cheating with store bought light fixtures
 

Hey, thanks much for all the help recently. I want to replace the bare-bulb
interior bulkhead lights on my 25' sailboat. So I took one off today and
looked in it and it said it was rated for up to 220 volts. Does this mean I
can go out and buy cheap Target fixtures and install 12v bulbs in 'em and
they'll work? West Marine's fixtures cost about about 5 times more than
they're worth it seems to me. Thanks again!

On Mon, 20 Dec 2004 08:32:09 GMT, "Falky foo"
wrote:

Hey, thanks much for all the help recently. I want to replace the bare-bulb
interior bulkhead lights on my 25' sailboat. So I took one off today and
looked in it and it said it was rated for up to 220 volts. Does this mean I
can go out and buy cheap Target fixtures and install 12v bulbs in 'em and
they'll work? West Marine's fixtures cost about about 5 times more than
they're worth it seems to me. Thanks again!

If you can find a fixture that will accept the type of 12 volt
lightbulb you use, it will work fine.

The rating @ 220 volts means that the fixture will handle about 18
amps at 100 watts. So it has plenty of capacity.

I've never taken a marine fixture apart, but one reason for the
difference in price may be the way it's manufactured - I believe
marine units for interior spaces are sealed, or relatively sealed,
against moisture, vapor and such But I'm not sure about that.

In any case, I'd rather pay a little more for a fixture made and
designed for the application rather than not.

Later,

Tom

Falky foo wrote:
Hey, thanks much for all the help recently. I want to replace the bare-bulb
interior bulkhead lights on my 25' sailboat. So I took one off today and
looked in it and it said it was rated for up to 220 volts. Does this mean I
can go out and buy cheap Target fixtures and install 12v bulbs in 'em and
they'll work? West Marine's fixtures cost about about 5 times more than
they're worth it seems to me. Thanks again!




Yes it does mean that but like most things;-) be a little careful of
any related wiring/switches etc the 220 volt light may already have.

The volt rating just refers to the insulation ability of the
wiring/switches etc (volts=pressure) not the load carry ability of the
wiring (amps=flow/volume).

To get a reasonable amount of light out of 12 volts you'll need
probably 12-15 watt bulbs as a bare minimum which is 1-1.25 amps.

A normal 220 volt lamp with say a 60 watt bulb is only drawing about
0.25 amps.

So you can see that the very small but well insulated wiring etc within
the lamp may be over loaded & get hot if subjected to a sustained load
of 4 to 6 times the designed intention, even though it's only @ 12 volts.

Being aware of the issue you can choose a lamp which minimises the
problem or you can rewire it with heavier gauge wire if you like.

There are some 12 volt lights about 2" in diam used as spot lights or
feature lights in shops but also houses etc, they come with a
transformer for domestic mains use. They are popular on boats, plastic
(no corrosion) exceedingly cheap, very very bright (4 amps) & save you
handle it, have a long life tungsten globe. You can buy just the globe
it comes with the reflector as part of it & just mount it where ever.


K

If you can find a fixture that will accept the type of 12 volt
lightbulb you use, it will work fine.

it is not a 12 volt lightbulb you need, but rather a 12 volt ballast

For an under shelf, out of sight light, I used a cheap floro light from J. C.
Whitney at about 20% of the cost of a similar light output as the marine
stores. It has worked fine for many years now.

Hey, thanks much for all the help recently. I want to replace the bare-bulb
interior bulkhead lights on my 25' sailboat. So I took one off today and
looked in it and it said it was rated for up to 220 volts. Does this mean I
can go out and buy cheap Target fixtures and install 12v bulbs in 'em and
they'll work? West Marine's fixtures cost about about 5 times more than
they're worth it seems to me. Thanks again!

"Falky foo" wrote in message
. ..
Hey, thanks much for all the help recently. I want to replace the
bare-bulb
interior bulkhead lights on my 25' sailboat. So I took one off today and
looked in it and it said it was rated for up to 220 volts. Does this mean
I
can go out and buy cheap Target fixtures and install 12v bulbs in 'em and
they'll work? West Marine's fixtures cost about about 5 times more than
they're worth it seems to me. Thanks again!



