 2-3 inches above the roof leaving no room to clean under. Every time it rained I would get dirt, algae and oxidation running down the side of the boat. My solution to that was to hinge the panels so they can be flipped up allowing access for cleaning and maintenance. I found roof top, anodized aluminum, brackets that were made to do just that. They came with nuts and bolts for pins but I wanted toolless access so I replaced the pins with clevis pins and hitch pins. The panels can now be easily lifted, from either side, and propped up, in a secure upright position, with the same clevis pins used to hold them down. I happened to have 2 left over Bimini supports that work perfectly to secure the panels upright.

Tilting the panels works great and I can have full access within a couple minutes. The attachment is a bit of an experiment. I saw countless YouTube videos about RV's that attached panels to their rigs with double sided 3m VHB tape. I was skeptical at first but the more I watched the more sense it made. The convincing thing was the people who did follow up videos a year or 2 later and it was still holding with, maybe, minor issues. Maybe the follow ups were the exceptions and the failed one never followed up. There is no way to know without reaching out. However, thinking about the forces, I figured as a boater I see winds in the 20-30 knot range all the time but only occasionally do you see 40 plus winds. An RV running down the road at 60 into a 15 mph wind is seeing cat 1 hurricane forces all day long. I wanted a little more scientific evidence so I also ran the math, specific to my panels and bracket sizing. If 3m is honest about their specs, it makes sense in over 100 mph winds. Frankly, if I'm seeing 100mph winds, my panels are the least of my worries.

If you're not familiar with VHB tape, its double sided with foam in the middle. So if stresses start working on the joint, the foam absorbs most of movement just like a snubber or bridle on an anchor. I used a version of the tape that is supposed to be moisture and UV resistant but I sealed all the bases in Lifecaulk to protect the tape joint. The Lifecaulk can be more easily removed if need be and it remains flexible to work with the foam in the tape. All of the brackets are easily inspected to be sure this is all working as planned and worst case scenario, I can always put 50 plus holes in my roof.

As I write this the controllers are producing just over 30 amps, at 10:30am, and supporting my 11 amp house load and putting 19 amps into the LifePO4 batteries. If this keeps up, I'll produce about 10kwh today. All toll, I need about 6kwh to re-fill the batteries and supply house today.

The next project is to install the Multiplus 2 inverter. It has an automatic second AC output, that only runs when the batteries are full to make use of excess power. I'll wire that to my 120 volt water heater. This will almost eliminate any need for the generator for all but Air conditioning.

Attached are some pics of the installation. Most everything used was from Amazon.

Joe and Linda

401 Play

2009 Selene 55078

Hi Richard, I figured that too. The calculation was spot on with the old panels over the last couple years. I attached a pic of the old output from one side and assuming same on the other side it's right there. I also attached this weeks new output. It was mostly the same weather except for rain 2 days ago. The first day after the install was complete, I had 4.7kwh on one side and 5.5kwh on the other. I also, have to keep in mind these are brand new TopConn panels. They should be more efficient than the old 2017 panels, but they will definitely produce less next year. If I'm still short, I can also add some over the pilot house. The goal was to reduce gen use and this should get me most of the way there.

Joe and Linda

401 Play

2009 Selene 55078

Joe..great solution for the hardtop. What are the brand of solar panels you landed on? Did you consider surface mount panels on this go around? We are in the build phase and I need to land on my solar panel wattage and type so the yard can install the controllers properly. Good looking installation. Thx! Chris

Chris P

Selene 6050 - Full Circle

Hi Chris, I was able to go with 455 watt, Canadian Solar TopCon panels. That left me about a foot fore and aft of the array and about 18 inches down the middle. The outboard side is tough but I can get a footing between the panels and the hand rail with the panels in place. Not a lot of room but its enough to make everything serviceable. Canadian Solar makes higher output panels, in the same foot print but now you're getting into commercial grade and have to buy a minimum of 10 panels. The boat is a 55 but I think the hard tops are the same as the 53 and smaller than the 60.

Joe and Linda

401 Play

2009 Selene 55078

Congrats on the installation Joe.

I would have never thought adhesive would hold the pressures of the solar panels in wind. Really cool that they do and great that your panels fit so nicely! One word of advice to consider (which you may recall from my installation): I put down 12-year rated vinyl wrap on my roof all the way to the drain channels. It doesn't show from below (thank God - no one will be paying me for my vinyl laying skills), and it prevents oxidation and sluffing of the roof's gelcoat onto the rest of the boat.

