23 electrical question

[brackish]

On my cruise last week, my anchor light did not work, kicked the breaker when I tried to turn it on.

Preliminarily, I've found this.  The masthead fixture seems to be good.  with a good bulb I get continuity from one side to the other and with the bulb out, none.  I also get continuity from one pole in the fixture to the mast and that doesn't sound right.  Fixture itself seems to be properly insulated from the mast, it is all composite.

On the other end I have a four pin connector, masthead anchor, steaming, deck, and common.  I'm assuming the one large pin is the common.  I get continuity between each of the small pins and the large pin.  I also get continuity between the large pin and the mast and that doesn't sound right.

Is there an open in the common somewhere inside the mast?

Had I been thinking clearly last week I would have tried  the other fixtures to see if they pop the breakers which would indicate a common problem, but I didn't.  Maybe I should check each fixture to see if the common open is at one of them rather than somewhere inside the mast?

Have I overlooked something before I pull the in mast wiring harness and start over.  Electrical is not one of my strong suits and I hate the thought of that.

Compac's wiring diagram is less than helpful, they only indicate one light on the mast.

Second question has to do with quieting the "slap" from the in mast wiring.  Pretty loud at anchor with a chop.  What have you used?  I've heard of encasing it in pipe insulation and someone said you can tie wire ties about every three feet and leave the tail uncut and that will stop it.

[Bob Condon]

A few things to check out.

I believe that you wiring in the mast (3 small pins, 1 large pin) should be:

each small pin is the + side of each light bulb

The large pin is the return or - side of the lightbulb

I would expect to see conductivity from the large pin to one side of each light. The bigger pin
is because you could theoretically be combining the current of all three lights at one time.

================

Things you can check:

I assume you have a deck plug for these connections.... unplug them.

> Now with power off, check conductivity from the large pin back to the battery negative side.
[There should be conductivity]
> Just curious, is there conductivity between your mast and the battery negative side. [from what you said,
this should be true]

You will do this three times but once for ach light (steaming, deck and Masthead)

1. turn on power to the steaming light. With Voltmeter set to 20V DC, I use a wire with 2 aligator clips (from radio Shack)
clip on wire end to the deck side of the large pin (not the mast side)  to the black voltmeter wire and then use the red
volt meter and touch to each of the three small pin until you see power. I then make a diagram so I know which
pin/socket is for each light.

If you don't see any power on any pin, then the problem is in the boat side and not the mast side of the socket.


====

As for that pesky wire noise banging against the inside of the mast..
The best solution I saw is to buy a couple of sponges that you wash your car wit, but in in half and
then make the side just larger than the mast openning.

Slid one from the masthead top about 1/2 way between the mast head and the steaming light using a long pole
and then a second one from the mast base about 1/2 to the steaming light ...don't try to go past the steaming light because you may rip the wires off

[brackish]

Thanks, Bob, I think I found the problem.  When the masthead 360 fixture was installed the screw that holds it to the masthead casting also touches the - return side of the bulb holder. That shouldn't be should it? It then is screwed through the composite base and into the mast.  That is why I would get continuity between both the large pin and the - return side of the bulb holder to the mast or any conductive material attached to the mast.  Looks like they drilled holes for the attachment and got the screw too close.  I ground down the screw head and put a piece of tape between the bulb holder and the screw.  No more continuity to the mast.

Will test tonight by putting 12V to each pin and the common, see if each of the lights come on independently.  I will at least have eliminated everything from the mast male connector up if they all work.

[Bob Condon]

do not put 12V to the common pin. it should be a dead short to the battery!

[brackish]

Yep, I said that wrong, just got finished with the test, jumper on the common to the negative terminal, jumper from the positive to the three remaining pins, all systems go, made a diagram of what goes to where, thanks.