Hi there. I am planning on building a fixture for outdoor use. The fixture will be lighting part of my back yard with low pressure sodium. I will be using an 18 watt bulb and a fulham ballast. This installation will be a dusk to dawn set up (photocell). I can think of four components, Ballast, photocell, bayonet, and the bulb. The fixture will be grounded and wired properly according to NEC (grounding of the ballast, proper live neutral wire hookup, accessability to all wires that are joined, etc). I am planning on mounting the bulb horizontally. This will be a residential install. Safety is my top priority.

The environment is as follows. Mild outdoor weather. Very wet in the winter with temperatures ranging from -5 to 10 c. The summers are dry and warm, but not hot (15 to 20 c but rarely over 35 c).
I have two thoughts on this: I can locate a fixture and remove the current lighting technology or build one. Locating a used fixture is probably the best bet, but I want to make sure that I can find something that is going to work well for wet weather. I have to keep water out of the fixture.

I am looking for comments from people who have done the same thing. Does the lamp hold up well to elements? Is the monochromatic color illumination less visible to insects? Thoughts...

A house in my area has an older version of the Philips Goldfinger without a diffuser. Has been like that for a couple of years, and was still lit this week. The SOX lamps are quite tough, I believe.

Any fixture preventing direct contact of water with the lamp or with electricity, and accumulation of water (and condensation) in the fixture is sufficient

Open fixtures are still working in many places for many decades now without any problems. Just make sure there is nothing directly below the fixture from which water can splash up and hit the lamp. The pros are that you dont have to seal anything, cons that it accumulate dust with time, can get damaged from a water splash

But open fixtures can be a problem for electronic ballast - it will tend to get condensation inside (from the harsh temperature difference) and fail if it is not protected from severe temperature changes

Closed fixtures are better at light output maintenance and protection, but only if they are completely sealed. Otherwise it will be even worse than open fixture - it will suck in cold air when switched off, and fill with dirt and possibly with water too



The electronic ballast have to be close to the lamp. Magneic ballast does not and can be up to several M / few tens Ft away as long as the ignitor is at the lamp

You can use sheet metal parts (gutter / window frame / pots / etc) to manufacture an open fixture, then install the ballast in a waterproof sealed box with small hole on the bottom to let water out

For closed fixture, use any incasndescent fixture of your choicwe and fit the components in it

If the ballast box can be put under the shed's roof (while still be fully adjacent to the fixture) it is advantage

Protect any plastic parts from direct or bright reflected sunligvht. If left exposed they will tend to fall apart from the UV after few years



I dont know what LPS color looks like but i'd imagine same as the deep orange that some HPS have before they fully warm up

Thank you. So that I understand, an electron ballast needs to be wired close. No long wire runs? Less than a meter of wire?

Really as short as possible. The one meter should be just OK...