Tuesday, July 17, 2007

How A Simple Job Becomes Three Days of Torture

A simple job: Install a Xantrex Freedom 20 inverter/charger and Link 2000 monitor. Stated in a sentence of a few words. A couple of hours, done deal, right? Maybe a day.

"But wait," you say, "Nothing takes a few hours on a boat." And you'd be right.

First, one must have a vision of what one wants to do. So here's the vision:

  • Take the 2 - 4D batteries and the 8D and make them one bank.
  • Add a Group 29 battery as the starter/emergency bank
  • Install the Xantrex Freedom 20 inverter/charger
  • Install the Xantrex Link 2000 monitor/remote control (for the inverter)

The first issue was to figure out the current wiring. Because the battery switch decidedly did not turn off power to the boat it became a priority to fix that. The next was to figure out the best way of wiring the batteries so that the banks were appropriate and measure for the new battery. Finally, because the old battery charger was seen as a 120 AC load off the panel rather than being in the circuit from the shore power, remove the wiring and insert the inverter/charger in its place.

The nice thing about the Xantrex Freedom 20 is that when shore power is applied it acts like a charger with all sorts of fancy functions. When off shore power, it can provide power to all the 120vac outlets through the inverter. It has automatic switchover, so you never have to worry. But it is also controllable in the event you don't want to charge your batteries or run the inverter. It also has an echo charger for the second battery bank.

The Link 2000 is the remote control for the Freedom 20, and it does all sorts of monitoring for two battery banks.

Jack Rabbit Marine provides a kit with all the stuff you need to do the job except incidentals like wire and connectors. Fortunately, there's Bridge Marine on City Island who supply pretty much everything at really good prices. Like Defenders and West Marine used to be. Moreover, they're nice and knowledgeable.

By Friday evening, I figured out where everything was going to go, how I was going to route wires and cables, and had cut a hole in the panel above the nav station to install the Link 2000. I also had removed the old Datamarine log meter that was non-functional. Unfortunately, that leaves a 4" hole in the panel. I'll deal with that later.

One of the problems of a 30 year old boat is that over the years people add stuff. And to put it delicately, they are not always so careful about how they do it. Wires are strapped to other wires or run in the easiest manner even if it doesn't make sense particularly. We all do it - how often have you said after completing a job, "Ah, I'll straighten that all up later. It's cocktail hour." Somehow, later never comes. I was/am determined not to fall in that trap too far.

Saturday I spent removing old cables that weren't needed, for example the 120 VAC line to the battery charger, the two separate sets of cables from the original 4D batteries (one each positive and negative), and one ground cable of the two to the engine. Fortunately, some could be re-routed to be used again for something else. Also, I found that the newer battery (the 8D ) was wired directly to the 'Common' of the battery switch meaning 12v power could never be turned off.

After a trip to Bridge Marine and some $200 later, with 25 feet each of red and black 1/0 cable (big wire), a mess of crimp on ends, and a few other little items, I was ready to install the new starter battery and run its cables over to the hanging locker that doubles as a wiring closet (or is it the other way around?) I also removed the battery charger so I could install the Freedom 2000 in its place.

What's amazing is the new gear is lighter than the old and does much more! Pretty cool. And there are lights on it. What could be better? Maybe some knobs. They don't really have to do anything, but should go all the way to 11. But I digress.

By Saturday evening, the following had been accomplished:
  • Mounted buss bars for ground, battery bank 1 positive, and ships switched positive
  • Mounted the Link 2000
  • Rewired battery bank 1 so that the positive to positive to buss bar and negative to negative to ground buss bar from opposite batteries
  • Added the former battery bank 2 8D battery to battery bank 1
  • Added and ran wires from the new starting battery (now bank 2) to the wiring closet
I'd say that half the time spent was tracing and removing old, unnecessary wires. Nothing is worse in boat electrics than pawing through unused wires from equipment that no longer exists to find a connection. Ok, rebuilding a head is worse, but you get my point. A serious waste of time.

Since I was running my portable refrigerator, I had to keep at least one battery hooked up, or if none, only for a short time. It is important to keep the wine and cheese at the appropriate temperature...

Sunday was spent wiring the Link 2000 monitor/remote control into the system. It sounds simple in that there's only like 8 wires, but I had to mount a terminal block behind the electrical panel, run the extension cable to the shunt, and then two wires back across the boat to the third battery. All very easy, all very time consuming.

The final task was to replace the 120VAC line from the deck socket to the Freedom 20, and thence from there to the AC main breaker in the power panel. Remember, the Freedom inverter/charger auto switches the ship's AC from inverter to shore and back.

I was going to provide the before and after wiring diagram, but it's too big a pain. Why would you want to know the wrong way to do it? Here is the final wiring. A final note - the current gel batteries were old, in two cases, from the mid '90's. So I replaced them with three 4D AGM batteries. It turns out that the solar panel controller was never providing the proper voltage for charging, so during the day it was running the 'fridge, but never adding to the power available.

With the new batteries I have 600 amp hours to fool with. Just so you know, an 8D battery weighs 160 lbs. A 4D battery a mere 120 lbs. I found out I could still lift and carry them! But still, I rigged up a block and tackle to get them off the boat at the end of the main boom. No sense doing something stupid...

Now I can get out - and I'll see you on the water.

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