Headed home soon

There are still a lot of things left to do on the boat, but we’re almost done with the things the insurance company needed us to do. It’s not been for lack of trying to get them done, stuff just takes time.

The most recent task completed was replacing the batteries in Opus. Previously, she had lead-acid batteries. They are fine for many things, but they do require maintenance – refilling with distilled water and they aren’t sealed. This means that the could tip over and spill acid in the boat, which is bad. Even worse is that they can offgas during charging and that gas is a combination of oxygen and hydrogen. You know, the stuff that caused the Hindenburg to burn? It’s combustible with the slightest of sparks.

So we replaced them with three “AGM” batteries. This had several advantages. The first is that one of the old batteries was going bad and would soon need to be replaced. We could have replaced it with another lead acid battery, but those are “old technology”. You shouldn’t mix lead acid with AGM batteries because of differences in how they like to discharge and charge. Before I go any further, I should explain how the batteries on Opus are set up.

There are three batteries. Two of them are hooked together to act like one. These are “deep discharge” batteries, aka “house” batteries. They aren’t intended to output a lot of power in short bursts. They are the “slow and steady” batteries that take a long time (relatively speaking) to discharge and are used for most of the electrical stuff in the boat such as lighting, the solenoid for the propane system, the radios, the chart plotter, etc. The third battery is the “starter”. It is used to run the starter motor for the engine. It has to output a lot of power, but only for a short time (10 seconds or so).

The starter battery is like a sprinter, the house batteries are like marathoners.

And that’s why we couldn’t do something smart like put in an AGM battery for the starter battery and move the old starter battery to replace the house battery that was going bad. Further, our battery charger doesn’t have one setting for the starter battery and another setting for the house batteries. It wants them all to be the same type.

So we decided to replace all three batteries with AGM batteries, which are sealed batteries. No maintenance to speak of. They had the further advantage of larger capacity, so we can go longer between having to charge them up (though it then takes longer to charge them again, too. Nothing is free).

You would think that this would be an easy matter. Disconnect the old batteries, pull them out, put the new batteries into the battery cabinet, reconnect the cables, and voila! Done. Nothing is ever that simple on a boat.

How many cables do you think goes to the batteries? It would make sense that there would be one for the positive terminal and one for the negative terminal, right? multiply that by three batteries and you’d expect a maximum of 6 cables. Further, the “rules’ say that one cable is red (the cables that go to the positive terminal) and one cable is black (the ones that go to the negative terminal). How difficult can this be?

Except… there are 10 cables in there. 3 of them are red, the rest are black, which makes no sense because I know all 3 red cables go to the house batteries. Where are the red cables for the starter batteries? (if you’re curious, the 3 red cables that go to the house batteries are one cable from the charger to the battery, one cable from the battery to the rest of the boat, and the third one is used to tie the two batteries together to make them act like one, larger, battery. The same is done for three of the black wires). Ok, the house batteries are hooked in, but why are all the starter battery cables black? At least ONE of them has to be going to the positive terminal or else the starter won’t work.

We eventually were able to determine what was the function of 3 of the black cables. Two of them were, indeed, SUPPOSED to be red. Another, was definitely supposed to be black. That left us the fourth wire and we couldn’t figure it out. So, we made the assumption that it also was supposed to be black. However, not being complete dimwits, we turned off every bit of power in the boat, disconnected shore power, turned off all the switches, and then connected the cable. Nothing bad happened, so that was promising.

One person positioned themselves next to the batteries and the other person went to the control panel and turned the switch to the “1” position (which connects ONLY the engine battery). Almost immediately I heard “OFF! OFF! OFF!” Yes, I was the dummy at the control panel and I turned it off immediately.

We had guessed wrong. the last wire was ALSO supposed to be red.

So the configuration for the house batteries makes complete sense. 2 red cables plus the jumper cable on the red terminals of the house batteries, ditto for black on the house batteries. The starter battery is ONE cable on the negative terminal and THREE cables on the positive terminal. Those three are SUPPOSED to have red markings on them, but all four are dark black.

Oh, why was he yelling OFF OFF? He could hear the sizzling as the short started to fry insulation and wiring. Fortunately, we were fast enough to prevent anything truly bad from happening. If I had been by myself, it would have been a lot, lot, worse. The sequence would have been connect up the wire, walk through the doorway to the nav station, turn the switch on, run back to the battery, hear the sizzling, run back to the nav station, turn the switch off. By that time, there’s a good chance we would have had an electrical fire on board.

Fortunately, the batteries are all sorted out. We have boots on order to cover the terminals so that they can’t be shorted as well as strapping so that they can’t move around on a pitching boat.

The only other real job to do for the insurance company is one that I’m still waiting for the proper parts for. I understand it’s on back-order, so after a bit over a month of living on Opus, I think it’s time to go home this week for a month.

Opus may be the new lady in my life, but I really miss the important lady who’s been keeping the home together. It will be good to see her.

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