As I read your post, you are saying that the existing FIXTURES are
rated for 220 volts. This does not necessarily mean that the wiring
leading to that fixture is rated for 220 volts.

Thank again guys!


"K. Smith" wrote in message
...
Falky foo wrote:
Hey, thanks much for all the help recently. I want to replace the
bare-bulb
interior bulkhead lights on my 25' sailboat. So I took one off today
and
looked in it and it said it was rated for up to 220 volts. Does this
mean I
can go out and buy cheap Target fixtures and install 12v bulbs in 'em
and
they'll work? West Marine's fixtures cost about about 5 times more than
they're worth it seems to me. Thanks again!




Yes it does mean that but like most things;-) be a little careful of
any related wiring/switches etc the 220 volt light may already have.

The volt rating just refers to the insulation ability of the
wiring/switches etc (volts=pressure) not the load carry ability of the
wiring (amps=flow/volume).

To get a reasonable amount of light out of 12 volts you'll need
probably 12-15 watt bulbs as a bare minimum which is 1-1.25 amps.

A normal 220 volt lamp with say a 60 watt bulb is only drawing about
0.25 amps.

So you can see that the very small but well insulated wiring etc within
the lamp may be over loaded & get hot if subjected to a sustained load
of 4 to 6 times the designed intention, even though it's only @ 12 volts.

Being aware of the issue you can choose a lamp which minimises the
problem or you can rewire it with heavier gauge wire if you like.

There are some 12 volt lights about 2" in diam used as spot lights or
feature lights in shops but also houses etc, they come with a
transformer for domestic mains use. They are popular on boats, plastic
(no corrosion) exceedingly cheap, very very bright (4 amps) & save you
handle it, have a long life tungsten globe. You can buy just the globe
it comes with the reflector as part of it & just mount it where ever.


K

The common residential light fixtures are designed for Solid wire. So
you should concider using a ferule to prevent any loose strands of
marine wire from causing a short. Also the manufacturer of a
residential product will not have concidered things like marine
corrosion, so you should.

On Mon, 20 Dec 2004 15:14:12 -0500, Gene Kearns
wrote:

On Mon, 20 Dec 2004 11:23:09 GMT, Short Wave Sportfishing
wrote:

On Mon, 20 Dec 2004 08:32:09 GMT, "Falky foo"
wrote:

Hey, thanks much for all the help recently. I want to replace the bare-bulb
interior bulkhead lights on my 25' sailboat. So I took one off today and
looked in it and it said it was rated for up to 220 volts. Does this mean I
can go out and buy cheap Target fixtures and install 12v bulbs in 'em and
they'll work? West Marine's fixtures cost about about 5 times more than
they're worth it seems to me. Thanks again!

If you can find a fixture that will accept the type of 12 volt
lightbulb you use, it will work fine.


I think not. Remember, the *fixture* is looking for 120V AC and is
going to see 12V DC.....

It is highly unlikely that the fixture will have the appropriate
starting mechanism(s)..

I assumed that this wasn't florescent but a straight filament bulb.

Any fixture can handle any voltage if it's a filament bulb.

Later,

Tom

Might look at RV fixtures also.
G
"Falky foo" wrote in message
. ..
Thank again guys!


"K. Smith" wrote in message
...
Falky foo wrote:
Hey, thanks much for all the help recently. I want to replace the
bare-bulb
interior bulkhead lights on my 25' sailboat. So I took one off today
and
looked in it and it said it was rated for up to 220 volts. Does this
mean I
can go out and buy cheap Target fixtures and install 12v bulbs in 'em
and
they'll work? West Marine's fixtures cost about about 5 times more
than
they're worth it seems to me. Thanks again!




Yes it does mean that but like most things;-) be a little careful of
any related wiring/switches etc the 220 volt light may already have.

The volt rating just refers to the insulation ability of the
wiring/switches etc (volts=pressure) not the load carry ability of the
wiring (amps=flow/volume).

To get a reasonable amount of light out of 12 volts you'll need
probably 12-15 watt bulbs as a bare minimum which is 1-1.25 amps.

A normal 220 volt lamp with say a 60 watt bulb is only drawing about
0.25 amps.

