BoatBanter.com - Drone View of Cool Docking Maneuver

On 9/20/2015 1:08 PM, Justan Olphart wrote:
On 9/20/2015 1:13 PM, Mr. Luddite wrote:
On 9/20/2015 12:24 PM, Wayne.B wrote:
On Sun, 20 Sep 2015 12:09:42 -0400, wrote:

On Sun, 20 Sep 2015 09:13:03 -0400, Wayne.B
wrote:

On Sun, 20 Sep 2015 02:05:05 -0400, wrote:

On Sat, 19 Sep 2015 15:01:49 -0400, Keyser Söze
wrote:

I've been working my butt off the last few weeks, digging edging
trenches for my wife's endless "garden areas," trimming trees,
shaping
Nellie Hollies, spreading mulch, and this morning I dropped a dead
70'
tree behind the back yard and chainsawed it into 4' lengths I
could dump
in the woods for the woodpeckers.

I am cutting up an old orange tree this weekend.

===

I'm running in the wiring for a solar panel project on the trawer. The
goal is to have (8) 100 watt flexible panels on top of the flybridge
enclosure which will feed a MPPT charge controller in the engine room.
If it all turns out as planned we should be able to leave the boat at
anchor during the day without running the generator.

Sounds like the perfect application for solar. I like solar but I have
a hard time justifying it for most things. Although this orange tree
is not involved, most of this tear's tree trimming is to improve my
solar performance for the pool/spa collectors.

===

We have fairly reasonable electric rates here and also high
consumption, all of which makes it harder to justify solar electric
for your house. When panel prices become comparable with shingles,
that will be the time to seriously think about it.

It's just about ideal for boats however, especially now that the price
of panels has come way down and efficiency has gone up. Sailors have
been using wind generators for a long time but they are noisy and high
maintenance. There have also been some notable accidents where people
have come into contact with the spinning blades.

You guys have reminded me of a weird problem I had with one of the Class
C RV's we had. It was a Chinook Glacier and the problem was
compounded by how the charging systems was set up. It had dual
batteries, one for the engine and chassis electrical systems and
the other dedicated as a "house" battery for the camper/RV systems.
It also had an inverter/battery charger that ran when connected to
"shore power" and also had a solar panel charging system integrated
to the electrical controls. It was supposed to keep your batteries
on a "trickle" charge during daylight hours. To make the whole thing
more confusing, the RV also had one of those "smart" electronic battery
switches that automatically switched the charging systems to the battery
with the lowest voltage. With all that in mind, here's what happened:

Everything was fine for a while but then one day after the RV had sat
unused (and not connected to any external power source) for a couple of
weeks, I tried to start it only to find the main battery was dead.
Wouldn't turn over. The house battery seemed to be ok. Put a charger
on the main battery and got the RV running. Then, a week later it was
dead again. Thought I had a bad battery, although the RV was brand
new. I took it back to the dealer and they checked it all out.
Said there was nothing wrong ... the charging systems, including the
solar panel, were working fine.

Went home. Few days later the main battery is dead again. I got very
curious as to what was going on so I started troubleshooting. At one
point I put a multimeter in series with the main battery negative cable
to measure any unusual parasitic current flow other than that required
for the radio preset memory, etc. I noticed that the battery was
actually charging slightly .. due to the solar panel system. This also
meant that the house battery was higher in voltage than the engine
battery.

But then, as I monitored the meter and was thinking about it, a dark,
heavy cloud temporarily blocked the direct sunlight. The current flow
displayed on the meter *reversed*. Instead of charging, it was
discharging. When the cloud passed, the current flow reversed again and
it was charging. I watched this happen a few times as clouds passed by.
Then I got a tarp and covered the solar panel on the RV roof. Battery
immediately started discharging. Took the tarp off and the current flow
polarity reversed and it started charging.

Got the schematics for the solar panel charging system. Very basic
system. There was a diode in the circuit that only allows current flow
one way (charging). It's unusual, but it had failed in a shorted mode.
When this happens, the panel can act as a radiator as well ...
especially at night .. and discharges the battery energy off to the
black body of night space. Replaced the diode and all was well.

And you accomplished something that factory hands on support couldn't.
Youse a pretty smart fella.

I got lucky. The dealer techs were checking things outside during the
day in bright sunshine. All looks normal then. My clue was watching
the meter reading positive current flow, then decreasing as the cloud
starting blocking the sun and then going negative when it was well
blocked. Betcha at night it was very efficient.