As to the 455W x 4, that's great! I have 410Wx4 and what I wouldn't give for the extra 180W. It can make a difference! What is your MPPT setup? I have two Victron 100/30s split to pair the two front and the two back. You must have at least the 100/50s? My 100/30s can be saturated if my arrays are producing their maximum rating, I've only seen that once, but it was a glorious feeling to see 60A being pumped into my system! 😁🌞 (My thanks again to Mark Tilden for showing the way in array installation!)

Great installation!

Steve

Kallisto 5369

Hi Steve, I agree with you on the adhesive so only time will tell. I kept the old lag bolts, just in case. For controllers, I had Victron 100/30, for each side, but I thought that might be too close. So I went to 2 100/50s and oversized all the wiring to reduce loses. The panel leads are 12awg and I can't do much about that but they are short, so loses should be low. The original install had 10awg for the 20 or so foot cable run from the panel to the controller. I added a short run of 6 awg after the Controllers to the distributor. The Victron distributor is 1000amp and fed with 4/0, from the batteries. That 4/0 cable was already there to power the davit. So I re-arranged that to basically have a large buss on the flybridge. The Victron Linx Distributor makes a very nice clean install that is all separately fused for each connection.

Joe and Linda

401 Play

2009 Selene 55078

Thanks Joe for the details. It sounds like you and Steve both have great set ups. I am intrigued by the vinyl wrap concept - Steve do you have a brand name? What maintenance do you need to do for this? I am assuming you have raised panels as Joe does? Let the sun shine in!

Chris P

Selene 6050 - Full Circle

Hi Chris,

I believe the vinyl wrap brand was Avery.

Yes, I can pivot my panels up as well (and did during the install of my new Simrad radar).

Steve

Kallisto 5369

It looks like we are all drinking from the same koolaid trough. On Shangri-La, the flush mounted Solara panels installed in 2016 were not up to the challenges of tropical conditions close to the equator or anywhere south of the Bahamas. They overheated and lost efficiency. That is where we were for three plus years and we needed our solar to work. So, we switched to raised panels and covered the hardtop of SL with every square inch of new solar array possible, leaving only a narrow walkway down the middle of the hardtop for access to the radar equipment and mast. I could sell electricity to sailors! Generator only runs when we need washer, dryer, hot water heater, dishwasher, AC and scuba air compressor. But not as freely as our friend in St. Barts, Hugues Poirot, who owns a boat yard there. His boat, appropriately named Solar Fox, carries around 3.5kw of solar! He added an entire canopy of solar over his aft bridge deck to provide shade and SHOCK (electricity)!

The attached photos show our mounting plan, requiring us to drill exactly ZERO holes in the hardtop. The SS crossmembers are supported outboard by the SS safety rails. The middle SS foot used for support is held in place by a small circular 3M adhesive pad. The panels are on hinges and lift from inboard to outboard for service and cleaning the hardtop if needed. Actually, we left enough room under the panels to get a mop on a long pole under them just for cleaning purposes (pure luck!).

I will be using the same or similar plan for the solar array on 6047 which is in build now, to be completed Q1 2026. I return to the yard in December for another look at progress, and the Grand Opening of Selene Yachts’ new building. I will take with me any needed specialty hardware from the USA (probably only the SS feet) and a few other items for installation there. I will take a Maritime Starlink cable and other needed wiring, not readily available in China, to pull to make installation in the USA easy when she arrives.

Jack

Jack Burgess, Shangri-La 5388

I did not mean to insult or insinuate anything by using in my last entry the phrase “drinking from the same koolaid trough” or to suggest that any of my fellow Seleners (and certainly not me) have any proclivities that suggest lunacy, nuttiness or silliness to any degree whatsoever. To the contrary, we are all clearly goal oriented individuals with the ability to focus properly on a problem and its solution. If there was an underlying suggestion in the “drinking” reference beyond the obvious, it was to suggest the “cup of wisdom” as the drinking vessel, symbolically representing enlightenment, spiritual insight, and profound knowledge.

And if the above is believable or meaningful to you in any way, my tongue is firmly planted in my cheek, waiting for you to explain how and why. (Hmmmmmmmmm)

Jack

Jack Burgess, Shangri-La 5388

Hi Jack, I understood it as we are all thinking about how to solve a common problem. So no offense taken. Multiple people can look at exactly the same problem and parameters and come up many ideas to solve it. That's why I wanted to introduce the possibility of using the 3m tape as an alternative. If it works, it would be a game changer for many and I'm looking forward to reporting, one way or another, after another hot Summer to see how it holds up because heat is definitely something that will degrade that product. I like your design as well and may be my alternate if this fails because I really don't want the holes.

