Many decades ago, after the development of fluorescent lighting in general, lighting engineers realized that they would need fluorescent
bulbs to work outdoors or under cold temperature conditions. There were several issues
to overcome, but the most important were starting the lamp in cold temperatures
and maintaining a high light output as well. The ballast is critical in
this system and you can't have one without the other, HO lamps or ballasts. The development came into
what are called generally high output fluorescent ballasts. These have
the ability to start the lamp at a lower starting temperature than standard
ballasts and creating a higher lumen output too. The typical applications
are outdoor lighting, sign lighting and coolers and freezers which need a lot of
light maintained regardless of the cold temperature. The most common type
of these are still the T12/HO, but there are also T8 and T5 HO choices in
today's market. One of the ways that these are abbreviated is with the two
letters HO. If you ever see HO as part of the code number, you will know
that they are high output fluorescent light bulbs. You will find these in
almost any length as they have many different lighting applications so they can
be as little as 2 feet long and as much as 10 feet in some special cases.
As with all fluorescent bulbs, they rely on particular ballasts in the fixtures
for proper operation. The ballasts for the HO lamps are usually much larger than
the standard types, and put out a lot more heat. These ballasts are very
heavy too! Some of that is changing when it comes to electronic ballasts
as they have a size that is almost the same as the standard electronic ballast.
The old style HO ballasts are very heavy as they have large windings inside.
The ballast is important because it is specific for each type of lamp. You
can't change from one type of fluorescent to another without changing the
ballast in most cases. Most of the time the ballast and the lamp are
matched electrically and so it's good to make sure the ballast you have is the
right one for the lamp you choose. In the case of magnetic high output
fluorescent ballasts, you will find that many of these will operate various
lengths within a certain range. Such as the 8 foot and 6 foot lamps
sometimes use the same HO ballast. Almost every manufacturer makes high
output fluorescent ballasts, among them are Universal ballasts and many others.
There is always a choice when it comes to the voltage to operate the ballast.
Most of the time, you will find them in 120 or 277 volt, which are the most
common. Sometimes on a rare occasion you might see a 480 volt in a VHO
lamp system. That's a little different than the lamps we're talking about
here, but is similar and almost obsolete. It's important to get the
voltage right or else the ballast will not work or the high voltage can
instantly burn out the ballast.
Keep in mind that there are many ballasts for high output fluorescent light bulbs, we
describe some of the general characteristics here. We have a large inventory of
high output fluorescent ballasts for nearly every type of light fixture in the
field. It's never a problem to get what you need since Universal is our preferred brand of
this type of lighting. If
you need help identifying a ballast, our customer service
representatives can help you determine which one it is by the code number on the
label. We have extensive cross references which will tell us exactly what
you have, no problem!