Testing my anchor and mast lights while mast is down

Jackdaw · Dec 17, 2015

Find a donor 'wall wort' power supply from some old abandoned gizmo. See if its rated at +12v . If yes unplug, cut the tip off, and twist onto the wires where they come out of the mast.

This assumes you have AC power near the boat. If not. move the boats house battery, or wire a pocketful (8) of AAs together in series.

Anonymous 121765 · Dec 17, 2015

Four,

For me, it would depend on the type of connectors you have in your wiring.
If you have an electrical tester that has voltage, amps & OHMS, it's a simple test.

If having two wires, simply set the tester on Ohms (also known as continuity).
Attach the leads & wait to see that your reading shows three zeros. If so,
you have a complete circuit & the bulb is not bad.

If the reading numbers jump around, it may be a bad bulb or maybe a break in your wire or a connection problem.
If all else fails, take Jackdaw's lead pal.

CR

Jackdaw · Dec 17, 2015

captnron said:
Four,

For me, it would depend on the type of connectors you have in your wiring.
If you have an electrical tester that has voltage, amps & OHMS, it's a simple test.
If having two wires, simply set the tester on Ohms (also known as continuity).
Attach the leads & wait to see that your reading shows three zeros. If so,
you have a complete circuit & the bulb is not bad.

This is a solid idea, maybe better that a battery test if you have a multimeter AND incandescent bulbs. But you need to do it a little differently. Its because an incandescent bulb will have some internal resistance (its how it glows). First measure that amount (bulb tip to screw base) and then insert it. Then do the check with the wire. The number shoud be the same or close. Dashes (---) mean you have problems.

With LEDs its more complex. Typically measured in one direction that will read open circuit (---) because it is a diode. Changing the polarity of the test by turning the leads around will result in a different reading. That number will vary depending on who made the bulb.

Always best to test LEDs by powering them up.

justsomeguy · Dec 17, 2015

fourwhitesocks said:
PS they are not LEDS although I guess they should be...

That'll make the continuity tests even easier, I think, as per Jackdaw's comment.

Jackdaw · Dec 17, 2015

fourwhitesocks said:
Oh ok so I can use a volt meter? I do have one of those...just hook it to the wires at bottom of the mast then?

Sorry I'm not an electrical gal at all, I'm better at filling holes with epoxy lol

PS they are not LEDS although I guess they should be...

Find the two wires you think are to the light fixture. Attach the leads of the volt meter solidly to them.
Set the meter to OHMS
Take out the bulb
Text with the meter. It should read --- or INFINITY. If it does not you have the wrong wires.
Insert the bulb
Test again. It should read close to what you read on that bulb test, maybe 10-200 ohms.
If it does the bulb and wire are OK.

Daveinet · Dec 17, 2015

In addition to Jackdaw's comment, if your bulbs are incandescent, (as opposed to LED), they will still light with a much lower voltage, except they will be dimmer. So even if you had a 6 volt adapter or anything in between, it should work. AC or DC will not matter either just for a test, although if its output is AC, I would not use anything greater than ~10 volts.

Johnb · Dec 17, 2015

If you are going to use a 12 V battery with any real capability to deliver a big current then wire something like a automobile headlight lamp in series with it. It will still deliver all the current you need to make things work but if you connect stuff wrong it won't evaporate your wires.
If you connect up and it comes on full bright then disconnect promptly.

Daveinet · Dec 17, 2015

Most automotive parts stores have LED bulbs that are direct replacements - specifically AutoZone has a pretty good selection. Yes, you can get them cheaper online, but if you are only replacing a couple of bulbs, the local parts store is more convenient.

Brian S · Dec 17, 2015

Socks, you can get LED bulbs from the store here at Sailboatowners: http://shop.sailboatowners.com/cu/detail-led.php marinebeam.com is also another well regarded source. You should know that putting LED bulbs in a fixture that was originally incandescent bulbs potentially opens you up legal liability issues. (Imagine a scenario involving a drunk boater hitting your boat and causing injury or loss of life, and the lawyers finding out you had replaced incandescents with LEDs, and the drunk boater is free on a technicality. Not saying it will happen like that, but it could.) Anyway, to avoid that, replacing fixtures with new USCG LED fixtures, say from Hella or Aquasignal, avoids those potential problems.

As for wall warts, any A/C plugin adaptor for a device is known as a wall wart. Many electronic/electrical devices with a block that plugs into the wall outputs 12VDC. You need to check that the wall wart does indeed output 12VDC, rather than 14 or whatever. For checking an incandescent bulb, 14V is probably ok for a short time.

Daveinet · Dec 17, 2015

I think one would be hard pressed to prove negligence for switching to DOT approved replacement bulbs. Good LEDs are much brighter than incandescent. Used to be that the bulbs were not all that good, but any more, the bulbs are very bright.

Brian D · Dec 17, 2015

Before putting my steaming light back on the mast, I used a 9vdc battery to test the 12vdc bulb. Works just fine. However, it might not be as bright if testing from the mast base due to the length of the wire in the mast. But your bulb should at least glow if everything is good.