Thanks

Joe

Joe and Linda

401 Play

2009 Selene 55078

Hi Joe -

The entirety of my last post on this topic was tongue in cheek, attempting to inject a bit of levity into what has been, for Terry and me, nine days of Covid induced delirium, courtesy, I believe, of at least one of the 800 or so airline passengers who joined us on our travels home from our yard visit in China (and then a few awesome days in Hong Kong). We are recovering and I just returned from an hour long bike ride, my first exertion other than coughing for quite a while. Terry is a couple days behind me, but feeling better also. She is starting a batch of fig jam with the figs I picked on my bike ride.

As to the merits of using adhesive for your application, I bet it works. On our solar install completed in December ‘24, the center SS feet supporting the SS cross members are neither screwed into the hard top nor attached with 5200, but are held in place by both gravity and small 3M adhesive discs that keep them from moving around at all. Eight months in they are firmly in place and I expect they will remain there.

In the future, I counsel you not to take what I say seriously, or, if you choose to, do so at your own risk.

Best - Jack

Jack Burgess, Shangri-La 5388

I've run into an interesting problem with this installation. The panels, in series, will produce about 70-75volts at about 13 amps, during full sun. The leads from the panels to the controllers are 10awg, capable of twice that current. For each side of the array, I installed a double pole 25amp C type breaker. This is more to be able to stop the flow from each half of the array as opposed to current protection. The first couple days one breaker would pop at some point during peak sun. The other was fine. I thought I had a bad breaker so I replaced it with a 40amp of the same C type. I know that is not correct for the 10awg but all I had and I know I'll never see even 15 amps on the circuit. I have 30s on the way for a better fit to the wire. Anyway, that took care of the pops but then the other one started doing the same thing after we moved from our dock.

I looked at the history, in the Victron app, to see what the current was right when they popped and they were both right at round 12-13amps just before it went to zero. I replaced the other side of the array with another 40amp and they are both running great now. The only thing I saw was the voltage was fluctuating a lot, maybe 10-15 volts very quickly, due to shading, just prior to the breaker kicking out. This was common on both and happened repeatedly over a couple days. The breakers are C type breakers which are better rated for surges so I'm not sure what's up. It will be interesting to see if the 30amp breakers still work ok.

I'm thinking about just installing 2 double pole isolation switches instead. Maybe adding an inline fuse at the panel array but that's more connections to go bad overtime. I'm not even sure of the value of current protection on the series array. If they were parallel, yes. In series, it can't produce more then normal output current unless its hit by lighting and that's a whole other issue.

Anyone have any idea about this?

Joe and Linda

401 Play

2009 Selene 55078

Hi Mark, I used the existing wiring from the previous install. I've thought about running them independent since I have the old smaller controllers but I'm not sure how much I would gain. I plan to look at that closer.

Joe and Linda

401 Play

2009 Selene 55078

Hi Joe -

Can you supply the model/manufacturer of the 25 amp circuit breaker that was tripping?

- rob

Roadrunner

2007 Selene 49 deep hull 48-029

Hi Rob, It is a DZ47Z-63 c25. I attached a pic.

Thanks for any insight

Joe and Linda

401 Play

2009 Selene 55078

That is an AC circuit breaker, you don't want to use it on a DC circuit such as a solar panel. The data sheet for the breaker makes no reference to DC use at all. Without knowing how it works internally it's not likely we can determine what caused it to trip unexpectedly.

But it is a fire hazard due to internal arcing.

Use DC-rated breakers for the DC loads - they are designed to handle the arcing.

- rob

Roadrunner

2007 Selene 49 deep hull 48-029

Thanks Rob but I'm confused. I considered that but it has DC500v stamped right on it. Even the box says it's DC.

Joe and Linda

401 Play

2009 Selene 55078

If the box says it's a DC breaker then I will absolutely believe the box. And good point about the DC500V. When I looked up the breaker numbers it came back as an AC unit; I did some more digging just now and came up with other manufacturers stating that is a DC breaker. Data sheets are inconclusive, I could not locate that specific manufacturer's data sheet, so I'll believe what's on the box and printed on the breaker.

I wonder how it is designed internally?

For large DC breakers I've always used Blue Sea Systems, they have a 25A DC breaker but it's only good up to 80 volts DC.

- rob

Roadrunner

2007 Selene 49 deep hull 48-029