Travels of a Rambling Van: It Was Bound To Happen

It's a truism that when you work on something to fix one problem, another, sometimes related, sometimes not, will often pop up.

That was the case when I was tracking down the DC - DC charging issue I was having with the teardrop.

At one point I had my battery monitoring app open on my phone and noticed that when I closed the hatch, where the solar panel is mounted, the charge current from the panel dropped to zero, the voltage dropped to 13.2 (just below the battery voltage and likely cross-over through the charge controller from the battery), and the solar charge controller turned off.

Maybe a wiring issue? Because I was operating the hatch at the time, the wires between panel and charger had to flex and maybe they were failing at that point.

Anyway, a problem for another day.

Except that the next day, no matter how much I abused the hatch, I could not replicate the problem.

Oh well, just another one of those glitches the universe likes to throw at us once in a while.

Except when I went back on the 23rd and checked the charge controller's 30 day history I saw that charging stopped short of full between the 11th and 15th (the bright part of the bar-graft is bulk charging - take all the current the panel will give until the battery hits 14 volts - and the dim part is float - hold a maintenence voltage of about 13.47 - . In between is a short period of absorption - hold a voltage of 14.2 for a maximum of 2 hours, less if the battery wasn't discharged all that much overnight.) then there were several days where I got absolutely nothing out of the panel. Which only happens if I put a blanket over the panel. Even on the cloudiest of days I'll get something out of it.

Then it suddenly started working again on the 19th all on it's own.

So I started keeping a closer eye on things and consistantly found the panel not producing when it should have been. And it quickly got worse to the point when it never produced at all.

The options here are limited.

A wiring problem? Well I have three seperate inputs to the charge controller, three seperate sets of wires I can plug the panel into. Nope, unless all three sets of wiring failed at the same time, that wasn't it.

A charge controller issue? Not very likely, but since I have a spare controller on the shelf that's an easy thing to check.

Original controller, rated for 75 volts and 15 amps (input from the solar panels), on the left. Spare unit, rated for 100 volts and 20 amps on the right.

In fact, if I ever paired the 140 watt mounted panel with a 100 watt portable the combined output would be getting awfully close to that 15 amp limit in strong sun, so I'd be more comfortable with the larger, 20 amp, controller anyway.

Same input and output wiring. Just have to make a paper template to mark for new mounting holes back there where I can't see,

add a safety ground for that big finned heatsink (the ground is that white wire on the left side. The smaller controller's heatsink is a flat aluminum plate covered by the blue case so no safety ground needed), and we're good to go.

But as expected, this did not solve the main issue, just made the system a little more robust, but only if I could get it working again.

And to that end, there's only one thing left in the system.

Compared to some things we depend on, solar panels are remarkably reliable devices, even though they are left out in the elements around the clock and pretty much ignored for years at a time. In fact new data indicates that panels are consistently lasting longer than we expected. Many manufacturers offer 25 year performance warranties, but now it appears that 30, 40, even 50 year old panels reliably perform at 75, even up to 90% of their original rating. (70% is often concidered the threshold for replacement.)

But they are man-made devices subject to failures other than performance degradation, such as material failures and workmanship glitches, so they usually also come with product warrenties - for defects and such - usually for 10 - 15 years.

I have had well over a dozen solar panels over the past 3+ decades, eight of which I still use (the rest have been sold on with various RV's), all of them in mobile installations subject to the added stresses of motion and vibration. And up until now I haven't had a lick of trouble out of any of them. - Yeah, up to now -

Of course, the only way to know for sure that this is my problem is to plug another, known working panel onto the teardrop.

I've been threatening to buy a portfolio style

portable panel that I can use to keep the Jackery topped up with when the Ranger is parked for several days while I'm camping. (The fridge lives in the Ranger at night and runs off the Jackery.)

This seemed like an un-impeachable excuse to go ahead and do just that. And even if it wasn't, $90 for 100 watts of solar plus a handfull of wiring adapters is hardly worth impeachment proceedings!

And yep - a couple days later Amazon handed off this portable unit up at the gate (We have a big deck-box up there for packages since we do a lot of online shopping to avoid having to mingle with people. Sometimes I feel bad for the postman because out here Amazon drops everything off at the local post office and makes them do the last leg of the delivery. ) and it took all of 5 minutes to walk the 800 feet back down the hill to where the teardrop is parked, open the package, sort out the right addapter, and prove that the teardrop's panel is in fact the issue.

It, the teardrop's panel, produces the expected 26 volts when open circuited (not plugged into anything) but as soon as it is asked to produce the current that voltage should be driving it shits a brick and sits there even less useful than an actual brick - which could be used to prop a door open, keep papers from flying away, or smash a window - or even a head - if one was so inclined.

Not that I could do anything to fix it, but I did some experimenting and monitoring and decided the likely issue was a failed cell or connection between cells that could support a little current-flow (less than 0.2 amps) if it was cool enough (somewhere below 60) but heat it up or try to get more current out of it and something inside there opens up. Stop trying to get current out of it (open circuit), at any temperature, and it will produce 26 useless volts again.

Which, by anybodies definition is a dead solar panel. Well what the hell are you suposed to do with one of those?! (Contrary to oil company propaganda of a couple three decades ago, solar panels are not toxic. They are predominately made of highly recyclable materials such as aluminum, glass, copper, and a bit of silicon.)

But this is one expensive panel! Assuming one could even get their hands on it (notice the sold out notice).

Yes, it's still under product warranty but - even assuming the Canadian manufacturer has a few on the shelf somewhere that they aren't selling (because you don't fix solar panels. You scrap them and get a new one.), I still have to pay international shipping and customs fees, both ways, as well as a "testing" fee. And who knows how long all this would take and I have a trip coming up shortly!

Lightleaf is a great panel. 140 watts, built in kickstands and quick-release mounts for removing it from the teardrop and setting out in a sunny spot,

all on a tough carbon-fiber substrate formed to the same curve as the teardrop's hatch, with the whole thing weighing in at about 5 pounds, but for $109 dollars, less than the fee's neccessary to warranty-replace the Lightleaf,

I could get one of these Renology 100 watt flexible panels (I've already got 4 of these on top of the cargo trailer) and have it in my hands in two days!

True, 100 watts isn't the original 140, but I don't use all that much power anyway and if neccessary I can just plug in the portable panel for an extra boost.

The Renology has 6 of these handy grommets that I used to mount the panel, this time on the fixed roof just forward of the vent-fan which gives it better orientation for ray-gathering than the angled rear hatch. (Many buyers of Timberleaf - well, all, teardrops have roof-racks so this area is not always available for panel mounting)

After pre-drilling the surprisingly thick aluminum skin I cut a small tab of butyl sealant,

and tucked it over the hole

before driving each of the 6 stainless steel screws.

Being flexible the panel formed to the slight curve of the roof with no problem.

Using some half-inch wire loom, a few clamps, some tie-wraps, a couple of splices, and an SAE plug (to mate with the SAE socket already mounted on the teardrop - though you have to be carefull of the polarity when splicing these in because there's no fixed standard), all stuff I had laying around, I finished up the installation of my new - working - panel in about two hours.

But - in the photo above you can see 3 of the 6 mounting standoffs on the rear hatch for the original Lightleaf panel.

And frankly, useful and practical as they are, without a panel to hold they're kinda uggggly.

Each one of these is held down with two screws, leaving me with 12 holes in the hatch.

There's probably more eloquent ways of dealing with this, but using what I had on hand, the rubber-backed washers from some steel-roofing fasteners and some black-coated stainless steel pan-head screws,