In article , tdw wrote:

Harlan,
Given the relative youth of the boat have you spoken with J Boats themselves
? Just a thought.
I'm guessing here but I find it hard to believe the (presumably factory
fitted) wiring is to blame nor the main wiring panel. Maybe just really
crappy nav lights. Open one up and have a look inside.
Cheers
Andrew

"Harlan Lachman" wrote in message
...
In article , tdw wrote:

One thing that intrigues me however is that Harlan refers to his boat as
a
J100. Now I'm not being adamant about this but I was under the impression
that J100s have only been on the market a couple of years. If thats
correct

Boat has been available for only three years. Most boats have not seen
two full seasons.

I thought it strange too. Stranger still that I have never had
intermittent Nav light problems on any of my previous boats (power or
sail -- and none in this boat's price range :-(

harlan

--
To respond, obviously drop the "nospan"?

TPI makes their boats. I have talked to them. But as long as I cannot
assure them about what the problem actually is....

Harlan

--
To respond, obviously drop the "nospan"?

tdw wrote:
Regarding the halogen lamps undervoltage will not stop them working as
such but will greatly shorten lamp life.

I thought that too, as it would stop filament regeneration, but a
little research shows halogen lamps also have longer lives when
undervoltaged, as long as the voltage is above 35% of the nominal
voltage, or is periodically raised above that minimum. From a
manfacturer's website:

" Voltage: Reduced voltage produces a decrease in lumen output and an
increase lamp life."

" Dimming: Like all incandescents, tungsten halogen lamps can be
dimmed simply by lowering the voltage across the lamp. Full-range
dimming is relatively easy and low cost. The color temperature varies
over the dimming range, becoming warmer as lamps are dimmed. Dimming
generally extends lamp life, although the increased lamp life does not
follow standard incandescent lamp curves. As periodic high power
operation is required to raise a lamp's temperature up to the level
needed to activate the halogen cycle, continuous dimming below 35% is
not recommended."

In essence, yes cos what we know as halogen lamps are indeed filament lamps
which will have a longer lamplife if run slightly under voltage. If they are
constantly run below near full voltage they tend to blow early and also to
burn out the lampholder. if you test a lighting transformer you will find
that most run at about 11.5v not 12v. I'm not convinced by the 35% figure
but only because my own experience leads me to believe it's a bit high. I
would have thought it to be closer to 20% but I cannot back this up, it's
based purely on my own observation. The problem is all to do with the gases
inside the capsule not getting up to full operating temperature leaving
deposits on the filament. Running the lamp(s) at full power for a few
minutes avery now and then cures this problem but if e.g. final voltage to a
boat system drops below 10v one doesn't have the ability to raise
thistemporarily to 12v if the drop is caused by inadequate cabling and/or
connections. In reality of course the total wattage in a masthead nav light
is unlikely to be greater than 20w x 2 and thats a pretty low current. Even
a 1.5mm multistrand cable should be more than adequate over 10 - 15 metres.
cheers
Andrew
"Mark" wrote in message
ups.com...

tdw wrote:
Regarding the halogen lamps undervoltage will not stop them working as
such but will greatly shorten lamp life.

I thought that too, as it would stop filament regeneration, but a
little research shows halogen lamps also have longer lives when
undervoltaged, as long as the voltage is above 35% of the nominal
voltage, or is periodically raised above that minimum. From a
manfacturer's website:

" Voltage: Reduced voltage produces a decrease in lumen output and an
increase lamp life."

" Dimming: Like all incandescents, tungsten halogen lamps can be
dimmed simply by lowering the voltage across the lamp. Full-range
dimming is relatively easy and low cost. The color temperature varies
over the dimming range, becoming warmer as lamps are dimmed. Dimming
generally extends lamp life, although the increased lamp life does not
follow standard incandescent lamp curves. As periodic high power
operation is required to raise a lamp's temperature up to the level
needed to activate the halogen cycle, continuous dimming below 35% is
not recommended."

In article ,
Harlan Lachman wrote:

I hate the nav lights that came with my J/100. The days when they have
worked are less than 40% of the time I have tried to turn them on.

Does anyone have a fool proof plan for lights that work? Should I
replace mine with LEDs

I've been switching to LEDs and am extremely happy with them. You can
fix the wiring pretty easily as you're working. Quite likely, it's not
the wires but the socket, which you'll be getting rid of. You can even
replace the second most-usual problem, the quick disconnect. Solder and
shrink-wrap the connector, as the LEDs will likely outlive the boat.

--
Jere Lull
Xan-a-Deux ('73 Tanzer 28 #4 out of Tolchester, MD)
Xan's Pages: http://members.dca.net/jerelull/X-Main.html
Our BVI FAQs (290+ pics) http://homepage.mac.com/jerelull/BVI/