Here we are. Simple ‘mounted on top of a truck’ box. Finally got together enough parts to plug it all in.
Basics (to date)
flexible 100w panel
renology li 30A charge controller - it’s cheap and MMPT and handles lithium for future expansion.
old marine deep cycle battery that’s been sitting in the garage.
used ammo can.
Tested it all, looks like there’s charging.
Next couple steps -
getting in passthrough fittings to get wires into the ammo box, and from the camper shell roof into the shell itself.
getting a 12vdc plug to mount on the ammo can (combi charge state + USB + 12v out marine fitting is on order)
mounting everything.
Putting in some parallel plugs so I can toss on a second panel as needed (I have a portable folding 100w that’s perfect for that sort of use case)
You need to make sure it’s vented. That battery will offgas if charged properly.
Most batteries emit some acid splash/mist as well. You might want to mount the charge controller on the outside of the box, they can corrode up in a hurry.
It should work fine!
What gauge/insulation rating PV wire do you have on it? If it’s 12AWG/600V, I’ve got some glands that will fit it I can toss your way, otherwise you’ll have to order some. Be aware that 12AWG/600V is 5mm, 12AWG/1000V is 6mm, 10AWG/1000V is about 8mm. This is hard to find.
Andersons are awesome for adding panels, just don’t make/break under load. You probably won’t get a DC arc fault at the low voltages you’re running, but… still.
Nice setup, clean install. Agree with @Syonyk that the cross bars are going to kill its efficiency. Those flexible panels aren’t very great to being with, but they’re damned handy and a lot better than nothing, plus they’re more durable in a beat-it-up situation.
What are you using it for, ham radio gear? I had a nice Kenwood mobile (with APRS) set up in mine, remote display, cab-mounted remote mic. Had the antenna professionally mounted to the roof by a company that did the local police and fire vehicle installs. Due to the excellent ground plane of the roof, reception and transmission quality were consistently phenomenal.
Depending on how the panel is wired internally, that’s easily enough to drop the output down to 10% of rated or so. Good shading like that will more or less shut down current flow through a section of panel, relying on the bypass diodes to let the other sections flow. If you block two, well… it depends on how thing are wired, then.
Try it and see, but I would be very surprised if the controller can extract more than a tiny fraction of rated with that shading.
I’m interested to hear how they handle partial shading. Like many people i’ve seen this youtube vid, i haven’t heard of many people actually repeating this experiment for themselves i’m curious if the 90% drop in output Syonyk predicted is accurate or if its less extreme
Will need to run some tests still (and to get the BT module to pull data out of the charge controller) - but the panel is the ‘shingle’ style design flexible ones. (mine’s a different OEM but same design)'s information page
Interesting, hadn’t seen that layout before. I’ll be interested in your results. Limited shading on my panels really tanks their output, but… I also don’t really care. They’re in basically full sun, except for very early sunrise on the west A-frame and sunset on the east A-frame.
There exist some panels that are split top/bottom (instead of in three “vertical” stripes with the panels in portrait orientation), and that would gain me a tiny bit on my home array, but not enough to justify the cost delta for them over what I got.
I would still expect your bars to have a significant impact on output, but I could be entirely wrong!
Looks like about 30-40w peak, today was a whopping 2w heh. (very overcast today).
So ‘as expected’ based on mounts and weather. It’s truck top, it’s gonna get shaded, and it’s not angled right at the sun so the ‘best performance’ is gonna be at noon near the summer, otherwise it’s an angled panel.
Enough to charge the battery and run lights and radio, and the second connector should help if I’m parked somewhere and want to put up a second panel that’s a little more optimized for conditions.
Just recalled I had a handy lumen meter. (oh my phone, DUH)
Ambient light outside today was about 350 lux, so 350 * .0079 (conversion to w/m2) * .6 gave it a hypothetical 1.6w of sunlight to work with. (it’s pretty wet today).
