Travels With Miranda

I’ve been holding steady here these last few grey days, never going below 87% battery capacity. I’ve only used the alternator to get a voltage boost during the day for office-related matters, with the 10A or so I’d get out of it being a nice bonus. The solar has performed beyond all expectations, sucking an average of 4 to 5A out of the swirling dark grey mass above us.

Last night, the battery monitor claimed that I was at about 93% and down 16.8A. Guess what all my volt metres were telling me? That even with the fridge and a light going, I was between. 12.58 and 12.61V. Which meant that with everything off, I’d be above 12.6V, which is considered a full charge.

But I knew better because my amp meter is calibrated properly. Without the battery monitor, I would have gone to bed smug and pleased that I got to a full charge last night and would have just run them down today as though I was starting over.

Imagine if I kept doing that over the lifetime of my batteries, just getting them near, but never at, full charge. That would eventually kill them. With the battery monitor, I know that they need just a little more charging them.

Voltage readings do matter and have a use; I’ll be doing up a post about that. But I don’t know how anyone can do any serious amount of time off the grid without a battery monitor because they really are the only way to know exactly where you stand.

Today is another day with more sun than expected. It’s chilly, but I’m not complaining!

I’m going to have the computer on charge all day since I’m in major backup mode. My MacBook Pro keeps crashing, so complete hard drive failure is imminent. I just need to decide on a new drive and order it; the choices are a little overwhelming. I want to make sure I have several recent Time Machine backups and two different bootable backups. It’s likely way more than I need, but with the current drive being only good for the dump, I want all the chances I can get to be up and running perfectly about four hours from the new drive making it here.

Power right now is at 88% and holding. I’m actually getting 7 to 8A in, so I’m breaking even. The more the batteries are depleted, the more efficiently the alternator charges them, so I’ll wait till about 4PM and then run the engine for a bit to make sure I’m at at least 90% capacity tonight and then I’ll aim for 100% tomorrow.

In other news, R and S from Colorado are back, so a beach party is imminent!

The twist being that I have solved yet another mystery. Everything is FINE. Perfect even!!!

For days now, I’ve been experiencing gigantic voltage drops in the evening. Tonight, with everything off, I was at about 12.5V. Turn on the fridge and I dropped to 11.9V. Turn on an LED light? Forget it. The voltage drop wasn’t just in the rig, I was experiencing it right at the battery. Something was very, very wrong.

So I haven’t been using any power in the evening except an LED light for just a few minutes at bedtime because I was sure my electrical system or batteries or both were on the verge of going KABOOM.

I didn’t want to put any of this on the blog because I feel that many of you have given me way too many braincells already. I had all the information any outsider could give me. It was time to do the hard work myself and until I either solved this issue or came up with a specific gravity number for my batteries, I was staying mum.

Just before dark this evening, I took some voltage readings. Could my solar array monitor be wrong? It was wildly fluctuating.

I headed outside in the waning light to take a gander at my battery bank. Or, rather, I felt around with my hands. My connections were all tight. I pulled out my flashlight and… wait a minute. Was that corrosion on the positive terminal?

And that was the missing variable, folks. We’ve all been looking at my battery issues as a textbook situation rather than in context. Where I am, context is important. I am by the ocean. I’m seeing rust form on all my exposed metal right now. So it’s obvious in hindsight that some of that salty air would end up on my batteries.

So I recleaned that terminal and then coated all my connections yet again in dielectric gel.

Now, voltage with everything off? 12.55. Fridge on? 12.48. One LED light on? 12.44. Two LED lights on? 12.4. All of the above plus the incandescent stove hood light? 12.38.

The icing on the cake is that my battery (still flashing 0.00V, mind you) is perfectly calibrated. I know I’ll have a full charge by lunch tomorrow and then I can start to plan a strategy for the couple of grey days ahead.

L has the tools and knowledge to remove my motorhome starting battery and test (and repair or replace) the solenoid, so I will try to wrangle him tomorrow afternoon to do that, and early enough to run into town to the auto parts store if we need to.

It’s been a really great day on the beach. Now, there’s a strawberry daiquiri in the freezer with my name on it!