12 volt wiring

[Gulfislander]

Hi All,
I just purchased a propane heater with an internal 12 volt fan. I have a bulkhead light close to the position I will mount the heater. Can I splice into the bulkhead light to get power for the fan?

[David M]

Although you might get away with it purely from an electrical load standpoint, that would not be a safe thing to do.

I would not put a heater fan and lights on the same circuit. I would run the additional wire necessary for the heater fan and heater controller keeping the lights off the same circuit. Breakers really should be used for powering loads that are similar in purpose. The bottom line is that you want to put the fan and the heater controller, which shuts down the solenoid valve for the fuel, on the same circuit so that the fuel shuts off and the fan stops if there is a problem...with one flick of the breaker..other than by the light from flames of the fire!

Could you imagine having a heater fire, shutting off the breaker for it and your cabin lights go out? How would you quickly find the fire extinguisher in the dark?

This is a bit lengthy but is is best to know this information if you are going to be doing your own marine electrical work.
BoatUS BoatTECH Guides: Choosing Cables & Terminals for Marine Service

[David M]

Correction:

Originally Posted by David M

Could you imagine having a heater fire, shutting off the breaker for it and your cabin lights go out? How would you quickly find the fire extinguisher in the dark?....other than by the light from flames of the fire!

[hellosailor]

If the propane heater JUST uses the DC power for a fan blower, AND there are other lights on other circuits, I wouldn't be terribly concerned about putting the fan (and fan only) on the lighting circuit, if the circuit was wired and fused properly.

But overall I'd agree with David in any case--I prefer each gizmo to be on a separate run, separate breaker, and when the inevitable problems happen, that way they only happen to one thing at a time.

But speaking of finding extinguishers in the dark--many hobby stores have "glow in the dark" tapes and paints, and a stripe of that on or around your extinguishers can be a very handy thing. (Bulkheads, companionways...all sorts of places can be handy to mark with it if you're often about in the dark.<G>)

[GordMay]

Originally Posted by hellosailor

... many hobby stores have "glow in the dark" tapes and paints, and a stripe of that on or around your extinguishers can be a very handy thing. (Bulkheads, companionways...all sorts of places can be handy to mark with it if you're often about in the dark.<G>)

There’s two types of "glow-in-the-dark" tapes

Photoluminescent Tapes are energized by a photo-luminescent mineral (often strontium oxide aluminate) that is non-toxic & non-radioactive, and work on the principle of light-absorption, and re-radiation. Any type of light will charge the tape, but sunlight, halogen, xenon, & fluorescent lights work best.

There a number of different types of Retro-Reflective Tapes (Glint Tapes) with varying degrees of reflective quality. Most Glint Tapes reflect only visible light, as they are very dark in tone / color. Others are IR (infrared) retro-reflective only, and usually look like black duct tape. The best types reflects BOTH Visible and IR light

[hellosailor]

Gord, in the states we only call the photoluminescent tapes "glow in the dark". The reflective tapes not luminescent in any way, they are referred to as "reflective" because they don't "glow" in any way, they only reflect other light. Albeit they do it damn well. The brand name most common is "3M ScotchLite" since 3M is the market leader for that material. It is (or at least was) a mixture of glass beads finely coated on the substrate. They used to make that as a paint, but if that's still on the market 3M no longer makes it. (Someone must make it, it is silkscreened onto work vests and the like in a silvery color.)

Then of course there are tritium capsules, radioluminescent, which glow from radioactive decay. Those are used in some exit signs, airport runway markers, and other critical applications. In small amounts, on watch dials and in gunsights, too. But those are way more expensive, and too dangerous (toxic if opened) for the home market. There are also international import/export laws about those, since it is a radioactive material. There are still radium watch dials out there as well--where the "glow" on the dial and hands is form radium-based paint. I think that was banned in the 20's or 30's, but the watches are still out there. And the plant that made most of the paint was only recently (in the late 80's) cleaned up as an EPA "Superfund" site. It is now the unsuspecting home of a health club.

I wonder if "Glint Tape" is someone's Canadian trademark, like 3M's Scotchlite is a mark? I've never heard the term in the US.

[David M]

SOLAS, (Safety of Life at Sea) approved reflective tape intended for life jackets and other emergency gear is great stuff. I bought some for increasing the reflectiveness of some work vests we have onboard for night time use. You can buy it in rolls. I put some on my bicycle for riding at night. This stuff is pretty darn bright compared to other reflective tapes.

International Convention for the Safety of Life at Sea