Many years ago, there were some unusual bulbs that people used in various
situations when they wanted a very white light. This bulb was the choice
for people to achieve that lighting effect when replacing incandescent lamps, it
was the self ballasted mercury vapor. There are still some places where
people use these. The lamp is a mercury lamp that operates without the need
of a ballast. All other types of mercury and HID lamps need a ballast to
operate them and maintain the arc. That's not the case with this type, but
there are some misconceptions that need to be cleared up. Although it doesn't need the coating to produce light, many times
it is used with the coated version of the lamp. In the past, manufacturers
tried to make the color more warm by using a coating on the inside of the lamp
and that coating is usually referred to as deluxe white. Another thing to
consider, these really aren't a true HID light and it doesn't put out much more
lumens per watt than an ordinary incandescent. It's not a way to save
energy or to produce more light, if you need that, then you would want a whole
new fixture with metal halide lighting.
All the major manufacturers like Sylvania, produce self ballasted mercury vapor light
bulbs in all kinds of wattages and sizes. It has an excellent construction and has been a top
performer among the other brands. The lamps are interchangeable as far as
wattage goes because they don't need a ballast. A lamp of 100 watt can be swapped with a 250 watt and so on. They come is various
configurations such as mogul base or medium base and an egg shape bulb or as a
R40 flood light. In some cases, it's all that can be used.
Some people wonder about the color of these lamps. Is
there a color shift from different manufacturers? The answer
is a definite yes, and there can be a different color between manufacturers and various
lots. Self ballasted mercury bulbs are known for getting a slight greenish color
at the end of it's life, like other mercury lamps. The unfortunate thing is that they can seemingly
last forever in that state and people will leave them in place because it's lit.
But the truth is, it should be replaced when that happens. Be aware that color can shift over
time and the only way to get back to the original color is to replace the lamp.
It's sometimes a sign of end of lamp life. In most architectural specifications,
mercury bulbs are being replaced with metal halide, the HID lamp of choice for almost all
high light output applications.
With the advent of more efficient lamps, self ballasted mercury are
almost never specified.
The various manufacturers have different
names for their product, but we stock the most popular self ballasted lamps. We
have a large inventory of these lamps for nearly every type of
light fixture in the field. If you need help identifying a bulb, our customer service representatives can help you determine what you have.