Best attachment and set-up for solar panels

[Yarome]

1 hour ago, DuneElliot said:

The 10A fuse was provided as part of the set-up and complete package from Renogy. I would surmise that if I didn't use it and something happened my warranty would be void.

That's entirely your choice. One 10A in-line (panels to controller)... that means your only option is to run all 4 in a single series array.

[Sehc]

Protective diodes in the panels also fail. My 4x 100W renogy panels are wired in parallel. They have the factory 10AWG wire with 8AWG extensions. Each panel has a 15 amp fuse before they tie together in the combiner box. If there is a failure in one of the panels, the fuse for that panel will open due to back feed from the other three panels. There are inline fuses that connect at the MC4 connectors, I use different fuses and have those MC4 fuse holders in the parts box waiting for yard sale. We must, must, have a fuse at the positive battery terminal protecting the wire from the controller to the battery. With the typical 12 volt solar with the properly sized wires, there is no real need for other fuses. The panel's output is limited and the wires should be sized to carry the full short circuit amp without heating. During a short, the battery is unlimited until exploding or dead, while burning. 

[DuneElliot]

On 8/3/2017 at 11:10 AM, Yarome said:

That's entirely your choice. One 10A in-line (panels to controller)... that means your only option is to run all 4 in a single series array.

Not if I put it between the MC4 connector and the lines to the charge controller, which is where I ended up putting it. Seems to be working just fine in that set-up so far...that may change, and if it does I will change the fuse.

[Yarome]

4 hours ago, DuneElliot said:

Not if I put it between the MC4 connector and the lines to the charge controller, which is where I ended up putting it. Seems to be working just fine in that set-up so far...that may change, and if it does I will change the fuse.

If you wired your 4 100watt panels in series.. you're correct. It's a non-issue.Which is what I said. If you wired in parallel or series/parallel... it may not be evident yet with overcast or minimal production, but it WILL kill your arrays.

[DuneElliot]

Why would a 10A fuse kill my array in S/P?

[DuneElliot]

Called Reongy to confirm fuse not needed nor would it invalidate the warranty on anything. 

Fuse removed...pain the a$$ since I'd used Eternabond to attach wires to the roof to keep them in place.

[reed and elaine]

Ran into a tree in Izamal, Yucatan with our 34' fifth wheel which pulled 215 W panel off. Fortunately, had electric drill, large bolts and goop glue and were able to fix the mount. Need to look at mounts on all six panels.

Drove 600 miles on gravel roads in Labrador in 19' Roadtrek and noted that there was fatigue on two mounts and replaced them. This winter we drove down from Oaxaca to the Isthmus of Tehuantapec which is world famous for winds. We got caught in 60 mph cross winds near Los Ventos (seven semis were rolled on one day there). 315 W panel tore loose due to failure of bolt attachment to the panel. This caused failure of another mount. Stuck the panel on back of Roadtrek with Gorilla Tape and tie-down straps. Spent the night at an all night Pemex trucker fuel station near Minatitlan. The Manager came out to make sure we were in a secure and well lighted spot. Solar is big in Mexico and he humorously inquired how well the panel worked at rear of vehicle. I told him it should work well going north but we were headed south to Yucatan. He laughed. Sewer system fell off next day. When it rains it pours.

Younger son and family came down to spend a week on beach. He brought down sewer hose. We had to dig a trench under the Roadtrek to work on this problem and cludged a fairly good fix that worked for next 8 weeks.

Had to go to Playa del Carmen to find extruded aluminum L-channel. Took a while to find an aluminum supply shop. We put 1" x 5' aluminum strapping on the tie-in flange of the solar panel to basically provide a very large "washer" to prevent bolts pulling out in future. A 5' long 1.5" (probably 4 cm) section of channel was then bolted to solar panel flange on each side. Two shorter sections of L-channel was bolted and silicon glued to Roadtrek roof (the roof curves from back to front). These were bolted to the 5' section on the panel. So we had cludged a nice Z-channel; however, such channel was not available. this is undoubtedly over-engineering but the panel should remain in place.

Reed and Elaine

[eddie1261]

What would be the mechanical reason for the one between the charge controller and the batteries? If the one from the panels to the charge controller blows, doesn't that break the whole circuit? Asking because I will be putting solar up in spring. Just one panel though, a 265 watt panel, so series vs parallel obviously won't be a thing for me.

[Lou Schneider]

8 hours ago, eddie1261 said:

What would be the mechanical reason for the one between the charge controller and the batteries? If the one from the panels to the charge controller blows, doesn't that break the whole circuit? Asking because I will be putting solar up in spring. Just one panel though, a 265 watt panel, so series vs parallel obviously won't be a thing for me.

If you get an internal short in the controller, you want a fuse between it and the batteries to disconnect the controller from the batteries.  Otherwise the batteries will backfeed into the short.

The reason you don't want to rely on the catastrophic fuse to protect the controller and it's wiring is the catastrophic fuse is sized to pass the full inverter current and the controller wires are usually much smaller than the inverter wires.  They need a separate fuse at the batteries that is appropriate for their size.

[Yarome]

On 8/8/2017 at 8:54 AM, DuneElliot said:

Why would a 10A fuse kill my array in S/P?

DuneElliot- Sorry! With this new forum format, if threads drop below 5 or 6 pages I generally don't see them. Reed's post popped it back up into view. ;-)

It sounds as if you have it resolved, but just for general knowledge. In series, voltage is addative while current is constant. In parallel, voltage is constant and current is addative.

Specifically for you.. if you are running S/P arrays your current output (amps) would exceed the 10amp fuse. In series.. you would be generating 48volts (4 x 100watt 12v panels) and ~8amps. A 10amp fuse would be appropriate. In S/P (2 x 100w x 2 arrays) you would be generating 24volts and ~16amps. It would pop your 10amp fuse. In parallel (4 x 100w x 4 arrays) you would be generating 12volts at ~32amps. Again... it would pop your 10amps fuse.