Today, Olivia and I “watched” a golf tournament and a Cubs baseball game all in cloudy weather on our covered front porch, all from solar and battery power. I guess that makes us officially off-gridders — at least for an afternoon.
The meter on the Renogy charge controller never dipped below 75% the whole time despite expectations to the contrary. Yes, this portable Sony Bravia TV is not drawing much wattage compared to a toaster oven. But at least that means three solar panels can adequately service a Sunday’s worth of football games even on a cloudy Portland day. And, I have a fourth solar panel arriving on Monday.
This test was perhaps the most stressful to date for the RETROvan. None of these components are made by the same company or guaranteed to work together other than in theory. The installation manuals for both the Renogy solar charger/controller and the ProMariner inverter/charger/transfer switch are negligently omissive. Neither product explains any interconnection steps or even acknowledges the fact that people might want to combine solar with shore power. And really now, who wouldn’t?
The other challenge is that the cable sizing, stripping, terminating and wrangling will drive even professional electricians crazy. In part because what’s in the manuals will not match what the companies tell you in person, nor what’s on the reference charts. That may be because everyone is so concerned about erring on the safe side, they keep compounding the problem. The cables between the inverter and battery bank are 2/0 AWG, which are nearly 3/4″ thick. And that just seems excessive to me, not to mention difficult to bend. The cables between the solar charger/controller and the batteries are 8 AWG, and the terminals on the Renogy component are terrible. You can’t really just screw them down and walk away, because as soon as the box moves, all of those connections come loose whether you’ve screwed down the bare stranded wires or terminated them in ferrules or butt connectors. Also, I had to search for a stripper that would even come close to handling 8 AWG cable, because every retail tool tops out at 10 AWG.I finally found a nice Klein Katapult device at Home Depot that cuts and strips individual conductors in a single step, up to 8 or 10 AWG depending on whether the wire is solid or stranded. But that’s still after taking five minutes to remove the outer sheathing with a box cutter. If you’ve ever wondered why electricians are so expensive, the menial labor is why.
So, while this test was successful I’m less than 100% confident in my cable choices and terminations for a permanent installation despite getting recommendations from both companies. Every vendor recommends hiring a professional electrician to cover their butts, yet they sell these components through retail channels like Amazon and West Marine without any hesitation. That’s similar to how the big pharmaceutical companies run TV ads urging ordinary mortals to use their dangerous prescription drugs.
The scariest part was when I went to secure the final battery positive connection from a stacked combination of my fused inverter cable (2/0 AWG), the solar charger/controller’s temperature sensor, and its 8 AWG positive battery cable. The post sparked like hell as soon as I touched it, so I stopped and went to get my neoprene gloves knowing that I would have to secure these three connectors to that post by hand and with a metal wrench.
I tried to research this sparking problem online because the ProMariner manual doesn’t mention anything about this in the installation steps. But of course, it’s Saturday and no one is answering the phone at ProMariner headquarters. Not impressed about that, since someone could get killed installing their product the day before Father’s Day while they’re offline. What if there were combustable gasses in the air? The device claims to be “ignition safe,” yet here we have a massive spark on first contact that could have brought the Hindenburg down?
But… when I finally worked up the nerve to try again — no spark. This suggests I had experienced some kind of static build-up charge that dissipated after that initial contact. But still, to have no connection instructions or warnings in the manual for an $800, high-powered device that could kill you in a heartbeat?! Really? Yes, a trained electrician should be doing this job, but what if he didn’t expect that little zap to happen either? Seriously, electricians are like surgeons. Even the best of them will get caught off-guard. I’ve seen it happen.
By around 7 PM, the inverter felt warm but the batteries and all cables felt the same as the ambient temperature. So that’s all good.