So you can see that the very small but well insulated wiring etc within
the lamp may be over loaded & get hot if subjected to a sustained load
of 4 to 6 times the designed intention, even though it's only @ 12
volts.

Being aware of the issue you can choose a lamp which minimises the
problem or you can rewire it with heavier gauge wire if you like.

There are some 12 volt lights about 2" in diam used as spot lights or
feature lights in shops but also houses etc, they come with a
transformer for domestic mains use. They are popular on boats, plastic
(no corrosion) exceedingly cheap, very very bright (4 amps) & save you
handle it, have a long life tungsten globe. You can buy just the globe
it comes with the reflector as part of it & just mount it where ever.


K

no actually it's straight incandescent I'm looking for. I understand that
12v fluorescent and 120v fluorescent would be two different beasts entirely.

I'm figuring that an incandescent fixture is really nothing more than a
fancy switch. Whereas a florescent has the ballast, etc.




"Gene Kearns" wrote in message
...
On Mon, 20 Dec 2004 20:32:21 GMT, Short Wave Sportfishing
wrote:



I assumed that this wasn't florescent but a straight filament bulb.

Any fixture can handle any voltage if it's a filament bulb.


True.... the "Target" thing made me assume that it was probably
fluorescent.... I could be wrong...

--



Grady-White Gulfstream, out of Southport, NC.

http://myworkshop.idleplay.net/
Homepage*
http://www.southharbourvillageinn.com/directions.asp Where
Southport,NC is located.
http://www.thebayguide.com/rec.boats
Rec.boats at Lee Yeaton's Bayguide

* If you find that you are denied access to my web page, Please respond
here with
your IP address and I will see if I can open up access. I have been forced
to
blackhole large geographic regions outside of North America due to
incessant
spoofing and hacking attacks on my web server. Thanks.

Falky foo wrote in message
.. .

no actually it's straight incandescent I'm looking for. I understand that
12v fluorescent and 120v fluorescent would be two different beasts
entirely.

I'm figuring that an incandescent fixture is really nothing more than a
fancy switch. Whereas a florescent has the ballast, etc.


The only thing you need to watch out for is this:

A fixture designed for a 120 volt bulb will need to handle 10 times the
current when using a 12 volt bulb, assuming the same wattage. A 100 watt,
120 volt bulb will draw just under an amp. A 12 volt, 100 watt bulb will
draw over 8 amps. The wiring within the fixture must be capable of handling
the higher current, regardless of the voltage rating.

Eisboch (trying to prevent fires)

On Tue, 21 Dec 2004 11:59:17 GMT, "Eisboch"
wrote:


Falky foo wrote in message
. ..

no actually it's straight incandescent I'm looking for. I understand that
12v fluorescent and 120v fluorescent would be two different beasts
entirely.

I'm figuring that an incandescent fixture is really nothing more than a
fancy switch. Whereas a florescent has the ballast, etc.


The only thing you need to watch out for is this:

A fixture designed for a 120 volt bulb will need to handle 10 times the
current when using a 12 volt bulb, assuming the same wattage. A 100 watt,
120 volt bulb will draw just under an amp. A 12 volt, 100 watt bulb will
draw over 8 amps. The wiring within the fixture must be capable of handling
the higher current, regardless of the voltage rating.

Good point - I wasn't thinking.

Later,

Tom

Thanks for the 'fo (that's short for 'info'). I'll keep em 10-20 watts.


"Eisboch" wrote in message
...

Falky foo wrote in message
.. .

no actually it's straight incandescent I'm looking for. I understand
that
12v fluorescent and 120v fluorescent would be two different beasts
entirely.

I'm figuring that an incandescent fixture is really nothing more than a
fancy switch. Whereas a florescent has the ballast, etc.


The only thing you need to watch out for is this:

A fixture designed for a 120 volt bulb will need to handle 10 times the
current when using a 12 volt bulb, assuming the same wattage. A 100 watt,
120 volt bulb will draw just under an amp. A 12 volt, 100 watt bulb will
draw over 8 amps. The wiring within the fixture must be capable of
handling
the higher current, regardless of the voltage rating.

Eisboch (trying to prevent fires)